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Talk:Anatomical Record 19 (1920)
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THE
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ANATOMICAL RECORD
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EDITORIAL BOARD Irving Hardestt Warren H. Lewis
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Tulane University Johns Hopkins University
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Clarence M. Jackson Charies F. W. McClure
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University of Minnesota Princeton University
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Thomas G. Lee William S. Miller
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University of Minnesota University of Wisconsin
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Frederic T. Lewis Florence R. Sarin
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Harvard University Johns Hopkins University
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George L. Streeter
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University of Michigan
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G. Carl Huber, Managing Editor
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1330 Hill Street, Ann Arbor. MlehlEan
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VOLU:\IE 19 JUNE— X0VE:\IBER, 1920
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PHILADELPHIA
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THE WISTAR INSTITUTE OF ANATOMY AND BIOLOGY
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CONTENTS
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NO. 1. JUNE
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John Sheltox Horsley, Jr. A description of a six-legged dog. .Si.\toen figures 1
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Howard B. Adelmann. An e.xtreme case of spina bifida with dorsal hernia in a calf.
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Two figures 29
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R. M. Strong. An inexpensive model of the principal spinal cord and brain stem
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tracts. Two figures 35
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Jacob Reighard. The storage and handling of wall charts. Four figures 39
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Roy L. Moodie. The nature of the primitive Haversian system. One plate (three
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figures) 47
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Hubert Sheppard. Hermaphroditism in man. Seven figures. 55
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Book Reviews — Hal Downey. Le Emopatie 67
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NO. 2. JULY
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J. A. Fires de Lima. Anatomy of a fetus of a cyclopean goat. Six figures 73
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Otto F. Kamp.meier. The changes o' the .systemic venous plan during development
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and the relation of the lymph hearts to them in Anura. Xine figures S3
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H. E. Jordan. Studies on striped muscle structure. VII. The development of the
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sarcostyle of the wing muscle of the wasp, with a consideration of the phj'sico chemieal basis of contraction. Thirteen figures (two plates) 97
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Kaethe W. Dewey. A contribution to the study of the lymphatic system of the eye.
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Throe figures 125
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Ralph A. Korde.vat. Contamination of cadavers by Saccharomyces cerevisiae. Two
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figures 145
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NO. 3. AUGUST
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E. D. Conodon. Simultaneous occurrence of very small sphenoid and frontal sinuses.
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Two figures 153
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E. D. CoNGDON. .\nomalous fibrous cords in the hand and the phylogeny of the flexor
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digitorum sublimis tendon. Two figures 159
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E. D. CoNGDON. .\c(n,iired skeletal deformities in a young fowl. Six figures 165
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Franci.s Marsh Baldwin. Notes on the branches of the aorta (arcus aortae) and the
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subclavian artery of the rabbit. Eleven figures (one plate) 173
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Jo.SEPH M. Thuringer. a suggestion for improvement in projection and drawing
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apparatuses. One figure 1S5
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James Cr.\wfobd Watt. Symmetrical bilateral dystopia of the kidneys in a human
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subject, with outward rotation of the hilus, multiple arteries and veins, and a
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persistent posterior cardinal vein. Two figures ISO
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iii
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iv rOXTENTS
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NO. 4. SEPTEMBER
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HiiKN J. Cakkv. Slmlii'!' in Iho ilyniunios nf liistogciiosis. (irowth motive force as a liymunic stimulus to the genesis of inii»iMil:ir anil skeletal tissues. Twenty figures. . 199
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Our AH V. Batson. Dc-cloct rifirnt ion of pnraflin ribbon by means of high-frequency ranrnt 237
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IICN'KT Baton. A case of ossified costoeoracoiti membrane fused with the clavicle. One
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ligu re 239
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IIiMn Uavon. Rarinl and sexual differences in the appendix vermiformis 241
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NO. .-). OCTOBER
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\UL li. IIartman. Studies in the development of the opossum Didelpbys virginiaua L. V. The phenomena of parturition 251
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I ('. M v\v. .Vms.sory pancreas in the dog. Five figures 263
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II I. WiiMvN I iliwMTvalions in connection with the early development of the human
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Two plates (nine fiitiires) 269
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WD Thai V JaiTvso.n PfT.VAM. Xote on the tinatomy of the areae
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ri«-. ( »!»• plate (four fiKuri'S) 281
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.\i PtTRrvKKViTi'ii. Standardized raicrophotography 2S9
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NO. (i. NOVEMBER
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Fkvxk Hi. mi* Ha.vsox. The history of the earliest stages in the human clavicle. Four
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platfs (thirteen figures) 309
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Krvsk Blair IIansox. The problem of the coracoid. Two plates (seven figures) 327
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lloui.ii B I.Mivni:. The weights of the viscera of the turtle 347
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Otto I The collateral circulation in a case of complete closure of the
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ni" ..■•rior vena cava. Two figures 361
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E. D. C'oNi.iMi.v. .\ supernumerary paranasal sinus. One figure 367
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f'l.AKEXcr. L. TrRXER. .\ wax model of a presomite human embryo. Eighty-one
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figures 373
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>
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THE ANATOMICAL RECORD, VOL. 19, NO. 1 JUNE, 1920
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V
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Hesumen por el autor, John Sholton Horsley, Jr., rniversidad de Virginia.
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Dcscripci6n de un perro con seis patas.
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El preseiito trabajo es una descripci6n detallada dc la anatomfa externa e interna de una jM^rra j6ven que poseia im par adicional de pata.s posteriore.s bastante nomiales y colocadas sim^tricaniente. Este ni<')nstruo jjresentaba un par de pelvis casi norniales fusionadaf; entre si, una cloaca en el lado derecho, ano y vagina .separados en el lado izquierdo, dos vejigas urinarias, un .'«ol<> rin6n. un ur(t('r iinpar en conexi6n con la vejiga izquierda, un solo intestino deigado. dos colon, dos ciego.s con sus corres{)ondientcs apendices, giandulas suprarrenales pares y dos literos provistos cada uno de un tubo uterino y un ovario. La.s tibias de Ia.s patas supernumerarias estaban fusionadas.
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Tr»n*Ution l>y Jc*^ K Nunidrs Conirll l'nivrr»ily Mrth'-aK'ollrgr. N. V.
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AUTHOR B ABSTRACT OP TH!9 PAPER ISSUED BY THE BIBLIOGRAPHIC SERVICE, MAT 10
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A DESCRIPTION OF A SIX-LEGGED DOG
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JOHN SHELTON HORSLEY, JR. Department of Anatomy, University of Virginia
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SIXTEEN FIQUBES
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On January 11, 1919, Mr. John R. Raines, a farmer living near the University, brought to Prof. H. E. Jordan's laboratory a dead female dog with an extra pair of hind legs. The thoracic and abdomnial cavities were opened and the dog at once placed in a 10 per cent solution of formalin. This specimen was subsequently turned over to me for study and description. The work was done in the Laboratorj^ of Histologj' and Embrj'ology under the supervision of Professor Jordan, to whom I am greatly indebted for the privilege.
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From Mr. Raines were secured the following data: The dog was born October 7, 1918; died from exposure to cold the night of January 9, 1919. Her father was a shepherd, her mother a bull-terrier; both parents were apparently normal. The litter included in addition to this abnormal individual one normal brother and three normal sisters. The six-legged puppy appeared in life otherwise normal and healthy, and was apparently but little inconvenienced in walking and running by the extra pair of legs, which she carried slightly raised above the ground. The unpaired tail was apparently under perfect control.
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EXTERNAL APPEARANCE
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As regards the shape and general appearance of the head this dog more nearly resembled a fox-terrier, and she was about the size of this type of dog (fig. 1). With the exception of the nipples, she appeared normal cephalad of the umbilicus. "\Mth the exception of the tail and anus, she was double caudad of this point.
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2 JOHN SIIKI.TON UOUSLEV, JU.
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Closer oxaiuiimtion rovoalo<l the following details: The log, vagina, aims, and tail of iho loft sido woro displacod about 1 cm. lalorad of ihoir norinal rolativo ])()sition with rospoct to the vertobrtl column. The sagittal plane of the proximal portion of the tail made an angle of 'Jo degrees with that of the verteliral colunui. The right leg was tlispiaced slightly forward and dextrad of its nonnal position. It was .^lightly smaller than the left leg and presenteil a rather undeveloped appearance, especially in the size of the thigh nuisoles. Between these two legs hung the extra pair of legs. The pair was inclined a little to the right of the medial line and it was enveloped in a common integument Wi far (list ally as the ankles. The members of the pair were of apj)roximately efiual size and represented genuine hind legs. Barring a ver>' slight ventral bend at the level of the knees, the pair was extendetl in a straight line and it was placed in such a way that the pads of the feet faced toward the groimd when the dog was standing. The pair measured IS.o cm. from the heads of the femurs to the tips of the toes. These extra legs were only slightly more slender and shorter than the other two hind legs. Palpation nidicate<l a fu.sion of the tibiae, a conclusion confirme<l by roentgenograms (figs. 2 and 3) and subsequent dissection. The extra legs articulated with the medial surfaces of the opposite halves of the paired jielves slightly forward, and to the right, of the root of the tail. There was no second tail or anus, but there was a second set of external genitalia 2 cm. below and to the right of the articulations of the extra pair of legs. The vertebral column in the region of the sacrum seemed abnormally wide on the right side and presented abnoniial landmarks, description of which will be reverted to subsequently. Just below the right side of the double knee there was a roughened scarlike area, whose significance will also be indicated below.
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SIX-LEGGED DOG 6
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INTERNAL ANATOMY Osteology
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The vertebral column contained the usual number of vertebrae, namely seven cervical, thirteen thoracic, seven linnbar, three sacral, and nineteen caudal (fig. 2). It remained single throughout and was normal as far as the seventh lumbar vertebra, which latter was normal on the left side, but presented a large wellrounded mammillary process that was twisted dorsally and slightly caudally extending on the same level with that of the corresponding ^•ertebral spine. The sacrum was very slightly bent to the left. On the right the articular surface of the first sacral vertebra was turned dorsally, and accordingly produced a slight elevation. There was also on the right side an oblong, irregular plate of bone that measured 10 mm. in length, 7 mm. in thickness, and 6 mm. in the vertical plane (fig. 4, M). It was fused with the first and second sacral vertebrae, and represented a second deformed sacrum. On the left side the sacropelvic articulation was normal with the exception of a small piece of bone, 8 mm. in length, which jutted out caudally from the left ilium at the level of the sacrum and was fused with the second and third sacral vertebrae. There was a gentle curve to the left, formed b}' the first three caudal vertebrae, the first of which articulated on its right side with the base of the fused ilia. The remaining caudal vertebrae were normal.
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Two pelves were present (fig. 3). At first observation there seemed to be a smaller medial pelvis fused dorsally to a larger and practically normal ventral pelvis; but after closer examination of all of the related structures the conclusion was reached that the condition was one of lateral fusion between a right and left pelvis. The course of the unpaired sciatic nerve is the only obstacle to the latter interpretation. The right and left lateral ilia were of normal size (figs. 4 and 5). The left iUum articulated with the sacrum of the left side in the usual manner, with the exception of the intervention of a small spur of bone extending caudally from it. This has alreadj- been described. The crest of the right ilium was displaced cephahcly 1 cm. and dorsally
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4 JOHN 8HELTON HORSLEY, JR.
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3 mm. .\ sninll triftiiRular piece of bone, 1.5 cm. in length, articulutcMl with the riplit deformed saenmi bj' a number of strong hgamciits forming an amphiarthrosis (fig. 4 A). The crcst.s of these hiteral iUa were about G nun. further apart than they shouhl have been if the right had its normal position and the two considered part of one pelvis.
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The right anil left nie<lial ilia were fused to form one bone which presented a dorsally protruding crest (fig. 4). This fused medial ilium was approximately a third the size of the nonnal lateral ilia. The vestigial right sacrum was fused with the base of the metlial fused ilium. These two structures were continuous on the ventral surface, but dorsally there was a de]5ression partially separating them. On the left the base of the fused ilium was joined to liie third sacral vertebra by a sjnichondrosis, and with the first (proximal) caudal vertebra by a syndesmosis. This fusion of the ilia had brought the two medial acetabula so close together on the dorsal surface that they nearly touched each other (fig. 5). The long axis of this medially fused ilial portion of the compound pelvis made a 15 degree angle with the midline on the right side. If considerefl as a dorsally interpolated {)elvis, it would be al)out half the size of the larger pelvis.
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The two metlial ischia formed a basin, which was open dorsocaudally and close<l ventrocephalicly, presenting on each side the relatively high crests of the two medial tubera ischii. The basin measured 3.7 cm. from crest to crest (fig. 5). In this basin lay the necks and proximal fourths of the femurs of the extra two legs, along with that portion of the heads that did not enter directly into the hii)-joints (fig. 4). The two obturator foramma opened ventrocephalicly through each side. They were completely closed by thin ligamentous bands and were of about half the normal size. Caudal to the fusion of the medial ilia, and aI.so to the acetabula, there was a ver>' firm union between the right and left pelves along the whole length of the pubo-ischial 8^^nphysis of each (fig. 't). This lino of fusion would call for the .'iame description whether the fuseil i)elves were interpreted as right and left or dorsal and ventral components.
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SIX-LEGGED DOG 5
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The heads of the femurs of the extra two legs were about 1 mm. apart and articulated with the two medial acetabula, each forming an enarthrosis. The articulations were alike on both sides, and normal to the extent that they formed ball-and-socket jomts, with synovial bursae, ligamentous capsules, etc. There was a slight twisting, however, produced by their abnormal positions. All of the structures that entered into these articulations were of approxunately half the size of the corresponding structures of the normal right and left lateral hip-joint. The movements of these articulations were Umited practically to a dorso\-entral action due to the fusion of the tibiae of the two extra legs (fig. 3).
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The right and left lateral ischia were of normal size, but were slightly twisted laterally, the right more so than the left. The crest of the right lateral tuber ischii was 1 cm. laterad of that of the right medial tuber ischii at the widest point (fig. 4). The right colon, vagina, and urethra united within the basm formed by these ischia into a cloaca (fig. 12). The opening of this basin was the pelvic mouth of the right pelvis. The corresponding crests of the left side were 2 cm. apart at their widest points and formed a somewhat less constricted basin for the left vagina. The aperture of this basin was the peh-ic mouth of the left pelvis (fig. 5).
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The bones of the right and left lateral legs were normal. Those of the extra two medial legs were verj^ slightly shorter and slightly more slender than the lateral ones, as may be seen in figure 3. The tibiae of the supernumerary legs were fused medially along their whole extent. The fibulae appeared slightly larger than normal, the left fibula being more intimately fused with its tibia (fig. 3). No other marked abnormalities occurred in the bony structures. The double knee-joint was practically immobile except for a very sUght action in the caudocephaUc direction.
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Myology
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The muscles of the left lateral leg, thigh, and hip regions were nonnal; those of the right thigh also appeared normal except for a somewhat smaller size.
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(I JOHN SIIKLTON HOIlSI,EV, JR.
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Ill the hip repion of the two extra legs there occurred only a vt'Pk- few small imKscles that i)asso<l down to the thiph. These muscles were inserted aloiin tlie i)r(>xinial portions of the two femurs and seemed to re|>resent only remnants. There was a layer of superficial fascia over the whole of this nuiscle mass. Some atri>i)hic vestigial muscles covered the popliteal fossae extending up over the distal two-thirds of the two femurs and down well over the ventral portion of the knee-joint. They were better devclojied on the loft member than on the right. The .space between the two femurs was oc('Ui)icd by an arterj', a vein, a large nerve, and an abundance of loose connective tissue. The two legs of the extra pair were bound together by a sujierficial layer of fascia and the integument. There were two verj- distinct teiulons of .\chilles: the one of the left leg was more pronounced, and it was stretched so tight as to permit only very little movement of the left foot. The right foot was more free to move. The Hexor digitorum brevis tendons were very distinct on the feet, but none of the muscles could be found. No muscles occurred beyond the extreme proximal ends of the fus(Hl tibiae: there was an enveloping layer of superficial fascia along their entire length.
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The ligamentum nuchae was the only abnormal structure observe<l cephalad of the diaphragm. This was a very thick, round ligament rather than, as usual, a tliin ligamentous raph^.
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Splanchnology
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The stomach, small intestines, liver, gall-bladder, spleen, and pancreas were unpaired and apparently normal.
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The large intestines were double; one colon was very nmch distende<l and lay ventrad and to the right of a smaller colon (figs. G, 7, and S). The former had verj- short ascending and transverse portions, but a long descending jiortion which was constricted in the middle. This constriction j)r(xluced two large .nacculations, the caudal being the more distended. The wall of this portion was rigid and brittle, ai)parently lacking muscle con.stituents. This larger colon pa.s.sed through the right pelvic
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SIX-LEGGED DOG 7
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mouth and opened into the vagina of the right side, thus contributing to the formation of a cloaca. The smaller colon of the left side had neither teniae nor sacculations; and there were practically no corresponding ascending or transverse portions. It joined a normal rectum which ended in a normal anus; it was on the whole more nearly normal than the right colon. Feces were found in both colons, and there were no adhesions or constrictions that could hinder either from functioning.
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The iliocolic portion of the small intestine was slightly enlarged, and at this point of enlargement the two colons anastomosed with each other and with the small intestine (fig. 6). Each colon had a caecum with an appendix. The right caecum was the larger and, excepting its increased size and its associated appendix, it seemed normal. This appendix was a constricted apical portion of about 1.5 cm. in length (fig. 6). The left caecum was very short, being about 1 cm. long. Its appendix had a smaller diameter than that of the right and was about three times as long (fig. 7). It was sharply folded at four distinct points into a compact structure.
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The single ileocolic vah-e was relatively large and covered both colic orifices, but was thickened in that portion overling the right orifice (fig. 8). Its opening was directed somewhat laterall}^ and gave vent nearly directly into the left colon. At a point immediately distal to the valve the lumens of the two colons united. On account of the thickening of one side of the valve, the connection between the lumens of the right colon and the small intestine was thrown to the left, somewhat toward the smaller colon. The caecocolic orifices of both colons were apparently normal (fig. 8). It may be of interest to note that there were ten persimmon seeds and a few whole grains of corn in the right colon. The great enlargement of the right colon may find its explanation in a gradual distention by fecal contents which could be only slowlj- voided due to lack of peristalsis following the paucity or lack of smooth muscle.
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On the right side the larger colon, the urethra, and the vagina had a common exit chamber, forming a cloaca (fig. 12). The right rectum formed the largest part of this chamber, and on
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8 JOHN SlIELTON HORSLEY, JR.
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this arroimt the orifires of the vagina and the urethra seemed to empty into it at a point about 3 cm. cephahul of the common external opening, the vagina on the medial and the urethra on the lateral sides, re.><pectively.
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The external genitalia of that side were slightly smaller than those of the l»ft. Itut had a generally normal appearance.
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The urogcnilal system
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The single kidney was situated on the left side. No trace of even a vestigial kidney could he found on the oi)posite side. 'I'his lone kidney, locatetl at the usual level, was considerably larger and more spheroidal than nonual (fig. 9). It received a large renal vein from the left side of the inferior vena cava; and slightly dorsad and caudad of this point it received a renal artery from the alidominal aorta. Midway between the latter and the pelvis of the kidney the renal arterj' divided into two, one entering dorsally and the other, after curving around the renal vein, entering ventrally and cephalidy to it. Before entering the pelvis the renal vein gave off a branch that coursed laterally over the ventrocaudal portion of the kidney to the left ovary and oviduct. .\. single large ureter passed caudally to empty into tlie left urinary ijladder in a normal way (fig. 10). The minute anatomy of this kidney was perfectly nonnal. Cephalad of the kidney, and in their proper positions, occurred two adrenals (fig. l»).
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Of the two urinary bladders the left was apparently normal, except that it wa.s slightly displaced to the left. The displacement was due chiefly to the presence of the greatlj' distended right colon. This bladder was comjjletely collapsed. Its urethra was normal, emptj'ing by means of the left vagina (fig. 10). The right urinary bladder was rigid and distended. It was comiKKSctl of brittle tissue a|)parently like that of the larger colon. It was obviou.sly smaller than the left bladder when the latter harl l)ecome distended. At its cephalic end there was a narrow circular area (.'i mm. in <liameter) of ver>' delicate tissue simulating a membrane, which yielded on the slightest pressure (fig.
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SIX-LEGGED DOG 9
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11). There was no vestige of a ureter in connection with this bladder. Its urethra had about twice the normal diameter, and was composed of the same kind of brittle tissue as the bladder. A medial longitudinal section of the bladder revealed a lining of elastic tissue that was hard to peel off and that had the macroscopic appearance and general consistency of a thin plate of cartilage. Irregular partitions extended from the walls fonning two large pockets at the eephahc and caudal ends of the bladder, respectively (fig. 11). Between these and in the central portion there were about ten smaller pockets. Along the entire ventral wall there was a space between this cartilage-like lining and the wall of the bladder which was continuous with the hunen of the urethra (fig. 11). The urethra had a very thick wall and emptied into the cloaca (fig. 12).
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The genital organs
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Two ovaries, each with its respective uterine tube (unpaired cornu uteri) leading to a respective uterus (corpus uteri), were situated in their normal positions. The ovary of the left side was flattened and oval in outline; that of the right side was flattened, elongated, and ahnost crescent-shaped, with a deep longitudinal groove extending over its lateroventral surface. The two uterine tubes extended caudomedially to their corresponding uteri (figs. 12 and 13). The right tube was the shorter and slightly the thicker of the two. The right uterus was about twice as long and thick as the left. The latter presented no peculiarities in its continuation into the vagina of the left side. The right vaguia was relatively short; it was continued mto the common chamber which formed the cloaca. Both uteri were abnormal to the extent that the}^ were unicornuate.
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P'our rows of asymmetrically distributed nipples, twelve in number, were present (fig. 14).
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10 JOHN SHELTON HOKSLEY, JR.
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.1 ngiology
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The hIcMMl su|)i)ly of the kidiioy has horn tlescriho<l ahovo. No triu'os of any hloocl-vessols that niiKht have corresponded to the right renal arterj- and vein coultl lie found.
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The alxlotninal aorta and the inferior vena cava remained single throughout their entire course, but they gave off extra branches which supjilied the suijcrnunierar}- structures. The distribution of these two chief vessels and their principal branches is shown in figme 15. The abdominal aorta gave off a right eommon iliac arterj- a short distance cophalad of its usual place of branching. The left conmion iliac was larger than the right and seemed to represent a direct continuation of the abdominal aorta. Its course was in direct line with that of the aorta to a point about 1 cm. caudad of the i)oint of branching of the right conmion iliac. Here there was a gentle curve to the left, the main portion being continued as the left external iliac which |)rocee<le<l down the left lateral leg as the femoral artery. Slightly caudal to the beginning of this curve on the left common iliac just nientioned, and on the outside of it, a large branch came off which supplied the two extra legs, ^'ery close to the origin of this larger i)rancli there was a small branch which went to the left urinar>' bladtler; while just caudal to this a larger one came off and divided into two, the medial representing the caudal (middle sacral) and going to the tail, the lateral going to the structures in the left jielvic cavity and probably representing the left internal iliac artery.
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One principal artery and one principal \oin supplied thetwo extra legs. The i)lan of the arterial supjily is represented in figure 1(>; that of the venous sujiply is practically indentical. The vessels continued their course caudally between the two femurs, giving off two small branches, one on each side, just distal to the heads of the femurs, to supply the scanty muscles and fascia of that region. No other branches were discernible cephalad of a level about 2 cm. proximal to the knee-joint. At this point, however, both the artery and the vein divided into one meilial and two lateral branches, the two lateral branches of
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SIX-LEGGED DOG 11
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each vessel passing distally to the lateral sides of the fused tibiae and finally coming around on the dorsal side to f onn an anastomosing arch over the distal portion of the tibiae in the region of the ankle. From this arch sprang two main arteries and veins which passed on to supply the feet, the right set to the right foot and the left set to the left foot. Two medial smaller branches arose from the arch and supplied the structures in the immediate vicinity. The medial branch (fig. 16 M) of the principal vessels mentioned above represented a terminal branch. The medial artery and vein passed distally along the ventral line of fusion of the two tibiae where they became resolved into branches that supplied the structures of the ventral portion of the fused legs. The lateral branches supplied the structures of the lateral and dorsal surfaces. The \'enous system of the supernumerary legs paralleled the arterial system throughout its entire course.
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Numerous lymph nodes were found scattered throughout the abdomen. Just cephalad of the kidney occurred the two largest nodes. The smaller nodes were relatively more abundant along the inferior vena cava and the abdominal aorta. Those of the paired pelvic cavities were rather large and numerous. A large bean-shaped hanph node, about 1 cm. in length, was situated at the level of the stifle-joint on the ventral side. This probably represented a composite popliteal node and was apparently the only lymph node of the two extra legs.
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Neurology
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A large nerve accompanied the principal artery and vein of the two extra legs. This nerve presented an oval cystic enlargement, macroscopically suggestive of a ganglion, at the point where it entered the double leg, just distal to the heads of the two femurs. The nerve passed dorsal to the blood-vessels, accompanying them as far as they went, and then accompanying the terminal or medial branch down over the midline of the double stifle-joint. As the nerve passed the latter point it presented a gradual cone-shaped enlargement and, tiu'ning laterally and dorsall}^ around the medial condyle of the head of the
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12 JOIIX SHELTON HORSLEY, JR.
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rijclit til)ia, rii(lo<I abruptly in the skin (fig. Ki). On the external .surface of the skin this terniination presented a roughened scarlike appearance, the size of which was approximately that of the diameter of the nerve. Three smaller scar-like patches oceurred below, and slightly Tuedial to the principal one. No nerve fibers could be traced within the skin. The whole appearance of this nerve tennination seems exactly what might have been expected if the nerve had penetrated the skin and its external part had subsequently sloughed ofT, thus leaving a scar with the nerve firmly attached. The proximal part of this nerve was attached to the right wall of the cavity through which it coursed to the extra legs in company with the two main bloodvessels. This attachment was made by strands of tissue chiefly to the middle portion of the small opening. The portion of the nerve from the cyst forward consisted of a hollow, circular strand of tissue that tapered down almost to nothing. There remained no connection with the spinal cord. This nerve probably represented fused right and left medial sciatic nerv^es.
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CONCLUSIONS
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Viewing the double portion of this dog, it is seen that the left comjjonent is more fully tievel<)])ed and that it is nearly in nonnal jiosition. while the right component is entirely at the right of the median plane. The blood- vascular, the tligestive, and the urogenital s\stems, excepting the kidney, and the fusions and articulations of the pelvic limbs, all consistently support an interpretation of this monster in terms of a side-to-side pelvic fusion of twin primordia, with complete resorption of the prediaphragmatic portions. .V variant of this interj)retation might l)e based upon the supposition that an original unpaired embryonic disc suffered a caudal splitting to the point including the primordia of the pelves. It is not po.ssible with the available data to decide finally between the suggested alternatives of iusi(»n and splitting. However, the mixed character of the alxlominal vi.^cera (e.g., single kidney, double colon) .seems to favor the interpretation of fusion rather than of splitting. The
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SIX-LEGGED DOG 13
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one chief objection to the interpretation of lateral, as opposed to dorsoventral, fusion is the presence of the unpaired sciatic nerve of the extra two legs. It the interpretation of lateral fusion is accepted, then the compound sciatic nerve seems to be greatly displaced. The sciatic nerve normally passes through the pelvic mouth and then courses laterally over the acetabulum on down the leg. The sciatic nerve of the right and left lateral legs followed this normal course. The fused sciatic nerves of the supernumerary limbs, however, entered the pair by a single root, having passed thither between the two medial acetabula, and not, as normally, through their respective pelvic mouths. The apparently ectopic position of the fused sciatic nerv^es can be explained on the very probable supposition that the primordia of the originally paired medial sciatic nerves fused before the medial components of the pelves had developed beyond their blastemal stage. This explanation becomes the more plausible when it is recalled that the fused sciatic nerves had suffered degeneration at their proxhnal ends, due in all probability to pressure here following the further development and subsequent fusion of the two medial components of the right and left pelves.
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This dog belongs in the categorj' of duplicate monsters designated dipygus dibrachius tetrapus, and corresponds in general to the six-legged rat recently described by Conrow' and more closely to certain human monsters described under this designation by Broman.^
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LITERATURE CITED
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1 CoNuow, Sara B. 1917 A six-legged rat. Anat. Rec, vol. 12, p. 365.
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2 Broman, Ivar 1911 Normale und abnonne Entwicklung des Menschen.
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Bergmann, Wiesbaden, S. 190.
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a
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n
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X
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<
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a as b o C
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k.
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O
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z
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o
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p a
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H
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a
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XI
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j: c
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s
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Urn
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o o
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e! ■T3
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S
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o
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14
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^.
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o o
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Q
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P H O O
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15
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THE ANATOMICAL RECOllD, VOL. 10, NO. 1
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PLATE 2
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DESrRIPTIOX OF FICtJRES
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2 anil :{ U(irntgt'nogr;imby Dr. II. V. Ili|ip.
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ir>
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SIX-LEGGKD DOG
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JOHN SHELTON H0R6LEY, JR.
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PLATE 2
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17
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I'l.ATK :i
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DESCniPTlON OF FIGUKES
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4 Drnwinn of the (limbic bony struct iirps in the pelvic region viewed from the rinht side. A, left medial femur; li. ri(thl mediul femur; C, leftmedial tuberischii; D. riRht medial tuber isehii; E, right lateral tuber i?chii; F. right lateral femur; G, left lateral femur: //, right lateral ilium; /. left lateral ilium; J, fused medial ilin; A', fifth lumbar vertebra; L. caudal vertebrae; ^f , right deformed sacrum; .V, .•mall piec-e of bone articulating with right deformetl sacrum and right lateral ilium (possibly remnant of a second vertebral column*. Four-fifths life size. Drawn by Helen Lorraine.
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5 Drawing of thedouble bony structures in the pelvic region from a caudoventral aspect. .1. left medial femur; li. right medial femur; C, mouth of right pelvis; D, central point of the fusion between the right and left pelves, which extends along the pubo-i.schial .synij>hysis of each; E, left lateral obturator foramen; F, right lateral femur;fi, left lateral fenmr;//. sixth lumbar vertebra. Four-fifths life size. Drawn by Helen Lorraine.
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18
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SIX-I.EGGKD DOG
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JOHN 8HELTON HonsLEY, JR.
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PLATE 3
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lu
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I'LATK I
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DESCRIPTION OF FIliCHES
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6 Dniwinis of the iiiiastomosis of the siiiiill intcsfiiie witli the ri(];lit and left colons from a riRlit ventral aspect. The right eaeeiini with its associated appendix is also shown. The portion of the right eolon here shown rei)resents only one of the two sacculations that were i)re.sent. The second was approximately the same size. Four-fifths life size. Drawn by Helen Lorraine.
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7 Drawing of the anastomosis of the small intestine with the right and left colons from a left ventral aspect. The left caecum with its associated appendix is also shown. Four-fifths life size. Drawn hv lli'leii Lir.aine.
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20
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SIX-LKGGED DOG
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JOHN 8HELT0N HORSLET, JR.
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PLATE 4
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."Rt.cisecuTn
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5TnnaU\TilestvTi(?
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21
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I'LATK .)
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DESCRll'TION OK KKJURES
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8 Drawiiifc of tlio ileocolic valve from the riulit side. The ileum and right colon are .slit o|)en lonRitiulinally. Fcnir-fiftlis life size. Drawn by Melon Lorraine.
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9 DruuinK of ventral view of kidney with its hlood-siipply. sliowinR also the two adrenals. A', .single kidney of left side; /. anil L' . left and right adrenals; V, Hingle ureter leading to left urinary bladder; .1. abdominal aorta; V, inferior vena cava; R and IV, renal vein and artery; P. phrcnico-abdominal vein. Branch of renal vein to left ovarj' and uterine tube not shown in this drawing. Fourfifths life size.
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10 Drawing of left urinary bladder partially distended. The bladder is in a position to show^ the ureter emptying on the dorsal surface. Four-fifths life size.
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•a
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SIX-LEGGED DOG
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JOHN SHKLTON HOHSLKY, J».
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PLATE 5
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iLeo cestui
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caecLL-m
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caetairn.
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•Ur.te
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liritkrk
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23
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PLATE 6
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DKSCHIITION OF FIGURES
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11 Drawing of the interior of the ri({ht urinary Madder from a dorsal aspect. It is slit open dorsally in the longitudinal plane. Four-fifths life size. Drawn by Helen Lorraine.
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\2 Drawing of the cloaca and genital organs of the right side. Cloaca is slit open. O, right ovary; Ut, right uterine tube (uni)aired horn of right uterus) ; f, biHly of right uterus; i'r, urethra from right bladder; E and E', orifices of uterus and urethra into common exit chamber forming the cloaca; C, right colon. Four-fifths life size.
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13 Drawing of the genital organs of the left side. Vulva, vagina, and uterus (in parti arc slit open. 0, left ovary; Ul, left uterine tube; U, left uterus; E, external uterine orifice; //, hymen; E', external urethral orifice; V, vulva; .V, central projection of fold of mucous membrane which conceals the clitoris; F, fossa clitoridis; L, labia vulvae. Four-fifths life size.
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24
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SIX-LEGGED DOG
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JOHN SHELTON HOHSLEY. itt.
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I'LATIO 6
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,cvst wall
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'j-Te*
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nOTniai TTvuCOv
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u
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E'
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12
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25
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I'l.ATi; 7
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DESCRIITION- OK KKiUBES
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!• l)i:iKr:iiii of the :>rr:ingoiiicnt of the nipples. Each small blaek dm represfiiM a nipple. One-Kfteenth life size. ^l^iaSW
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l*> Diagrammatir drawing of the distal portion of the abdominal aorta and its branches .scon from a ventral view. .1, abdominal aorta; li.C.I., right common iliac; R.E.I. . right external iliac; li.F., right femoral to right lateral leg; L.E.I., left external iliac; L.F., left femoral to left lateral leg; D.L., artery to extra pair of legs; (', caudal artery to the tail; n and a', arteries to neighboring lymph nodes and other structures; b, artery to dorsal abdominal wall; c, arterj' to right colon; e and <•', arteries to structures in the right and middle portions of the pelvic cavity;/, artery to structures in the right i)orti(ui of the pelvic cavity (probably right internal iliac); (/, artery to left urinary bladder; h, arten,' to left ventral abdominal wall (probably left deep epigastric); i, artery to structures of left pelvic cavity. By pelvic cavity above is meant that portion enclosed between the lateral components of both the right and left i)elves. Veins accompanied the arteries.
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16 Diagram of the arteries and nerve of the extra pair uf legs as seen from a ventral view. The ner\-e ran immediately behind the main artery, but in the diagram it is shoved to the right. A, point of emergence of arterj- between the hea<ls of the two femurs; (', cystic enlargement on the unpaired sciatic nerve; W.the curve of the sciatic nerve around the medial condyle of the right medial tibia; E. tennination of the .sciatic nerve in the skin; I), point about 2 cm. above proximal end of fusion of two medial tibiae;/^, lateral branch which passed arounil the left medial leg (also level at which the sciatic nerve i)assed behind the stifle-joint I ; li, lati-ral branch which curved around the right medial leg; .1/, medial branch which ran along dorsal line of fusion of the two medial tibiae; .\r, anastomosing arch on the dorsal s\irface of the fused medial tibiae in the region of the ankles, formed by the two lateral branches; F and F', branches to right and left feet; m. small branches to the skin, fa.scia and scanty muscles; /. terminal branches of the medial branch supplying neighboring skin, fa.scia, and "-nnty muscles. Veins accompanied the arteries.
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26
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SIX-LEGGED DOG
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JOHN SHELTON HORSLET, JR
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PI-ATE 7
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27
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Rosuiiifii por el Mutor. Hiiwanl ]i. Adoliuann, I'liivorsidad Coiiicll. Itliafa.
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I'll caso cxtremo do espiiia l)ifida con lioinia dorsal en la ternera.
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El presentc trabajo es una dosoripci6n do un caso en el cual una porci6n de la nieinbrana mucosa intestinal emei"ge del cuerpo a travi's do lui orificio situado en la region lumbar de la cohunna vertclnal. ICste dofecto es una consecueucia de un defecto en la linca primitiva.
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Tnmnlation hy Jun^ P. Nonidci Cornell l'nivon»ity Mo<lirat Oilhiei'. N. Y.
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ACTHOR'S ABSTRACT OF THIS PAPER 18»UEl> BY THE BIBLIOGRAPHIC SERVICE, MAY 10
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AN EXTREME CASE OF SPINA lUFIDA WITH DORSAL HERNIA IN A CALF
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HOWARD B. ADELMANN
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Deparlmcnt of Histology and Kiiibrijolo(j>/, Cornell University, Ithaca, Xcw York
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TWO FIGURES
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The foetus forming the subject of this note is a part of the collection in obstetrics of the New York State Veterinary College and was siibniitted to me by Dr. B. F. Kingsbiny for an explanation of the striking and unusual anomaly which it presents. I was unable to find an exactly similar case in the literature of teratolog}'.
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The cases found in the literature which are to some extent analogous to the one about to be described are by (!urlt ('77), who gives an account of a calf embryo with a lateral prolapse of the abdominal viscera through the spinal column; "\'eraguth COl) described a human embryo with ectopia of the spleen and intestines. Finally, in 1917, Williams described a calf with the omasum and spleen extruded from an opening in the occiput. In all these cases the spinal defect is in or near the cervical region, while in the calf here described the defect occurs in the lumbar region.
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Unfortunately, the head and extremities of the specimen which I describe were removed before it was brought to the museum, "^riie musculature was removed and only that part of the vertebral column and viscera shown in figure 1 remained. No clinical history of the case is available. ■
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The sj^ecimen under consideration is a nearly mature calf foetus which exhibits two well-marked defects: 1) an extreme degree of spina bifida and, 2) a well-marked dorsal hernia.
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The cleft in the spinal colunm is com])lete and involves the entire lumbar region. X-ray ])hotographs show that the six
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29
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30
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HOWARD H. ADKLMANN
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luiiihnr vortelmic arc atTcctod and tliat halves of those arch arnuiui both sides of the defect, producing a somewhat triangular vertel)ral fissure. 7 cm. long and I? cm. wide at the cejihalic end. However, the area of comi)lete sphia bifida extends for only 2 cm. fron; the cephalic end of the defect; caudal to this point merely the verteliral arches are sei)arate<i.
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The vertebrae are more or less fused, especially in the cephalic end of the defect, where a bony prominence on the ventral side of the specimen gives evidence of this fusion. The tip ofthe transverse process of the sixth lumbar vertebra on the left side
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Kin. 1 Iilcnlizo<l snijittnl section of foetus to slmw the relations of the intestines. (', caerum; 1), dorsnl oprninK of the intestinal pad; /, intestinal I'ad; O, OS coxae; /?, rectum; S, blind .sac; -SV, spinal cord; \', ventral opening of intestinal pad.
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lies under the innominate bone. The spinal cord is divided, the resulting halves passing around the defect. Nerves are given ofT on each side.
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.\ pad of intestinal mucous membrane protrudes through the opening in the spinal colunm. "\Mien sectioned, this pad proved to be mucous membrane of the large intestine. Two openings in the mucous membrane, one dorsal and one .somewhat ventral, communicate with the large intestine (fig. 1). The dorsal opening is the larger and conmiunicates with a .small portion of the large intestine posterior to the caecum and with a blind pouch which also jjroved to be a portion of the large intestine when
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SPINA BIFIDA WITH DORSAL HERNIA IN A CALF
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31
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examined under the mierosrope. Ihe remainder of the large intestine, that is, the portion extending fiom the anus to the pad, ends in a small oiiening on the ventral side of the caudal end of the pad.
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Kig. 2 Dorsal view of the defect, showing the relations of the intestinal pad. D, dorsal opening of the intestinal pad; /, intestinal pad; 0, os coxae; R, rib; T, transverse process of lumbar vertebra ; V, vertebral column.
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The literature dealing with the causes of spina bifida is most extensive and the theories advanced are numerous. The theories of maternal impressions and amniotic adhesions need only be mentioned heie. The first has long been discarded and the latter theory has also Imhmi looked iijion as invalid, durlt (77),
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THE ANATOMICAL RECOKD, VOL 10, SO. I
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V2 HiiW \l;i( II. AUKI.MAN.N
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in jissinninn a causr for tlic coiKlition wliicli lie doscrihos, iiiontimis llic nillu'siniis of tho iiioiiil)raii('s cau.scil l)y tearing due to luniinti of tlio foetus. This is a rather vapjue exjilanation at l)ost. Modern invest ipators would more likely agree with ]\Iall, who says: "Sinc(> monsters are i)rodueed in animals without an anuiioii, it would l)e well, it seems to me, to relegate the anmiotic theor>- of the pnxluetion of monsters into the class into which that of maternal impressions has fallen."
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Of more imjiortanee, it seems to me, are the theories which regard a disturl)ance of growth metabolism as the causative factor in jiroducing abnormalities. The experiments of Hertwig, Morgan, ."^tockard, and others may be briefly mentioned.
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In IS'.fJ Ilertwig published his classical essaj' on "Uruiund und Spina Bifida," in which he showed that spina bifida could be producetl by the action of morj)hine. ^lorgan, in 1894, prfMluced spina bifida by adding O.ti per cent sodium chloride to the water in which eggs were developing. Hertwig, in 1890, found that salt solutions stronger than ().() ])er cent retarded develojiment and the eggs dietl witliout going beyond the gastrula stage. Similar results were obtained by Hertwig and Morgan by raising the temjierature of the water.
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(Jodlewski ('97, '00, '01) and Samassa ('96, '98) found that spina l)ifi(la could be produced through lack of oxygen. This might easily be the case in faulty implantation.
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lialdwin ('15) was able to produce spina bifida in ahnost every instance by treating the yolk portion of the egg with violet raj's. The action of the ultra rays, by destroying a portion of the yolk hemisphere, results in an upset of the balance between the (lifTerentiation of the neural canal and the approximation of the blastoporic lips. The differentiation is not retarded, and the half tuix's (lilTcrentiate into two tubes before the lips of the blastopore close.
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In the present instance, the defect un(|uesti()nably arose very early in the develojiment of the individual and is essentially the same as tho.se produced by Hertwig, in who.se experiments spina bifida or 'ring' embiyos resulted from incomplete approximation of the bl.'istfiporic lips.
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SPINA BIFIDA WITH DORSAL HERNIA IN A CALF 33
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There is no evidence that gastrulation in the calf is accomphshed by means of blastoporic Hps, but we may regard the primiti\-e streak as homologous with the blastoporic lips, since both give rise to spinal cord, notochord, and mesoderm. The opening, in this instance, may be a secondary condition which has arisen in the region of the potential neurenteric canal, the persistence of which has been recorded in numerous instances.
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The failure of the blastoporic lips (primitive streak) to approximate closely, differentiation, however, not being retarded, results in an opening bounded by material which becomes spinal cord, notochord, mesoderm, and perhaps a small amount of entoderm. In any case, liowever, the latter would adhere to the edges of the opening forming a passageway- into the primitive digestive cavity which may or may not coincide with the position of the potential neurenteric canal. Yeraguth ('01) regards the open neurenteric canal as the cause of the anomaly which he describes.
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The dorsal hernia which occurs in this specimen may be interpreted thus: There is a gap in the dorsal wall of the intestine at the primitive streak, and the ventral wall pushing up through the gap has produced a pad of mucous membrane such as here found. I regard the blind sac as an outpocketing caused by a fold in the intestinal wall. The steps in the formation of this dorsal hernia may be easily understood by consulting a series of figures given by Cullen in "The Umbilicus and its Diseases," page 224.
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It is interesting to note that spina bifida always occurs high up or low down in the spinal axis and to speculate why the defect should be so restricted. LebedefT's ('81) theory that the curvatures of the spinal axis disturb the normal de^-elopment of the medullaiy tube seems to be invalidated by two facts: 1) the neural folds have already closed before the body ac(]uires its normal curvatures and, 2) the cervical flexure is most pronounced, whereas spina bifida is most frequent in the lumbar region.
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In conclusion, I wish to thank Professor B. F. Kingsbury for many helpful suggestions; Professor W. L. WilHams, who loaned the specimen for descrijjtion, and Mr. R. R. Huinphrej', who made the drawings.
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V} ll<l\V\HI> H. ADEI.MANN
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HlHI.KiCliAl'lIV
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F^AI.^^VI^•, F. M. lOl.'i The action of ultia-violpl rays upon tlic fioc's ogg.
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Anat. Hoc, vol. 0, p. :J(15. Bai.i.antynk, J. W. ISO" TorntoRpiipsis: An enquiry into tlie ca\ises of monstrosities. Oliver \- Hoyil, I'Minlmrnh. Brom.vn, I. 1911 Norniale unil ahnoriiie KnlwickcUing des Menfclicn. ^'crlaR
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von .1. I'". HerKtiinnn, Wieslintlen. CrLLKN, T. S. 191(1 Tlie unil>ilieiis and its discase-s. W. H. Saunders Co.,
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I'hiladelpliia. (iobLEWBKi, K. mt)I Die Kinwirkung des SauerstofTes auf die Entwickclung
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von Rana teniporaria. .\rch. Ent. Mech., Bd. 11. Good, J. P. 1912 Spina bifida in the neck region of a ferret embryo 8 mm.
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long. Journ. .Vnat. and I'hys., vol. 46, p. 391. Cii-RLT, E. F. 1877 IVber thierische Missgeburten. VerlaR von A. Ilirschwald,
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Berlin. HERnvKi, O. I.S92 I'rmund und Spina bifida. .Arch, niikr. .\nat., Bd. .30,
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s. ,sef..
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Kkrmm-nkii, F. 19(19 Mis-^liildungen des Runipfes. In Vj. Schwalbe, Morph.
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der Missbildungcii, 111 teil, I. Liefcrung, 1. .\bt., 3 Kap., S. SO. Kkuikl, F., and Mall, F. P. 1910 Iluiiiau embryology. J. B. Lipi)incott
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Co., Philadelphia. Lebkdkfp, a. 1881 I'eber ilie ICnt.stehung der Aneneephalie und Spina bifida
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bei Vogeln und .Menschen. Arch. path. .Vnat., Bd. 80. LiLLiK, F., AM) KxowLToN, F. P. 1897 On the effect of temperature on the
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development of animals. Zool. Bull., vol. 1, !>. 179. .Mall, F. P. VM\S \ study of the causes underlying the origin of human monsters. .Jour. Morpli., vol. 19, p. 3. MoR(iAN, T. n. 1S97 The development of the frop's ckk Mncinillati iV: Co.,
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New York.
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19O2-10(tt .Several papers in Arch. Ent. Mech., Bd. 15, 10, IS, 19. Stockard, C. R. loot) The development of Fundulus heteroclitu.s in solutions
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of lithium chlorid, with ap|>pnilix on its development in fresh water.
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Jour. Exp. Zo(>l., vol. 3.
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1907 The artificial production of a single median eye in the fish embryo
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by mean.-* of sea-water solutions of magnesium chlorid. Arch. ICnt.
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Mech., Bd.23. Veracuth. O. 1901 Teller nieder diffcrenzirte Missbildungen des Ccntral nervensystems. Arch. Ent. Mech., Bd. 12. Wmkklkr, T. 1918 Study of a human Spina bifida monster with encephaloceles
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anil other abnonnalitics. Contributions to Embryology, no. 22, vol.
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7. Carnegie Institute of Washington. Williams, \V. L. 1917 Veterinary obstetrics. Published bv the author, Ithaca,
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N. Y.
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Rosiimcii ])()r el autnr. H. M. Stroiifi. Escuola do -Mcdiciiia dc la I'niversidad Loyola, Chicago.
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Sobio un iiiodcio pcoii6inico de los priiK-ipales tractos de la niodula cspinal y tallo cerebral.
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Este niodelo incluyo dibujos de secciones transversales (auniontadas ocho diaiiiotro.-^) practicadas on cuatro iiivolos de la iiu'dula y on sieto iiivolc.>< del eje cerebral, inontadas ^iobre un tabloro de diez pi6s de longitud y un pi6 de anchura. Para ropres(>ntar lo.s tracto.s mas inii)ortantes se eniplean cintas coloroadas. El problema de indicar el trayecto de los tractos entre ol tallo cerebral y el corebelo se resolvio colocando un arco .><obre la regi6n del puente. En este arco se insertan los tractos con conexiones corobelo.^as, represent ados por cordon(>s coloroados. Los niateriales enipleados en este niodelo sujjonen un gasto mfnimo. Este modelo ha sido usado con gran provecho por varias cla.se.s, siendo especialniente util para la i)t)tenci6n de conceptos sobre la proyecci6n de los tractos.
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TnnwUtioti by JfWi F, Nonidoz Comcll I'nivfmity .Mfdiriil Coll<'«i-, .V Y.
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ATTTHOR 9 ABSTRACT OF THIS PAPER ISSUED BY THE BIBLIOGRAPHIC SERVICE, MAY 10
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AN INEXPENSIVE MODEL OF THE PRINCIPAL SPINAL CORD AND BRAIN STEM TRACTS
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11. M. STRONG Deparlmcnt oj Anatomij, Loyola University School of Medicine
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TWO FIGURES
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The apparatus described here has been useful in heli)ing my students in the difficult work of learning the tracts of the cord and the brain stem. It is especially helpful in getting projection conceptions, and it involves Uttle expense.
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Drawings with a magnification of eight diameters were made for four levels of the cord and seven levels of the brain stem, the last being through the diencephalon. These drawings were made on light bond typewriter paper, and thej^ were pasted on light binding board to produce what will be termed sections in this paper. In order to have the structure outlined A-isible on both faces of each section, a reverse copy of each drawing was made. This was accomplished by tracing the second drawing for each section on a piece of paper which was held against the back of the sheet of paper bearing the drawing. The two sheets were placed against a window pane with the first drawing against the glass. With sunlight transmitted through the two sheets, it was easy to make the tracing.
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The pictures can of course be made by photography or with the aid of a projection outfit. A pantograph can also be used to advantage in getting a desirable size for the drawings.
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A board 10 feet long and 12 inches wide was used as a base; it was stained and varnished. The sections were mounted on the board by means of strips of galvanized sheet iron (figs. 1 and 2) These strips were cut 1§ inches wide by 4^ inches long. Each strip was bent so that two limbs making a right angle with each other resulted. One of these limbs, 3| inches long, was fastened
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'M\ H. M. STRONG
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to tlif Ixiarti hy scrows. Tho otlicr liiiil), 1} inches liif>;h, has a vertical jiosition. Two ])airs were used for each section, and thoy were inountcHl so that tlie vertical limbs had just enough space l>ctwoon them to insert the l)ase of a section with a tight fit.
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Before mounting, holes were ma<le in the horizontal limbs for the screws used in fastening them to the board. It was not found necessary to fasten the vertical limbs to the sections as tlie tiglit (it antl the strings employed in the model hold the sections in place.
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There is a tendency for tlie sections to be pulled away fioni a vertical i)osition by the taut strings. This difliculty was met by using a piece of white string as a stay line. It was attached to the top of each section at its middle and was tied at the ends of the board, after being made taut.
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("()h)red strings were used to indicate tracts, and they were fastened at their ends to nails. A tract not extending the whole length of the cord, for instance, is represented by a string which was deflectetl beyond its last level in the model to a nail at one side.
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Descending tracts are represented by red strings, exteroceptive liy blue, projirioceptive by yellow, and association tracts by purple. The colors fade eventually and become dull from .soiling, in which ca.se it is a very simple process to substitute new strings for the old. The regions occupied by the tracts are indicatetl diagranunatically with corresponding colors in the drawings.
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'I'he ccrel)ellum presented a jieiplcxing problem in constructing the model. This was finally solved by placing an arch as se<'n in figure I over the pons regi(m. Tracts passing through the restiform body, brachium pontis, and brachimn conjunctiviim are represented by strings which have the cerebellar ends attached at the top of the arch.
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Decussations are re|)resente(l in the drawings by the usual methods ((ig. 2). In the ca.se of the strings, the problem was solved by passing the string across the face of a section in the region of the deeu-s.sat ion in question. The section is perforated three times by each string in such eases instead of once. The
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MODEL OF SI'i:^AL CORD AND BRAIN STKM TRACTS 37
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Vrf'h I'cr r-tTt^lM'llniil
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Fig. 1 View of entire model Fig. 2 View showing region of fillet and pyramid decussations
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.■* moilel is large enough to permit a number of students to study it simultaneously and it is in almost constant use during laborator)' periods. I have not labeled any part of it, as I prefer to have the students identify the structures represented. A limited amount of a.'^.-^istance ui interpreting the model is given.
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Hcsimion por c\ alitor, .lacoli l^cif^lianl. Pfpartaniriilo dr Zoolo^fa, riiivcrsidad dc -Michigan.
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K! alniacenaniioiito y inanojo de cuadros murales.
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Va\ v<>z dc los listoncs do niadora (\nc so usaii ordinariainonte, ol autor oiiiploa listoiios do inadoia "hasswood" tefiidos con crcosota. Las diiiionsioiios do ostos listonos son ', dc pulgada dc cspesor por ] do pulgada dc anchura. So olavan ostos list ones a los cuadros onii)loando clavos de alanibie de ] pulgada de diaiuctro, y dol)ajo dc las cabezas de dichos clavos se perforan oiiaiirados do liiorro jiahaiiizado ilel nuni; 28. Los list ones ocupan la supoiHoio anterior do cada cuadro y los olavos se clavan on los lados libres. Cada list6n superior ilcv a iin fiaiiclio Hndjio atornillado en el centro del list6n. Cuando se hace ^irar al ^inx'bo dc niodo quo venga a coincidir con el piano de la lamina, sine para oolfjar osta ultima de una barra dc hierro colocada on ol cuarto on donde se guarden las laniinas. De osto niodo ostas so cons(>rvan sin arnifjas, y puosto i|Uo los listoncs ooujjan nuiy poco espacio, puodon oolfjarso todas ollas dc un mode seniejante al de las hojas de un libro suspendido por el lomo. I-as laniinas se arreglan en ordcn de materias j)or medio do minicros. como si se tratase dc un catalogo de materias, y cuaKiuiora <le ollas puede faoilmcntc sacarse y volvcrla a su .sitio. Cuando se necesita usar una dc las laniinas se hace girar ol ii.anclio i)n graflos, y entoncos puodo oolgarso do un l)astidor, alanibro o cualiiuicr otro sojjorto on la claso. Algunos de los mccanismos descritos han venido usandose hace largo tiempo; otros son nuevos. Sirven para coleccionar himinas de todos los tamanos en un espacio mfnimo y para podcrlas guardar en onion y oniploarlas invirliondo ol monor tiempo i)osil)lo. Kl prcsente trabajo indica dondo puodon obtenerse los materiales omploados y su coste.
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TraiwUtinn hy J(m^ K N'oDJftra Cornfll ('ntvfniily Mrfliral Oftllrgr, N Y.
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author's ABeTRACr OV THIS PAPEH ISHL'KD BY THE BIBLIOCKAPHIC PEKVICK, MAT 10
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THE STORAGE AND HANDLING OF WALL CHARTS
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JACOB REIGHARD
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Dc pnrlmcnl of Zoology, University of Michigan
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FOUR PIGUKES
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The maker usually supplies charts with wood rods tacked and glued to the ends. In use they are hung from hooks on the \\all of the lecture room by means of two metal rings tacked to the upper rod. When stored they are rolled and tied about with tapes. In the Zoology Laboratory of the University of Michigan we have tried probably every known device for the storage of rolled charts. They may be jiiled on racks such as once were used at Harvard rni\'ersity. To make these, pieces of round iron, some 30 inches long or more, are bent for a couple of inches at the ends, flattened and drilled at the middle, and screwed horizontally to wooden uprights to as to project on both sides like large coat hooks and form two ladder-like sets of supports. On two such uprights, properly spaced, one may store man}' charts and classify them roughly. The uprights may be built on a base with casters beneath it and the whole contrivance wheeled from place to place. Labels may be written on discs of cardboard tacked to the ends of the chart rollers. As the charts accumulate and are piled sevei'al deep on each support, it is impossible to keep them in o'rder and much time is wasted in locating and reading the small labels. In spite of the most ingenious labeling it is often necessary to unroll the charts to find those that are suitable, and this entails not only loss of time, but damage to the charts.
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To find the charts more readily, we have tried supporting them on pairs of large iron hooks screwed into vertical wood strips nailed to the walls of the lecture room. The charts then lie in one plane like the rungs of niuiierous ladders set agamst the wall. They may be classified and labels put beneath the groups. But
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39
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40 JACOB REIGHARD
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as the colloftion grows it takes imicli wall space. It may beroiup necessary to cliiiil) to reach the uppermost charts and thej'^ have still to he uin-oilcd.
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In place of sup|)ortin{t the roiled charts on metal rods, one may use deep wood frames divided into comi^artments like the hoxes in a post office. These may l)e arranged to hold tlie charts in vertical or horizontal position, l)ut we have found this plan as cumbersome and wasteful of time as the other.
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Home-made charts accunmlate in every laboratorj'- and are apt to be of various sizes and of material that deteriorates if kej)t rolled and frecjuently unrolled. To avoid the labor of attaching them to rollers, one is tempted to let them lie flat, and we have piled them thus in large cases with numerous close-set shelves on which they maj' be roughly classified. It is not easy to label such charts so as to find readily what is wanted, and in pulling one from a pile for examination it is likely to be torn or damaged by rubbing. To return it to its proper place the whole l)ile must l)e taken out. Naturally one puts the chart back on top of its pile or on top of some otlicr jjilc and tlic wliolc collection is thrown into confusion. In addition to this, if .some charts are kept flat and others rolled, there are two places to look and time is wasted in the search.
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In hanging the charts for use the two rings at the top must be put over hooks on the wall of the lecture room. To accommodate the unequal spacing of the suspension rings of dilTerent charts, the hooks mu.st be movable. One may suspend picture hooks from a molding or wire and slip them along until the su.speiision rings of the chart will go over them and one must climb a ladder to do it. One maj' dispense with the ladder by using a wooden frame filled with wire netting and arranged to be raised and lowered by ro|)es and i)ulleys. The picture hooks may be stuck into the lowered netting at suitable intervals, the chart rings slipped over them, and the whole thing hoisted, or one may cover the hfiistable frames with cotton cloth and pin or clip his charts to that.
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.\fter trA'ing most of the plans outlined, we sought a means of keeping all charts in a minimum space in one collection with
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STORAGE AND HANDLING OF WALL CHARTS 41
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out rolling them and so that they could be classified and examined and each removed and I'etiu'ned without disturbing the rest. We sought also the easiest way of hanging them for use. The result combines the unj^ublished devices of friends with some of my own. The universities in which 1 have seen some of these devices in use are indicated in parenthesis. I do not know that any other consistent scheme has been described in print.
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We now store all our charts together by hanging them from a piece of f-inch iron pipe supported from the ceiling by a wire and stayed by wire to the side ^^all (^Visconsin) . They are in a small room reserved for the purpose. The charts hang flat, one against another, like the leaves of a book. Because the wooden rods take too much room, we ha^-e remo^'ed them and have substituted thin strips of basswood (fig. 4, chart at right.) A thousand of these j x f inches by 40 inches, cut at a planing mill, now costs $18.00. Probably any good soft wood would answer, but hardwood warj^s so that the strips do not stay flat. The strips are stained bro\\n by dipping in creosote. They are tacked to the face of the chart along its ends bj^ means of ^inch wire tacks or clout-nails set from 4 to 6 inches apart and clinched on the free face of the strips. To keep the heads of the nails from tearing through the charts we have put under each a piece of 28-gauge galvanized iron. This is | inch square, perforated at the center, and has the corners turned with pliers to as to form small points that penetrate the chart and go a little way into the wood. We find it better not to use glue, and none of our charts attached to the strips by tacks in the manner described has yet come loose from its supports. A piece of sheet iron 2x2 feet now costs fifty cents, and from it about 1000 squares can be made in the laboratory.
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For suspending the charts we use the hook de\-ised by Prof. C. F. Hodge. It is screwed into the upper strip at such a point as to make the chart hang level. When the hook is turned into the plane of the chart it serves to suspend it from its support in the chart room as a suit of clothes is hung from a rail (fig. 1). ^^^len the chart is to bo used, the hook is turned through 90 degrees and may then be slipjied over a picture molding, wire, or other
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42
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JACOU RKICillAKK
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e a
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c
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^ ^^'^^\
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c
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STORAGE AND HANDLING OF WALL CHARTS
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43
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support in the lecture room. To hoist it into place and get it down again, we use a light wood pole Oi feet long, also Professor Hodge's device. At one end the pole is provided with a ferrule through which is driven the sharpened end of a piece of f-inch round-iron. This is bent as shown in figure 8 and has its free end slotted to form a pair of claws like those on a tackhammer. The hump on the suspension hook fits between the
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d
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Fig. 2 The Hodge hook. See text Fig. 3 Pole for putting up and taking clown charts. For description, see text
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claws on the pole and permits the chart to be handled without waste of time. In each lecture room a short suspension rod is provided. To this the charts are transferred after use and from it an assistant collects them from time to time and returns them to the chart room. The Hodge hooks were obtained from the Wire Goods Co., Worcester, Massachusetts, and cost, before the war, $1.35 per gross. The iron claw may be made by any blacksmith.
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THE ANATQMICAI. RECORD, VOL. 19, NO. \
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I I JACOU UKIfillAIlD
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KordisplayiiiK cliarls in tlic IcH'tmv room we have uschI a niodifipil form of a dovicc made for displaying buRSy rnlus, and nso<l for charts at tin- I'nivcrsity of Wisconsin. As used l)V us, tliis tlovicp consists of eighteen wood arms, each supported by an iron riMl. and arranged to swing Hke tlie arm of a derriclc (fig. 4). 'Ihe arms are pivoted to steel sectors which turn on the central u|)right axis, hy turning the sectors all the arms maj' be thrown either to right or left. Kach arm supports two charts back to back. .\ny one of these may be brought into view by turning the arms as one turns the leaves of a book held vertically. The device may be attached to the wall, as ours is, or caiiied on a movable base resting on the Hoor. It nuiy be obtained from .h.lm Best. Calva, Illinois, and cost (in lOlo) .SID.OO.
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The whole arrangement has proved very satisfactory. The charts are designated liy tlic numbers of the Concilium Bibliograjihicum gunuucnl to the u|)per wood strip (fig. 4). They are arrange<l on the rail in .systematic order, and any one may be locate<l, removed, inspected, and returned to its place without difliculty. To subdivide them, index labels are hung at intervals (fig. 1). The.se are wood strips suspended from the rail l)y Hcxlge hooks. '1 hey project beyond the charts at one end and each liears at that end a square of chart cloth with an aj)])ropriate label and at the opposite end a thin bag of sand to balance it. Charts of any ordinary size may be accommodated. \'er>- large maps may have to be kept rolled in a separate place, but they may be represented in the chart collection by appropriate dummies on which are written references to their location and to which may be attached |)hotograi)hs of them. Our collection consists now of 'Mi) charts vaning in size from 2x2 feet to 5J X 'A feet and made of various materials. These occupy in storage a s|)ace 1 1 feet long, but the same space will probably aoconinHMlate nearly twice as nuiny and .still pemiit anyone to be exaniini-fl in situ. If longer hof)ks were used the charts could be hung alternately high and low from parallel sujiports so that the wood .strips would not be opposite. The .same .space would then accomnKKJate manv more.
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STORAGE ANO HANOLIMG OF WALL CHARTS
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45
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-I() JACOn REIOHARD
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As our polloction grows wo shall make a cartl cataloniio of the charts ill which oacli chart will !>(> rciiroscntcd hy small jjhoto^laphs I I'ciiiisyUania). Hy attaciiiiij!; (■(incilium mimluTs to the (lu|)licate photographs aixi anaii^iiig them according to the concilium system, cross references will he made to many of the charts, thus the chart shown at the right in figure 4 would he represent(Hl in the catalogue hy several photographic cards, each of which would hear an identical nuniher to show the location of the charts in the collection. These cards would l)ear also distincli\-e concilium numhers hy which they would he placed in the catalogue under Crustacea, emhryology. and under one or more anatomical designations.
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Hosuinon por el autor. Roy Lee Moodie, Departainento cle Anatoniia, I'niversiclad de Illinois.
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I,a naturaleza del sistema Haversiano priniitivo.
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Los huesos mas antiguos, encontrados en el Silurico y el Dev6nico. careoen de A-erdaderos sistemas Haversianos, que se desarrnlhui prinieraniente con cierta extensi6n en Diiiichthys, del Dev6nieo. En este pez aoorazado alcanzan el niiixinio de desarroUq en Ponexi6n con el proceso dentario de la maxila y preinaxila. Las lagunas ])aiticipan de la. naturaleza de los od(niti)l)last(»: los canalfculos nunca comunican entre sf; la laniinilla filnilar existe: las filjias ]ierfoiantes no se han desarrollado: el canal central es ancho. El polarfscopio es litil para distinpuir la naturaleza de los sistemas Haverisanos priinitivos. No existen pruel)as sobre la evolucion de la estructura liol luieso; se percibe un canibio Ijastante brusco con la introducci6n de la-s fonnas de mamfferos.
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Trannlation by Joe*^ F. Nonidcz r.,rii.ll Itiivrr.itv M.ili.-nl CIL-Bt . \. Y.
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author's abstract of this taper issued by the bibliographic service, may 10
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THE NATURE OF THE PRBIITIVE HAVERSIAN
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SYSTEM
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ROY L. MOODIE
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Department of Anatomy, Uniocrsily of Illinois, Chicago
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ONE PLATE (three FIGURES)
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The term Haversian sj^stem is necessarih* of ^-ery general significance and is used in a broad wax to distinguish any concentric arrangement of osseous lamellae around a central canal. It is often difficult to distinguish between a dentinal system, that is, a concentric arrangement of dentine, around a dentinal tubule and a true Haversian system as seen in long bones, since the two often grade into one another. The presence of lacunae does not seem to be essential to an Haversian sj-stem, though they usually are present. In the fishes, both modern and ancient, osteoid tissue, largely lacking lacunae, may arrange itself around a vascular opening and thus have all the appearances of an Haversian system, and give the same orthorhombic light reactions under polarized Ught.
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The type of such a system may be taken as those most highly specialized Haversian arrangements seen in the long bones of man, especially in the femur. From this complete system down to a slight lamellar arrangement of substances one may find all gradations in a series of fossil bones representing the history of the vertebrates from the Devonian to the Pleistocene. Such a review has been made, and it will doubtless be of interest to describe and illustrate the most ancient Haversian sj-stem of which we have any knowledge.
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There is no apparent indication of a gradual evolution in form of the Ha\'ersian system from the most ancient vertebrates to modern mammals, although there is a gradual de^•elopment in the form of the lacunae and canaliculi. The reptiles do not
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47
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48 nOY I.. MOODIE
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show a higher typo of Haversian system than do the ani|)liiljians or fishes, as they do in their skeletal organization. Haversian systems in dinosaurs are as primitive as they are in Devonian fishes. They seem to have sprung into existence full formed without undergoing the proce.ss of evolution such as has obtained in the bodily organization of the vertebrates.
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The most ancient organization of osseous elements which simulate an Haversian system are to be found in the dental i)rocess of the premaxilla of a Devonian arthrodire, Dinichthj's (figs. A and Hi. allied by some paleontologists with the lung fishes. This arraiigom(Mit is well known to paleontologists and has been descril)cil by Claypole (94). These curious structures arc not present in other portions of the armor of Dinichthys and are to be regarded as specialized dentinal sj'stems, though not found in the true teeth whicli are not connected with the cranial skeleton. 'Ihe Haversian canal resembles a dentinal tubule, the the lacunae are those seen in the cementum of modern fishes, the lamellae are fibrillar and partake of the characteristics of dentine as seen in the teeth ifig. C) of Carboniferous sharks, the interlamellar sjjace is filled with cement and there are true interstitial lamellae, though never any of the type due to the partial ab.sorption of other Haversian systems. I have not seen this tyjje. known as false iliterstitial lamellae in any fossil vertebrate. The orthorhombic light reaction under polarized light is exactly like that of the highly specialized Haversian systems in the fenun- of man. The canaliculi from the lacunae conununicate neither with each other nor with the central canal, nor do they do so in any fossil vertebrate below the mammals. The lacunae are not confined largely to the interlamellar spaces, as they are in mammals, nor is there any apparent i)lan in their arrangement. Often, as in a Permian reptile, one finds three lacunae grouped together, surrounded on all sides by wide areas of osteoid tissue lacking lacunae.
 +
 +
The use of polarized light is essential to an adequate understanding of the structure of fossil bone, since usually under polarizatirm, lamellae, fibrillae, canaliculi, and other minute histological units, invisible under ordinaiy light, stand out with
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 +
 +
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NATURE OF PRIMITIVE HAVERSIAN SYSTEM 49
 +
 +
startling distinctness. The importance of this has been commented upon by various authors in their studies on the histology of fossil structures.
 +
 +
Arey ('19) has recently called attention to the presence of Haversian systems in the membrane bones of man. The systems he described and figured, however, cannot be called true Ha\'ersian systems, but resemble those seen in fossil reptiles. It is interesting to note in the temporal bone of an Oligocene mammal an arrangement of substances exactlj^ similar to those described by Arey for man. These intermediate or pseudoHaversian systems often fail to give an orthorhombic light reaction, as thej^ do in the case of the Ohgocene mammal. The difference between the true and the intermediate types of .systems is to be found in the absence of intercommunications of the canaliculi with either the central canal or other lacunae and in the occasional failure to secure the same light reactions. In all other respects they are similar.
 +
 +
The review was undertaken with the idea of gaining a conception of tissue organization in ancient vertebrates so that I might judge as to the disturbing effects of pathological processes upon the structure of the part. The presence of osteoid tissue in ancient vertebrates is a normal condition. Kolliker f'.57) noted that many fish bones are composed entirely of osteoid tissue. One interesting effect in pathological conditions of fossil bone is to stimulate the growth of pseudo-Haversian systems, and to increase the vascularity of the bone. The same fact has been noted by Foote ('16) in the fractm-ed femm- of a frog, where Haversian systems are ordinarily absent.
 +
 +
SUMMARY
 +
 +
Prhnitive Haversian systems of the very ancient vertebrates differ hut slightly from highly de\'eIoped sj'stems of motlern mammals and have been but slightly modified by the passage of time. Each group of vertebrates has its own tj'pe of lacunae, but the organization of the Haversian systems remains the same. The concentric arrangement of lamellae is not an incident of
 +
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 +
.")() ROY L. MOODIE
 +
 +
evolution, but a ri'spousc to the iiicchaiiical laws of organization of the |)aii. True Haversian systems are confined to the niannnals.
 +
 +
A more complete account and more adequate illustrations will be found in the A\'illiston Memorial \ olume now in preparation.
 +
 +
BlBLIOC;RAiniV t Arf.y, L. B. 1910 On the presence of Haversian systems in membrane tjones.
 +
 +
Anal. Her., vol. 17, i)p. .59-62. Claypolk, E. \V. 1894 .Structure of the bone of Dinichthys. Proc. .Vnicr.
 +
 +
Micros. Hoc, vol. 1,5, pt. .i, pp. 1,S9-191, figs. FooTE, J. S. 1916 Comparative histologj- of the femur. Smithson. Contrib.
 +
 +
to Knowledge, vol. 3.5, no. 3. K(iLLiKEK, A. 1S.57 On the difTerent types in the microscopic structure of
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the skeleton of osseous fishes. Proc. Uoy. Soc. London, 18,57, vol. 9,
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pp. 6.5G 068.
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yi
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PLATE
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PLATK 1
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KXl'LANATIO.N OK UliUHKS
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A A (icld in u «ccti()n uf the prcmaxilla of Dinichthys,a Devonian A it li rod ire, showing the distribution of the oldest known representatives of the Haversian systems. Between adjacent systems are to be seen interstitial lamellae. Two systems, at the lower left-hand corner show the concentric lamellae. X 70
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B A single system showing large size of central canal, concentric lamellae, distribution of lacunae and nature of ground substance, which under polarized light is seen to be fibrillar. The bhiMc band at the left lower corner is a postfossilization crack and has no significance in the histology. X 300
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C Dentinal tubules of Mazotlus, a carboniferous shark, for comparison with the spei-ializcd syslein- in Diiiiclillix s :iliove. X 70.
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nOY L- MOODIE
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33
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Uc'siiHiCii ])()r el autoi-, HulHTt Shcppanl, DopartanuMilo do Aiiatoinia, I'liivorsidad dc Kansas.
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Heniuifroditisiiio on ol Honihre.
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I'ji el hoinl)ro, el herniafroditisnio con existencia de teslfculos y ovarios nonnahnentc desairollados en el misnio inilividuo aparece raias veces. En el iiidividuo tlescrito en el prosente tial)a.j() los testiVulos aparecian on ol oscroto y los ovarios on la eavidad pelvica. Kl tejido que fonnaba anibos 6rganos era normal en ostruotura en todos sus d(>tallos. So podia distinfiuir pcrt'octanionte una pared niuseular utoiina (juo liniital)a una ravidad ([ue deseniboeaba en la vagina. Las tunicas del conducto deforente y el oviducto, asi como sus cavidades podian taiiil)i<'n distingnirso. Kl ciiello del ntero ocupaba casi exactanionto la jjosicion del utri'culo proslatico do! varon. Kn todos los cases do liennafroditisnu) se ha podido comprobar una distinci6n niarcada entre los tojidos genitales niasculino y femenino, .sin encontrarse nunca una niezitia indotinida de anibos elonientos (es decir, un verdadero ovotesticulo). Kn el raro caso doscrito encontrannos el mismo fonuinono cini una soparacinii .-lun mayor do las (los dasos do tojido, ])uosto (|Uo los tosti'cuios y ovarios ocuj)ai)an su jjosicion normal correspondicnte.
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Trnnjilatinn by Joe* F. Nnnides Cnrnrll Onivi-raity Mrcliriil CViIli-KC. N. V.
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AtTHOn's ABSTRACT OF THIS I'AI'KR ISSUED l(Y THK BlBLlOcnAPHTC SF.RVICK, MAY 10
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her:\iaphroditis.m in man
 +
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HUBERT SHEPPARD Deparlmcnl of Anatomy, The University of Kansas
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SEVEN FIGURES
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An opportunity to make a study of the anatomical structures of the genital organs of hermaphroditism in man is seldom found for two reasons: first, such irregularities seldom occur and, second, when they do occur the material is exceedingly difficult to obtain for laboratory purposes. As recently as 1911 it was asserted that "hermaphroditism in the sense that separate testicles and ovaries are found has not Ix'cn demonstrated in man, nor even in other mammals beyond a <luubt."" We thought it worth while, in the light of this and other in^•estigations, to report a study of the anatomical structures of an extreme case of hermaphroditism Avhich came to the dissecting room. The gross study is supplemented bj' microscopical examinations in so far as the condition of the material would permit.
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The cadaver featured, objectively, both as a male and as a female subject. Hair was lacking on the face and scant around the genitals, the body was large and obese, with the mammae well developed, large and flabby, which in every way resembled a female rather than a male organ. One would have judged, in so far as the external genitals were concerned, that they were male rather than female genitalia. However, upon a closer examination, one could see that there were certain irregularities. The penis was small with a dilated urethral orifice three-fourths as large as the organ itself (fig. 1). The scrotum appeared to be abnormally large, although the testicles, upon palpation, were found to be normal and synunetrically formed. When the region posterior and beneath the scrotum was palpated, its apparent unusual size was found to be due to a large fold or ridge which extendeil from near the anus to the pubis on either side of the penis.
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55
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56 HUBERT SHKPI'AUD
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THE FKMALE EXTERNAL GENITALIA
 +
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After (lie skin and scrotum wore completely reflected from the urogenital triangle, the large ridge beneath the scrotum was found to l)e a structure which res(Mnl)Icd female external genitalia. Hiiili till- lai)ia niajoTa and minora were nearly nornial in size, the former extending to the posteiior connnissure, while the latter formed the fremdum. The skin and dartos of the scrotum di\ided into two lamina on reaching the postero-inferior part of the labia majora. The superficial layer continued as the skin and fascia of the f(>moral region, the imier lannna thickened into the labia majora. The nunora was two mendjranous folds within th(> majora and surrounding the penis or enlarged glans clitoris. M this stage of the dissection, if one would disregard the latter enlargetl organ, the cadaver was nearer a female than a male subject.
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Tin; I'ENIS AND VACINA
 +
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The penis in all i('s|)ecls resembled a glans clitoris which had develoi)ed into an organ that closely figured externally as male genitalia with a cone-shaped dilated urethra (fig. 1). At the large or vaginal end of the urethra was an ojiening that extended back into the uterus through the prostatic-cervix of the uterus (fig. 2), which will be descril)ed later. The penis was small, mea.suring a little more (li;in 1' inch in length and \ inch in diameter. The glans had a pr('|)uce fuseil with the erectile tissue of the corpus cavernosum. and was only a rudhnentaiy fold at the end of the organ. The dorsal vein, arteries, and nerves were regular and similarly related as those found in a normal subject. Kxternally, the urethral orifice of the corpus cavernosum urethra (fig. 1), measured ^ inch in diameter. This opening gradually increased in diameter until it was a little more than an inch in diameter at the urogenital dia|)hragm. In so tar as we could note, there was no s])ongiosum tissue present in the mrtlnal i)art of the organ. Both the urethra and the vagina opened into this enlarged urethra. The true urethra
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HERMAPHRODITISM IN MAN 57
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itself was only about f inch in length. This duct passed through the upper part of the prostatic-cervix portion of the uterus, while the \'agina was located in the lower two-thirds and extended up\\ard and backward into the uterus proper. Posteriorly, the corpus cavernosum penis divided into two short crura (fig. l) f inch in length.
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THE UTERUS
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The body of the uterus was separated from the bladder by the vesico-uterine fold of peritoneum in the usual manner. However, the uterus as a whole was somewhat lower down in the pelvic cavity than is ordinarily found in normal cases. This was due possibly to the development of the organs — the fusing of one genital system with the other. The greatest width of the uterus was 1.5 cm., with a total length of 5.5 cm.; the body was 4 cm., and the prostatico-cervix 1.5 cm. A uterine body cavity was perfectly developed, and measured nearly 5 cm. This cavity extended into the uterus with little demarcation between the two organs. The entire cervix was fused with the prostate; in fact, the prostate was a mere enlargement of the cervix of the inferior extremity of the uterus. The uterus held the same relation to the prostate that utriculus prostaticus holds in a normal male subject. Not only the lumen, but the uterine glands and muscular walls could be easily defined (fig. 3). The ductus deferens entered the prostatico-uterine canal of the cervLx by piercing its posterior wall (fig 2). A broad hgament was well developed, resembling in every detail a normal female subject except the course of the ductus deferens, which will be described later, and it was a little thicker and wider, due to the fact the uterus was a little lower in the pelvis as has been previously described.
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THE DUCTUS DEFERENS
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The ductus (vas) deferens differed in no respect from a normal male subject until it passed through the annulus inguinalis abdominis in connection with a very rudimentary ligamentum teres uteri (fig. 2). It then coursed alongside, and posterolateral
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THE ANATOMICAL RECORD, VOL. 19, NO. 1
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5S HUBERT SHEPPAUD
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to the oviduct, at tii>;l encircliiif; iIk- ovaries. When it readied the level of the uterus, it made a quick S-.shaped turn, and entered the .superior part of the cervix of the prostatico-uterus. The hi.stolopical structures of the duct are veiy well developed. The epithelium surrounding the lumen is slightly disintegrated, a.s is shown by the photograph The circular and longitudinal muscle layers are clearly defined, and in a number of sections the tunica projiria and the inner longitudinal layer are also easily recognized (fig. 4).
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THE OV.\RIES .\ND OVIDUCT
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The ovaries mea.siu-ed about 1 inch in length and ' (> inch in breadth. They were attached to the mesovarium in the usual way. However, the ovaries were found to be in a poor state of jjreservation for hi'^tological purposes; nevertheless, some of the materials stained sufficently well to demonstrate the ovarian tissue. One of the larger follicles as well as a number of smaller are shown in figure 5. .\ little below the folicles is a light area where the corpus lutoum has disintegrated from the rest of the tissue.
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Each oviduct took a nornuil course to the proximal opening into the uterus (fig. 2). The course of each duct was at first almost horizontal, lateral, and posterior from its attachment to the uterus until it reached an inferior lateral portion of the pelvic wall where it came into relation with the uterine extremity of the ovaries. Then it coursed at right angles, and passed almost vertically upward along the mesovarial border of the ovary to the mouth of the infundibulum and the fimbriated extremity of the duct. Microscopically, the sections of the oviduct very clearly difTerentiated the various tunics; the serosa, the longitudinal, and the circular miiscle layers show with marked clearness (fig. ()). The ei)itliclium as well as the inner i)art of the mucosa has somewhat disintegrated from the lumen. It was jKissible in many of the sections to define the epithelial cell structures. .V lumen extended throughout the full extent of the duct.
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HERMAPHRODITISM IN MAX 59
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THE TESTES
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The testes did not differ from a normal testicle, except in size. The right testis measured IJ inch in length, f inch in breadth and 1 inch in diameter anteriorposteriorly. The left testis was nearly the same size as the right except for length. It measured a little more than l-^- inch. Each testis lay upon and slightly laterally to the large ridge or fold beneath the scrotum. This arrangement gave the scrotum its extremely large appearance when viewed in its normal state. The funiculus spermaticus had all of its usual structures, even the pampiniform plexus was easily worked out. A small round ligament, before mentioned, was fused with the fimiculus as far as the point where the labia majora began. At this point it was lost and could not be traced any farther along the cord.
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This tissue, like the ovaries, was in a poor state of preservation for histological study. However, in many of the sections the convoluted tubules could be easily differentiated (fig. 7). Only the shape of the tubule with its contents could be clearly defined. It was impossible to differentiate between sexual and sustentacular cells except in a few sections. In these better sections, a few interstitial cells could be observed under oil immersion.
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DISCUSSION
 +
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According to Virchow, this individual subject would be an individuum uterusque generis, since both male and female organs are found almost equally developed. Klebs regards a hermaphroditismus verus as a subject who possesses both male and female genital organs united in it. In the spechnen under consideration, we find two set;; of reproductive glands. They were not united in the sense of ovitestes, but since both the ductus (vas) deferens and the oviduct (Fallopian tube) enter the uterus and, further, the round ligament and the spermatic funiculus have a union as well as a natural position and course, we can say that there was an indirect union. Even according to Kleb's definition this would be an hennaphroditisnms verus.
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(K) HUBERT 8HEPPARD
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nuilornatsch says that "herinaphnMlitisni in the sense that separate* testicles and ovaries are formed has not been demon8trate<l Ix-yond doubt." Except for minor variations which we have previously describe<l, we find not only separate testicles and ovaries which are in their noniial position in the body, but also a complete male and female urogenital system with the exception of the urethro-vagina and the prostatico-cervix of the uterus. Here we have noted the fusion of the two systems into a single system where male and female are combined.
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Such a finding as this substantiates the old theory of Waldeyer that there is a bi.sexual anlage of the genital ridge. We cannot quit« .SCO how Benda's theory, "that the primary anlage of the entire .sexual .system of the vertebrates must be regarded as female," would hannonize with facts now recorded. A separate devclo|)ment would .seem to be further substantiated by the fact that in every case of hermaphroditism on record there is always a .sharp tlistinction between the two kinds of tissue, and never an undifTerentiated mixture of botli elements, as would be the ca.se if the germinal epithelium could produce either male or female reproductive tissue.
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In ever}' male subject the prostatic utriculus, a homologue of the vagina of the female, can be demonstrated. It would appear from what we know of the embry^ological development of the urogenital system that there would be a fusion of the prostate, vagina, and uterus in an hennaphroditismus verus. This would no doubt explain the variation or fusions of the two systems found in the cadaver we are considering.
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HERMAPHRODITISM IN MAN 61
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LITERATURE CITED
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Benda, C. 1895 Hermaphroditismus unci Missbildungcn mit Verwischung
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(los Gesphlechtscharakters. Ergebn. d. allg. Path., Bd. 2, S. 627. C'oHUY, H. 1905 Removal of a tumor from a hcrmaplirodite. Brit. Med. J.,
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vol. 2. GvDERN.^T.scH, J. T. 1911 Hermaphroditismus verus in man. .\ni. Jour.
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Anat., vol. 11, pp. 267-78. H.\LB.\N, J. 1903 Die Entstehungder Geschlechtscharaktere. Arch. f. Gvnaek.,
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Bd. 70, S. 205. IIiRSCHFELD, M. 1905 Ein seltener Fall von Hermaphroditismus. Monats.schr.
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f. Harnkr. und sex. Hyg., Bd. 2, S. 202. Janosik, J. 18S7 Bemerkungen liber die Entwicklung des Genitalsj'stems.
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Sitzungsber. Akad. Wiss. Wien, Bd. 99, 3. Abt., S. 260. Ldksh, F. 1900 i'ber einen neuen Fall vom weit entwickeltem Hermaphroditismus spurius masculinus internus. Ztschr. f. Hellk., .\bt. f. Path.,
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Bd. 21,8.215. Meixner, K. 1905 Zur Frage des Hermaphroditismus verus. Ztschr. f.
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Heilk., Abt. f. prakt. Anat., Bd. 26, S. 318. NBUGEBAtJER, E. 1908 Hermaphroditismus beim Menschcn. Leipzig. PiiiLiPPS, J. 1887 Four cases of spurious hermaphroditism in one family.
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Trans. Obst. Soc. London, vol. 28, p. 158. Reizenstein, A. 1905 Uber pseudohermaphroditismus masculinus. Mlinchn.
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med. Woch., Bd. 52, S. 1517. Salix, E. 1899 Ein Fall von Hermaphroditismus verus miilatcralis beim
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Menschen. Verb. Deutsch. Path. Ges., Bd. 2, S. 241. ScHECKELE, G. 1906 Adenoma tubulare ovarie (testiculare). Hegar's Beitr.
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z. Geburtsh. u. Gynack., Bd. 11, S. 263. Si.MON', W. Hermaphroditismus verus. Virchow's Arch. f. path. .\n., Bd. 172,
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S. 1. TouRNEiTX, F. 1904 Hermaphroditisme de la glande genitale chex la taupe
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femelle adulte et localisation des cellules interstitielles dans le segment
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spermatique. (,'omp. rend, de I'assoc. des. anat., Toulouse, p. 49. Unger, E. 1905 Beitriige zur Lehre vom Hermaphroditismus. BerL klin.
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Woch.,Bd. 42, S. 499. Waldeyer, W. 1870 Eierstock und Ei. Leipzig.
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KXl'LAXATION (»!■ I'LATKS
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All the figures !»ro untoiiohiMl pliotoffaplis cif the organs (lesoribcd in this paper. Figures 1 and 2 are niacroseopie photographs of the external and internal genital systems. The remainder of the figures are microscopic iihotographs.
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l'I,.\Tl'; 1
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EXI'LAX.^TION OF KHiUnKS
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1 .\ photogra|>h to show the external genital organs. The short penis has Ix'eii dissected out with its crura and laid upon the jiuhis. The dilated urethra has l)ecn split and pinned open to show the small opening into the vagina as it turns liackward to enlor the uterus.
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2 .\ i)hotograpli of the same section from a pelvic view. The vagina and uterus have heen laid open and |iiniied backward to the l>road ligament. The ductus deferens can lie seen on the right side near the upper extremity as it enters the cervix of the uterus. Near the lower extremitj' of the uterus can lie seen both oviducts coming off from the angle of the uterus. The bladder could not be shown in the photograph.
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',i A microscopic sectitm to show the lumen and nmscular wall of a portion of the uterus. This was taken from the right side 2 cm. from the cornu.
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62
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I1I;k\1 MMIIiODITISM IN MAN
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111 IIKUT SlIKI'l'ARD
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ri.ATK 1
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63
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I'LATE 2
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F.XI'LANATION OF FIGURES
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4 A section of I lie ductus deferens to show the tunics. Considerable disintegnition 1ms taken place in the lumen. However, all the layers of the duet show clearly in the |)hoto);ra|)h.
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■) A section of the ovary. .\ large follicle is seen near the top of the photograph. T«o smaller follicles to the right can also be seen. Helow and near the
 +
bottom of the photograph is a light area. This was an area of disintegrated corpus luteuni.
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6 .\ .section of the oviduct taken about half-way between the ovary and the uterus.
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7 A low-]iowcr section of the testicle, to show the convoluted tul)ules and the connective tissue among the tubules.
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M
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HEHMAPHRODITISM IN MAX
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HfUUllT SHEPPAIU)
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PLATE 2
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IF
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'■-\<
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65
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ROOK REVIEW
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Le Emopatie. By Prof. Dott. Adolfo Forrata dclla H. Univorsita di Napoli. Vol. 1. Parte Generale, XVI and 1-482 pp., 21 colored lithographed plates and 8 text-figure.s. Milano: Societa Editrice Libraria, 1918. Price, unbound, L.30.00.
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This is one of the most interesting, complete, and usable books on morphological hematology ever published. It is the kind of book which unfortunately cannot be produced in this country, for no American publisher covikl furnish the splendid colored lithographed plates and probably no pulilisher in this country would publish such an extensive text on a subject which necessarily a]ipeals to a small audience. The plates are of exceptionally high quality, and the figures are so arranged that the plates will prove verj^ useful even for those who have difficulty with the Italian text.
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The text matter is arranged very systematically, and each chapter is followed by a very extensive bibliography. Citations to literature and discussions of theories are so numerous that the l)ook will be of great value as a reference work to anyon(> working in this field. It should be accessible to every laboratory in which there is an interest in hematology.
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The book is far more than a compilation of the work of others, for there is a hardly a phase of the subject to which the author has not contributed by his own researches, the results of which have appeared in numerous previous publications. The work is really an extended resume of Ferrata's own work and that of his students aTid collaborators, Di Ciugliehno anil Negreiros-Rinaldi. Of special value is the fact that it has been possilile to include the results of most recent research in this field. It is thus the only ])lace where oiu^ will find a suiiunarv of nuich of this work.
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The chapter on technique, to which the first eighty-four pages are devoted, gives a very complete account of the modern methods of counting, haemoglobin estimation, fixation and staining of blood smears and of the blood-forming organs, with consideral)lc space devoted to the methods of supravital staining of fresli blood and the making of permaninit preparations of blood smears stained in this maimer.
 +
 +
Part II, sixty-three jiages and eleven jilates, deals witli the red blood-cells. The results of supravital staining, the maturation of the red corpuscle, and the pathological m()r])ho]ogy of erythrocytes, including polychromatophilia, basophilic punctation, Howell-JoUy liodies, etc., are promincnl f(>atures of this section. Sixteen pages arc devoted
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07
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tiS LE EMOPATIE
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to till- discussion of hiisopliilic piinctation. In ri'nanl to tlio orinin of the l)a.sopliilif uriiiiulcs it is to hv nott'(l that Forrata has fcivcn up his foruKT view that tlioy arc derived from tlie paracliioiiiatin of the miclcus. Willi Pappeiiiieim and Askauazy lie now ajirees that they are of cytoplasmic origin. Mis ^I'lx'i'id conclusion in re^rard to basophilic granulation is that it represents a i)hase of maturatioti of normal erythrocytes in ceitain |)eriods of emhryonic life: it is alvpical for the adult, and morpholonically it corres])on(ls to the l)aso|)hilic suhstancc of the primitive lymphoid erythrohlast. In the normal adult the erytiirocyte passes through a polychromato|)hilic i)hase in order to reach its final acidophilic state, hut in pathologic conditions of the adult 'conclohation'of the basophilic substance during the polychromatophilic stane ^ivcs origin to the basophilic granules. Clinically, basophilic crannies appeariiii; in more or less severe types of anemia indicate a return of the mechanism of maturation of the erythrocyte to an embryonic type. In this connection it must be remembered that Ferrata's previous researches havr- shown that a condition analogous to ba.sophilic punctation is a normal jihase dining the maturation of the erythrocytes of early mammalian embryos.
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Several plates arc devoted to illustration of the maturation of the erythrocyte and megalocyte. The numerous exceptionally clear figures include all import. ant stages in the dilTerentiation of red cells from the 'hemocytoblast' (jirimitive progenitor of all the granular leucocytes and erythrocytes) to the fully matured non-nucleated orthochromatic erythrocyte. Ferrata and Negreiros-Kinaldi have been successful in recognizing the very earliest stages in the dilTerentiation of the red-cell series in a cell-type which they have named 'proerythroblast.' This cell retains the nucleoli of the 'hemocytobla.st' ('lymphoidocyte' of Pappenheim), but shows some slight differences in other res[M'cts. The chromatin network is .somewhat coarser and the light spaces l)etween the chromatin strands are more sharply defined. The cytoplasm is more homogeneous and more basophilic and does not show the spongy ditTcreiitialion of the primitive stem-cell. This cell is inserted between the lyin|>hoid hemoblast of Pappcnhcim and th(^ stem-cell. I'or the nicgaloblast a similar stages is iccognized — the promegaloblast.
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Part III, j)ages lti7 to 212, plates XI to X\'I, deals with the leucocytes. In the evolution of the neutrophil leucocyte Ferrata distinguishes between the 'proneutrophilic myelobla.st' and the 'neutrophilic jiromyelocyte.' Isxcepting for tin- jiresence of fine azin-o|)hiiic granules in a basophilic cytoplasm, the former resembles the hemocytoblast in structme. In the neutrophilic promyelocyte the fine azm-ophilic granules are gi'aduall>' replaced by neutrophil gramiles lying in an oxyphilic cytoplasm and the nucleus giadually assiunes the coarser structure which is characteristic of the myelocyte. The ])roeosinophilic myelobla.st contains very coarse azurophil granules and tlie eosinophilic promyelocyte eosinophil granules in addition. It should be jjointed out here that most authors do not agree with FerrataV assumption of
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BOOK REVIEW 69
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relationship between the character of the azurophil granulation and the further differentiation of the myeloblast, although it is generally conceded that the azurophil granulation of 'myeloid' cells differs from that of lymphocytes.
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Part IV, forty-four pages and one plate, deals with the blood-platelets. Naturally a large portion of this chapter is devoted to the various theories on the origin of blood-platelets and to discussion of the extensive literature on the subject. The discussion is unusually complete for a book of this kind.
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Ferrata derives blood-platelets from megakaryoc}i:es, as originallj^ discovered by Wright, and also from 'monocytoid' cells having azurophil granules arranged in small groups as in blood-platelets. These latter cells are found especiall.y in the bone-marrow of the embryo.
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Part V, pages 31.3 to 399, dealing with the hematopoietic tissues, is the most interesting and original section of the book. Due consideration of the connective tissue as a diffuse hematopoietic tissue is a decided and much-needed innovation. The 'hemohistioblast' (resting wandering cell of Maximow, clasmatocyte of Ranvier) of the connective tissue and the 'hemocytoblast' comprise a uniform anatomical system, identical in embryological origin and differential potentialities; they form the hematopoietic parenchyme in the widest sense of the word.
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The specific hematopoietic tissues of the bone-marrow, lymph nodes, and spleen are discussed first, this portion of the chapter being altogether too brief in proportion to the space devoted to the diffuse hematopoietic tissue. The hemocytoblast, similar in structure to Pappenheim's lymphoidocyte, is the progenitor of all the bone-marrow cells, and a similar cell in 'lymphoblastic function' gives rise to the lymphocytes of lymph nodes and spleen. The monophyletic theory is, therefore, accepted by Ferrata, but not the extreme unitarianism of Weidenreich and Maximow, for Ferrata believes in functional dualism to the extent that fully differentiated lymphocytes are incapable of differentiating into granulocytes or erythrocytes. In the spleen pulp the myeloid function of the hemocytoblast is retained to a certain extent, which explains the limited production of myeloid cells in the pulp of the normal adult.
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The section devoted to the 'hemohistioblastic,' or 'diffuse hematopoietic' (connective) tissue is of special interest. The colloidal dyes (Trypanblau, Pyrrholblau, Lithiumcarmine) are made use of for the purpose of determining the relationships of the cells of this tissue. The jirimitive cell of this tissue is the resting wandering cell (^Maximow) derived from an amoeboitl emliryonic mesenchyme cell and giving rise to all the other tyj^es of cells of the connective tissue. These are divided into chromophobe (without dye granules) and chromophile (with dye granules) types. The latter include the resting wandering cells, fat cells, endothelial cells, and filiroblasts. The fibroblasts, on account of the character of their dye granules, are regarded as highly differentiated cells, while fat cells and endothelial cells are considered to be functional adaptations of the hemohistioblast (resting wandering cell). The chromophobe cells include jilasma cells, mast cells, eosino
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70 LE EMOPATIE
 +
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phils, and lyiiipliocytos, and tlipy arc also clitTcirntiated from the henioliistiohlast wliicli lost's its capacity for storing colloidal dyes during tluMr diffcri-ntiation.
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In tlic opinion of the reviewer, much remains to be proved before this classification of Ferrata's can l>e adopted. The whole structure is built up on the assumption that the reaction of the cells to the colloidal dyes is specific. Recent work of the reviewer' seems to indicate that the reaction is not specific, but that the behavior of cells toward colloidal dyes depends entirely on functional and environmental conditions, in other words, the presence or absence of dye granules is not sufficient to enable us to distinguish between hemohistioblasts and lymphocytes, or between monocytes of the tissues and large mononuclears of the blood.
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Serious objection may also be offered to the view that the 'hemohistioblasf is always a more i)runitivc cell than the lymphocyte, and that the lymphocyte i of normal circulating blood) is a difTercntiated mature cell incapable of being transformed to a granulocyte and incapable of reverting to a hemohistioblastic resting wandering cell. In this connection it is sufficient to refer to the recent work of Weill, '^ who has shown conclusively that lymphoc>'tes, even those having the structure of small lymphocytes, are capable of differentiation into granuloc>-tes. It is true that these obser\-ations were made on human and manmialian thymus, spleen, and nmcosa of digestive tract, but until real or even functional differences between lymphocytes of the blood and those of the tissues have been demonstrated, they must be regarded as valid objections to Ferrata's theory.
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Numerous objections to FVrrata's view of the relationship between resting wandering cells and lymphocytes could be offered, but this is not the place for the lengthy discussion which would be necessary. Many of these topics are considered again in the following section, where the literature is given due considcTation.
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Fart \l, pages 400 to Kit), deals with the morphogenesis of the cells of the blood. The first part of the section is concerned with the genesis of the blood-cells of th(> embryo. \'arious theories are considered, but emphasis is i)laced on the results of the author's own researches. Although space will not permit discussion of this chapter, the reviewer wishes to call special attention to Ferrata's own conclusions in regard to the relationship of the blood-cells. The first basophilic lymphoid blood-cells derived from the mesenchyme of the early embryo are not lymphocytes, but a special type of 'primitive transitory hemocj'to ' Dow.vKY, Hal 1917 Reactions of blood- and tissue-cells to acid colloidal dyes undfT experimental condition.s. Anat. liec, vol. 12.
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191K Further studies on the reactions of blood- and tissue-cells to acid colloidal dyes. .Vnat. lire, vol. 15.
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' Weill. P. 1919 I'oIkt die Mildung von granulierten Leukozytcn im KarzinomKcwcbe. Virchows .Arcliiv. H<l. TM. Heft '2.
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1919 I'rbcr die lourorvtiiren Elemcnte der Darmschleimhnut der Siiugctiere. Arch. f. nukr. .\nat.. M.'m. U-'t 1.
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1919 I'etwr dii-s reKclinJuwigc Vorkominen von Myelocytcii in der Milz dcs envachsrnen Mcn.-tchen. Arch. f. niikr. Annt., Bd. 'Xi. Heft 1.
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BOOK REVIEW 71
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))lasts' wliifh are all under ei ythro])la.stie function. P^or a time they all differentiate into promegaloblasts, megaloblasts, and megalocytes, the primitive red-cell generation of the early embryo. In the second phase, that of the hematopoietic activity of the liver, the mesenchyme cell (hemohistioblast) differentiates into a new type of primitive cell, the definitive hemocytoblast in myeloid function which in turn differentiates into erythrocytes, granulocytes, and megakaryocytes. This second hemocytoblast corresponds morphologically to the 'myeloblast' or stem-cell of the adult. In the third (fetal) phase, during which the lymphoid tissue appears, the mcsenchymatous hemohistioblast gives rise to a hemocytoblast of lymphoid function which produces lymphocytes, although it is morphologically identical with the myeloid hemocytoblast. The different end-jiroducts are due to temporary functional differences only.
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According to this scheme all the lilood-cells are traced back to the fixed tissue cell, the hemohistioblast, the cell which stores colloidal dyes in the connective tissue of the adult. In the early embryo this cell differentiates into the primitive transitory hemocyi:oblast, and this in turn to the primitive red cells of the embrj'o (megalocj-tes), while in the adult, lymphoid and myeloid hemocytoblasts (functional differences only!) and monocytes are the products of its differentiation. The monocytes may also be derived from both the lymphoid and myeloid hemocytoblasts.
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This scheme seems to harmonize the actual observed facts with both the unitarian and dualistic theories better than any other scheme which has been presented. A good part of this section of the book is devoted to discussion of the unitarian and dualistic theories and the last fifteen pages to the doctrine of Fcrrata.
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In part ^TI, pages 469 to 482, the author discusses the morphological significance of the cells of the blood and the hematological formula. The discussion of the .significance of azurophil granulation is of special interest. Ferrata takes the stand that the presence of azurophil granulation in a myeloblastic lymphoid cell indicates beginning differentiation toward a granulocyte, which may be either an eosinophil or neutrophil granulocyte, according to the character of the azui'e granules. The azure granules are not transformed into the specific granules of the leucocytes, but are replaced by the latter. The presence of azurophil granulation in myeloid cells, therefore, indicates maturity and beginning differentiation and is of greater significance than the mere temporar\' secretory activity assumed by Pappenheim.
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The reviewer has picked out only a few of the interesting and significant parts of the liook for special mention. In closing he wishes to state that the book constitutes one of the most important recent additions to hematological literature. The statement on the title page that it is a "Trattato per mcdici e studenti" is somewhat misleading, for it is more than an ordinarj- text-book.
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Hal Downey, University of Minnesota.
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'\'
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THE ANATOMICAL RECORD, VOL. 19, NO. 2
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Resumen por el autor, J. A. Pirer? De Lima, Instituto de Anatomla
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de la Facultad de Mcdirina,
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Oporto, Portugal.
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Estudio de un feto clclope de cabra, macho, procedente de Nova Goa (India Portuguesa).
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El feto estudiado tenia un solo globo ocular con dos c6rneas y tre.s pdrjiados, uno superior y dos inferiores. Ausencia complota de aparato nasal; labio superior terminado en punta roma y niandfbula prognata y recurvada hacia arriba. Cerebro chato y cninco en gran parte lleno de un liquido seroso que se veia por transparencia a trav(!s del frontal. .Vusencia de nervios olfativos y oculo-motores externos: un solo nervio 6ptico. Un solo frontal, dos parietales, dos inter-parietales, un solo maxilar y, por encima de 6\ un hueso al cual llama el autor interzigomdtico. Una sola 6rbita. Agenesia del etmoides, de los cornetes, intermaxilares, palatinos, lacrimales, nasales y v6mer. Tres de los incisivos ya en franca erupci6n. Se trata de un ciclocefaliano cicloc6falo, segun la clasificaci6n de G. Saint Hilaire, y de un Cyclops arrhynchus segun la nomendatura de Gurlt. 8e compara este caso con otros descritos por el mismo autor y por diversos teratologistas.
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TransUtion by Joa^ F. Nonida Cornell Vni^-enity Medical Collc«c, N. Y.
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author's abstract of this paper issued
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BT the BIBLIOORAPHIC SERVICE, MAT 24
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ANATOMY OF A FETUS OF A CYCLOPEAN GOAT
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J. A. PIRES DE LIMA Institute of Anatomy of the Faculty of Medicine of Oporto (Portugal)
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SIX FIGURES
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Prof. Froilano de Melo, of the School of Aledicine and Surgery of Nova Goa (Portuguese India), sent me for study a monstrous fetus of a goat. It was received by the Museum on the 4th of January, 1919, immersed in alcohol.
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The skin was covered with white hair, except at the upper part of the head, where there was an extensive areaof black hair, stretching forward and encircling the eyelids, as well as the lips; besides, some small disseminated black spots. At the top of the head there were noticed three vortices of hair arranged in the form of a triangle.
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The fetus was of the male sex, and kept the umbilical stump of the cord. Only the head was abnormal. On external inspection (fig. 1), the presence of a single median eye was noted, under which there was found a deep depression corresponding to the nasal apparatus, which was completely missing. The tongue protruded from the mouth and inclined to the left. Above it, in the median line, one noted the upper lip ending in a blunt point, and underneath, a voluminous mandible, prognatic and turned up.
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The ocular globe of this monster was possessed of two corneae separated by a narrow light median zone. It was surrounded with three eyelids, an upper one with a free and convex border and two lower eyelids convex free at the borders and united in the median line. Only one conjunctiva connected the ocular globe to the deep faces of the three eyelids, in its reflexion forming conjunctival culs-de-sac, superior, inferior, and lateral, right and left. The palpebral cleft was 2 cm. wide and 1 cm. high.
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73
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74 J. A. PIRES DE LIMA
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Close to the corners of the eye there were found long lashes, and on the right one there were observed long hairs inserted above and below the eyelids. In the depression existing between the eye and the mouth, on the wrinkled skin, two vortices of hair on the median line were to be seen and two tufts of hair (tentacles) crowned the anterior part of the lips.
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The head was flattened transversely. The following measurements were obtained:
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im.
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Maximum anteroposterior diameter 5
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Maximum t ransverse diameter 4
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Distance from the nape to the symphysis of the mentum 7.3
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Length of e.ich car 5
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The cephalic index 80.'
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The remainder of the fetus presented the following measurements:
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cm.
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Circumference of the neck 9
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Length from the nape to the basis of the tail 25
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Length of the tail 4
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Perimeter behind the implantation of the thoracic members 22
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This specimen did not possess behind the mandible the pyrifonn appendices called in Portuguese brincos (ear-rings), commonly seen in goats, representing an auditory appendage of the second branchial cleft.' After having studied the external morphology, the osseous skeleton was exposed. The upper surface of the skull (fig. 2) presents the form of a lozenge, to the angles of which the frontal, parietal, and occipital bones, respectively, correspond. '1 he cranial vault i)rese;itcd a .smooth surface, comprising the following bones: frontal {F} single; parietal (P, P) separated by the sutura interparietalis; squama occipitalis (iu> notices ii) it from hofore to behiiul: the single optic nerve, on tlie median line, penctratinfj an optic foramen (//) as wide as tlic occipital one; a nerve (///, I\'}, which must represent the coimnon ocnlomotorius antl the pathetic nerve, distinct before the dura mater hail been withdrawn; the n. trigeminus {V): the facial and auditoiy nerves {VII, VII I), and last all the following ones (/.V- . . .) '" 1^ single fascicle. The hypoglossal nerve, which ai)peared well detached before the removal of the dura mater was not to be seen afterward.
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'I'he ocular globe was large, oval with a single optic nerve and a single cavity. Only the cornea .showed signs of duplicity in the forcjiart. On o|)ening the ocular globe, this was found so macerated as to make it unsuitable for stud}'.
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Contrary lo what is generally the case, in this specimen,^ wiiich I sui)pose to be a deail-liorn fetus, three of the incisor teeth had already appeared ; t lie piiicer, the first right mitoyenne, single, as well as the fir.st left mitoyenne, this being considerably developed. The left pincer and the secontl mitoyennes were beginning to appear.
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The dissection of the neck tind the autopsy of the thorax and of the abdomen did not reveal any abnormal disposition worth registering.
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According to the clas.sification of I. (ieoffroy Saint-Hilaire,' this monster belongs to the class of the Cyclocei)haleans; that is to say, to the class of monsters having the nasal ai)])aratus more or less completely atrophied, the ajiparatus of vision imperfectly formed, sometimes quite rudimentary, directed to the median line and almost always united.
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It still bch)ngs to the 'C'yclocephalus' genus, to the cycloccphaleans having a single orbital cavity, two contiguous eyes or a double eye occupj'ing the median line, the nasal apparatus atrophied ;uid no j)roboscis.
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• ('himvcuii iind .XrloiiiK (Inc. cit.) .iny that the pincers apiu-iir from tlic third til the fifth ilay, iis well a.s llic fir.Kt initoycniie. Tlic second niitoj-enncs would make (heir appearance about llie tenth day after birth.
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' I. (leoffrey Saint-liihiiru Ilistoire GC-nfraic et partieiiliero des anomalies d'orKanisalion eliez I'llonimc et les animaux, I'uri.s, ls:jG.
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ANATOMY OF A FETUS OF A CYCLOPEAN GOAT
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79
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According to Gurlt's classification, my specimen should be classified as a 'Cyclops anynchus.'
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Besides this cyclops. I have already had an opportunity to study three in the human species.' A fetus 9 Cyclocephalean rhynocephalus, having an ocular globe adherent to the eyelids (1 sujjerior and 2 inferior) without conjunctival culs-de-sac, either superior or inferior. The ocular globe, shapeless, seemed to be formed by two eyes which had fused into one. There were two frontal bones with sutura metopica.
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K-Xl
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r f^ff
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/ -V
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V
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6
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ihe second case was a Cyclocephalean cyclocephalus cf. A superior eyelid and an inferior one, formed, by two soldered palpebrae. Ocular globe atropliied and deformed. Frontal single. Genu varum.
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The third case was a skull of a fetus with a median orbit, a single optic foramen, frontal single, very salient frontal and parietal protuberances.
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' 'rurudi-Slciri:! ilclhi Toratolofjia. T. (1. Bologna, 1891.
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' J. A. Pires de Lima. Sobrc Ires inoiistros ciclocefalianos (Anais Scientfficos da Faculdade de Medicina do Porto, vol. 4, no. 2).
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80 J. A. riRES DE LIMA
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III an Otocophak'un pi^ v which 1 stiulietl,* the frontal and parietal hones were rcclucctl to a sin{?lc piece, forming the cranial vault.
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An Oimilymus cat cf. wliicii 1 doscril)e(l,' had a concentric ()rl)it with a double eye, apparently rather similar to the single ocular globe of the present observation. However, it has two optic nerves, besides two corneae.
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According to Cieoffroy Saint-llilaire,'" the C'yclocephalean rhinocephali, as in the present observation, mostly have too small an encephalon to fill the cranial cavity; there exists then almost always a larger or smaller (juantity of fluid,
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In ISOO, (lintrac" studied a human fetus 9 born at term, Cyclocephalean rhinocephalus. Its skull was much reduced. The median eye had two corneae and the hind jiart of the skull a sac full with a lemon-yellow fluid. The brain was atrophied. The olfactory nerve was missing; perhaps also the patheticus, the oj)tic nerves were in close proximity.
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Tarufli'- also mentions the presence of a remarkable quantity of li(iuid within the skull of the cyclojjs. The same author records that in these monsters the olfactory nerves are always missing and that there is a single optic nerve with the chiasma absent.
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Tarufli, moreover, states that the cyclopia is much more common in the female sex.
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I'hisalix" has studied four monsters cyclocephalean or otocephalean, one in dog, two in sheej), and a human fetus; in the last, attention wa.s nnmediately drawn by the absence of cerebral hemispheres normally constituted; the skull once openetl, there came out a serous, light, opaline liquid, lodged in a sac, at the
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' J. A. PircH (Ic Lima, fitiido diiii iii(>[istrc otoct-phalicn (Bulletin de la Soci(St6 l*iirtiiKui«<> <k'9 Sciences Natiirelles, T. .S).
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• J. A. Pircs dc Lima, Study of an opodymua kitten (Journal of Anatomy, vol. .V.').
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'• I. G. Saint-llilaire, loc. cit.
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" (linlrac, ('onsiderations sur la cycl<)c<phalie (Actos de I'.Vcaddmie Imp6riale de Sciences, Belles lettres et Arts, Bordeaux, 1800).
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"Taniffi, loc. cit., T. 8, Bologna, 1804.
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" Phisalix, Monstres Cyclopes (Journal de rAnatomic ct de la Physiologie, Paris, 18.89).
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ANATOMY OF A FETUS OF A CYCLOPEAN GOAT 81
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bottom of which was the ciicephalon. Instead of brain, one noted a whitish and flattened mass. In this specimen nerves of the I and IV pair were wanting.
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Rabaud," in an extensive memoir, has discussed fifty abnormal chicken embryos, concluding, in accordance with Dareste's opinion, that the cyclocephalia is due to a developmental disturbance of the encephalon.
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Watkyn-Thomas'^ has described a human fetus 9 with incipient cyclopia; it had two eyes drawn nearer and a single nasal orifice, without olfactory ner\-es. In the Museum of the Anatomical Institute I have stored a similar monster, which I will presently study.
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Lately in America several works dealing with cyclopia have been published. I shall mention the following:
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Stockard"' has made some interesting experiments on teratogeny of fishes, artificially obtaining cyclopean monsters by means of solutions of JMgCb or Mg(N03)2 and he believes it may be concluded that such monstrosities in man and other mannnals are due to an excess of magnesivun salts in the maternal blood or in the amniotic fluid.
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Warren Lewis has likewise published experimental observations on teratogen}^ of fish embryos.
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Whitehead' 8 has studied a human fetus cj^clocephalus.
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Chidester has described a cyclopean rat, an atocephalean pig, as well as the brain of a human fetus cyclocephalean. The same author^" has studied some double monstrosities in fishes, one of them complicated with cyclopia.
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Finally, Werber^' has also occupied himself with experimental teratology and specially with teratophthalmia.
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"Riibaud — Recherches embryologiques sur les cyclocephaliens (idem, 1901-02).
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'* \Vatk}-n, Thomas, A cyclopean foetus with hernia encephali (Journal of Anatomy and Physiology, vol. M).
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'* Charles Stockard, The artificial production of one-eyed monsters and other defects, which occur in nature, by use of chemicals (Anat. Rec, vol. 3).
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" Warren Lewis, The experimental production of cyclopia in the fish embryo (Fundulus heteroclitus) (idem). "Whitehead. A case of cyclopia (idem).
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" Cliidcstor. Cyclopia in mammals (Tlie Anatomical Record, vol. S).
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"' Idem. Twins in fish, one with cyclopean deformity (idem).
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-' Werber, Experimental studies aiming at the control of defective and monstrous development (idem, vol. 9).
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ResunicM p<>r el autnr, O. 1'. Kainpnioior, EsdU'hi (if Mc'diciiKi Marquette.
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Los canihios en el plan sistemico vciutso durante el ilesarrollo y
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la relaci6n do los oorazones linfatioos de los
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anuros con estos canibios.
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I)es|)uesde iiulicar l>rovoiii('iit(' los trabajos de Ooette y Hochstetter sohre el desarroUo del sistenia venoso on los anfihios, el autor dcs(Til)e la forniaci6n do las venas sistrniicas ei\ Bufo. Mc'diantees(iueniasdciuuestra(|ue exist e una correspoiidencia mas estreeha en la disposicl6n priuiaiia y <ainbios de estas venas en los vertebrados inferiores y superiores, (jue lo que se ha supuesto. Por ejeniplo, el componente subcardinal del sistema venoso existe ya en los estados j6\ones de einbriones de anuros. El autor denuiestra tan)l)ien conio se i)roducen las diferencias, aparentem(Mit(> irrecoiu'ilial)l(>s, entre la situaciAn do las oonuuiioaciones linfatico-venosas del cnibn6n y las de los individuos coniplctaniente desarroUados. En el anfibio anuro adulto, por ejemplo, los corazones linfatioos antoriores desembocan en la corresponilionte vena vertebral anterior, que a su vez es trigutaria mas antoriormonte do la vena yugular interna. En en embriAn, por otra parte, el coraz6n linfatico anterior, que se origina a expensas de la vena de la linoa lateral que pasa a este nivel, oomunioa con el seno venoso i)r(jnefr6tico, cjuc reprcsenta la confluencia de las venas pre- y postcardinales alredodor del i>ronefros. De un niodo semejante, los corazones linfatieos posteriores se originan a lo largo do las vonas do la linoa lateral, poro on el adulto vionon a punorso en rolaoiAn eon las vonas is(|uiaticas ])or iutoriModio lie las vonas vertebrales posteriores. Los esquemas demuestran adonuis con (pio faoilidad las variaoionos tan connmes .se producen i)or la ex|)an.si6n. roducci^n o persistoncia dc diferentcs .■^oginentos de las venas intersegniontarias originariamente sinietricas. cuyas variaciones dan lugar a diferentes relacioncs con los troncos veno.sos principales.
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Tranalntion by J<m^ V. Nonicirs Comrll I'nivpraity Medical Collrsr, N. V.
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aitthor's ad&tbact of this paper issued by the bibliographic service, may 24
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THE CHANGES OF THE SYSTEMIC VENOUS PLAN DURING DEVELOPMENT AND THE RELATION OF THE LYMPH HEARTS TO THEM IN ANURA^
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OTTO F. KAMPMEIER
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Department of Anatomy, Marquette School of Medicine, Milwaukee, Wisconsin
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NINE FIGURES
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Our knowledge of the primary venous plan of anuran embryos and its subsequent transformation is based almost wholly on the observations of Goette and Hochstetter.^ In his classic work, " Entwicklungsgeschichte der Unke" (1875), Goette gives a clear account of the development of the systemic veins of Bombinator. In some respects, however, the venous system of Bombinator differs from that of the more typical Anura, the most marked difference being the persistence normally of the anterior portions of the postcardinal veins, for which the term 'venae azygae' has generally been employed in the literature. In the retention of the postcardinals alongside of a postcava, Bombinator closely resembles the urodeles, the salamander, for example. Hochstetter ("Beitrage zur vergleichenden Anatomic und Entwicklungs ' This paper represents a section of a larger paper on the origin and development of the lymphatic system in Anura which was originally intended for publication in a monograph, as indicated in The Anatomical Record, vol. 16, August, 1919. Adequate funds were not available to publish that work as such, and it was decided to split it into several parts and have them appear as separate papers in two or three of the anatomical and morphological journals. Though, in a sense, the unity of the work is thereby destroyed, the disadvantage is offset by the advantage of its wider circulation.
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' For a comprehensive list of the literature on various aspects of the venous system of the .Vnura, I refer to the following works: "Beitrage zur vergleichenden Anatomie und Entwicklungsgeschichte des Vcnensystems der Amphibien und Fische," by Hochstetter in Morphol. Jahrbuch, 1S8S; ".\natomic des Frosches," by Ecker and Wiederscheim, 1896 (Oaupp's revision); 'Vergleiehende Anatomie der Wirbeltiere," (7th ed., 1909), by Wiederscheim.
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83
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84 OTTO F. KAMPMEIER
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posrhichto dos Venensysteins der Ain])hil)icn und Fische," Morphol. Jahrburh, 1888) has indicated wherein the differentiation of the cardinal system of veins in the frog varies from that in Bonihinator.
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Since the time of Goette's and Hochstetter's work, no systematic study, so far as the writer is aware, has dealt with the above problem in the light of the more recent work on other vertebrates, nor have the changing relations of the larger venous branches to the main trunks during development been considered. The following diagrams and brief description show that a closer correspondence exists between the lower and the higher vertebrates in the genetic history of their venous systems than has been supposed.
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A matter of greater importance in the writer's opinion, is the fact that no account has demonstrated how the seemingly irreconcilable differences between the situations of the lymphaticovenous communications of the embryo and those of fully formed individuals are brought about. This process has interested the writer greatly not only in his investigation of the lymphatic system of Anura, but also in his effort to furnish a systematic presentation of the comparative morphology of the systemic lymphatics in vertebrates.^ It is a well-established fact that in the adult anuran unii)hibian the anterior lymi)h hearts discharge into the corresponding anterior vertebral vein, which further cephalad is a tributary' of the internal jugular vein. In the embn,'o, on the other hand, the anterior lymph heart, arising on the transient vein of the lateral line, comnumicates with the pronephric venous sinus, which represents the confluence of the preand postcardinal veins around the pronephros and is continued to the sinus \enosus as the duct of Cuvier. Similarly, the posterior Ijanph hearts arise along the lateral-line veins, but in the mature form come in relation to the ischiadic veins through the posterior vertebral veins. In comparing the anterior hnnphatic taps of an adult anuran with those of a manunal, for example, one would hardly conclude that they are identical, and yet, when their embryonic history is revealed, both can be definitely re • This work is in process of preparation.
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DEVELOPMENT, SYSTEMIC VENOUS PLAN, ANUKA 85
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ferred to the cardino-Cuvierian district, where such communications occur with remarkable constancy either temporarily or permanently throughout the entire series of vertebrates, from the lowest to the highest. In the same way, the posterior lymph hearts can be compared with certain members of the lateral series of mtersegmental lymph hearts in the tailed amphibians on the one hand and with the iliac and coccygeal lymph hearts of reptiles and birds on the other. Studies like these have impressed the writer, as other investigators have doubtlessly been impressed before, that biological homology becomes an exact science only when it rests squarely on the comparative anatomy of the embryo.
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The following account is based almost wholly on a study of the toad, Bufo. The younger embryonic stages belong to the European species, Bufo vulgaris, the later stages, including young individuals shortly after metamorphosis, to the American form, Bufo lentiginosus. Besides these, a few mature frogs, Rana pipiens, were examined. The inserted diagrams have been constructed from a series of graphic reconstructions of the venous system of progressively consecutive stages.
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Toad embryos (Bufo ^allgaris), 4 to 5 mm. long, possess the primary venous ground plan of vertebrate animals, namely, the simple symmetrical cardinal system, as illustrated in figure 1. There are a number of peculiarities, however, which should be emphasized, since they are directly or indirectly involved in the development of the lymph hearts and associated veins. At the junction of the precardinal (internal jugular) and postcardinal veins, a proportionately large venous sinus (si. proneph.) has been formed, a broad plexus of channels which encompass the tubules of the pronephros. Of greater interest are the mtersegmental veins {1-8 v. seg.),* a metameric series of vessels which pass vent rally between the myotomes and epidermis to empty
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It should be stated that since there is a possibility of the reduction of intersegmental veins at the extreme anterior end of the series during phylogenesis,
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just as the spinal ganglion I is an evanescent structure, the designation of the intersegmental veins by specific numerals must be taken with reserve when homologizing Bufo with other Amphibia.
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86 OTTO F. KAMPMEIER
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into the cardinal vein tnink, the first three into the pronephric sinus and the remainder into the postcardinal. But not all of them are present at the same time, for in their appearance, as with other events of cmbrj-ogenesis, the processes of developmeni proceed in an anterioposterior direction. WTien the foremost intersegmental veins have been established, the more caudal ones may still be lacking, and when these have been laid down and have attained importance, the anterior ones have already begim to disappear or become modified (figs. 1 to 4) ; only in the lower Amphiljia do the intersegmental veins persist as such during the entire life of the animal. Occasionally, too, there are slight irregularities in their arrangement, such as the convergence of two consecutive vessels to join the postcardinal at the same point. But these are insignificant fluctuations, and in the diagrams they have been disregarded.
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The original condition of the postcardinal, lying against the medial side of the primary excretory tube of Wolffian duct, is soon altered by the formation of a second channel on its lateral side as the result of longitudinal anastomoses between the intersegmental veins near their points of confluence with the postcardinal (figs. 2 and 3). At the same time, these two parallel channels, which for the time being maj'^ be considered as the medial and lateral divisions of the postcardinal {med. and lal. v. card, post.), become united by numerous transverse anastomoses which pass around, over, and under the Wolffian duct so that this structure becomes enclosed by a cylindrical venous plexus. Hochstetter states that the latter condition only obtains in the salamander, but the writer's material shows without doubt that such takes place normally in the larval Anura as well. At the posterior end of the trimk, the postcardinal vein fuses with its fellow of the opposite side and is prolonged into the tail as the caudal vein (v. cnitd.). Here, too, a paired vessel, the common rudiment of the proximal part of the abdominal and external iliac (v. iliac.) veins, branches off and passes laterally around the hind-gut to its under side where it extends forward a short distance.
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DEVELOPMENT. SYSTEMIC VENOUS PLAN, ANURA
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87
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acuv. I\
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sin.ven. vjuse
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^■, vcardant.
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1 _iO
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2 ^Wff
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j'nO
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i_ rCT
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f v.om.tnes.^ y
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^ mO
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-_ -1
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i al.proneph.^
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T20
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5. '
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k f
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tO>
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1 tZ"
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mO
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7 — 6.
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ft- post. X
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ai<3 ■ ■BHO
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xo
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no
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aiO mO
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Figure 1
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Figs. 1 to 4, diagrams of the systemic veins in 4-, 6-, 7-, and 10-mm. embryos of Bufo vulgaris, respectively; figs. 5 to 7, in 15- and 18-mm. tadpoles of Bufo lentiginosus, and a stage immediately before metamorphosis; fig. 8, in the young toad (B. lentiginosus) immediately after metamorphosis; fig. 9, in a mature frog, Rana pipiens. All figures (except 9), XSSj. As all the structures are shown in the diagrams as lying in the same plane, there is, of course, a certain degree of distortion; thus, the intersegmental veins appear to be lateral tributaries of the cardinal- veins when in reality they are dorsal ones.- The spinal ganglia, I, II, III, etc., were introduced to indicate levels.
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COT tym. ant., cor lymphaticum anterior cor lym. post., cor lymphaticum posterior d. Cuv.. ductus Cuvieri SI. proneph., sinus pronephros sin. ven., sinus venosus V. abdom., vena abdominalis V. brack., vena brachialis V. card, ant., vena cardinalis anterior V. card, post., vena cardinalis posterior {med. and lal.), medial and lateral divisions V. caud., vena caudalis V. cot), ant., vena cava anterior V. cav. post., vena cava posterior V. cut. fem. post., vena cutanea femoris
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posterior V. cut. mag., vena cutanea magna V. dors, lumb., vena dorso-lumbalis
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fern., vena femoraUs hep. rev., vena hepatica revehens iliac, vena iliaca
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iliac, trans., vena iliaca transversa ischiad., vena ischiadica Jacobs., vena Jacobsonfi ■ jug. exl., vena jugularis externa jug. int., vena jugularis interna Ja/., vena lateralis ,^,
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om. mes., vena omphalo-mesenterica (vitelline veins)
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ren. adv., vena renalis advehens seg. 1, S, 3, etc., venae intersegmentalis
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subcard., vena subcardinalis stibclav., vena subclavia vert, ant., vena vertebralis anterior vert, post., vena vertebralis posterior interanastomosis between the subcardinals
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THE AN*.\TOMIC.\L RECORD, VOL. 19, NO
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88
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OTTO F. KAMPMEIER
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Soon after, in 7-iiiin. embryos, the two divisions of the postcardinal begin to diverge from one another in the middle of their course (fig. 3) due to the crystallization, as it were, of the anlagen of the mesonephric tubules, which crowd between them. Consequently, the medial postcardinal components, which may now be termed the subcardinal Kins, since Ihey are unquestionably the homologucs of Kssels bearing the same name in higher verte
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dCuv. - jioyea
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yjus int.
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v.jigexT.
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vjugint
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VillK.
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v.cauL
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brates, approach each other in the center, and the first hint of their eventual fusion to create the posterior half of the future postcava is offered by a simple interanastomosis (fig. .3,*) at the level of the eighth spinal ganglia. Coincident with the merging of the subcardinals (figs. 4 and 5) occurs the fomiation of the proximal half of the postcava; this is already potentially present in the right vitelline vein, which, at first equal in size to the left (fig. 1, V. cm. mes), grows larger (figs. 2 to 5, v. hep. rev.), and,
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DEVELOPMENT, SYSTEMIC VENOUS PLAN, ANXIRA
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89
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traversing the liver, establishes continuity with an apparently independent segment which is developed between the liver and the right postcardinal (fig. 2). This segment soon becomes confluent with the latter vein at the level of the fourth spinal ganglia (fig. 3), and the postcaval trunk is complete. Obviously,
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vjujint
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latvcardpcot^
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vjugjirt aCuvt
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Yjujint
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5l.
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pronepi
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v.juj.int.
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-V5ubcla/.
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^-^ V. vert ant vsubcord _-n c(^ v.cav.poit
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'^— ^ corlym. posT.dc:
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v.caud.
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much of the blood in its return from the caudal regions of the body to the heart is now deflected through the postcava, and in time, as an increasingly greater volume of blood follows this more direct route, the portion of the original postcardinal veins between the postcava and the pronephric sinus of both sides gradually falls into disuse and atrophies, the right disappearing earlier than the left (figs. 5 to 7) .
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90
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OTTO F. KAMPMEIER
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>* Changes as far-reaching as the al)ove take place caudally. The most distal segment of the subcardinal (medial postcardinal division) does not fuse with its fellow, but undergoes reduction
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vjus.lnt
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il.proneph.
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-v.Jusext.
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sin.ven
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v,ju9 int
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corlym poitOexT
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corlym ■post 5ia
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v.caud
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Figure 6
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and finally breaks away (figs. 4 to 6), thus severing the connection between caudal vein and iiostcava. Hence, all of the blood from the hinder regions is compelled to flow through the expand
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DEVELOPMENT, SYSTEMIC VENOUS PLAN, ANURA
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91
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ing lateral postcardinal divisions which may now be called the venae renales advehentes (Jacobsen's veins, figs. 7 and 8), thence through the sinusoids of the mesonephroi to enter the postcava
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vju5.int
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cor lym postdex:
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ujug. int
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cor lym. posrsia
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Figure 7
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92 OTTO F. KAMPMEIER
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through the revehent branches. In the meantime, the paired abdominal vein has morped anteriorly into a single vessel which joins the hepatic portal vein (not shown in the diagrams) and so produces a second pathway of return for the blood-stream from the posterior region. CJradually, the two unfused and divergent rami of the abdominal vein remain united with the external iliac veins which extend out into the developing limb buds as the rudiments of the femoral veins. Extensions of the postcardinals backward along the caudal vein (fig. 6) represent the anlagen of the ischiadic veins (v. ischiad.) which enlarge as the hind extremities develop and the caudal vein degenerates. The transverse iliac veins (v. iliac trans.), obliquely connecting the external iliac and ischiadic veins, are a later acquisition (fig. 8).
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As the mesonephroi are progressively differentiated and as they assume the function of urea excretion, the pronephroi suffer regression in a corresponding degree (figs. 7 and 8). During the growth of the tadpole a marked shifting of relations occurs, for, as the diagrams indicate, the pronephroi in earlier stages lie slightly back of the niveau of the sinus venosus and are directly placed in the path of the postcardinals, but later, owing to the atrophy of the proximal segment of these channels, they come to lie anteriorly, at the junction of the external and internal jugulars.' In fact, the pronephric sinus at the time of metamorphosis forms the terminus of the internal jugular where it appears as a swelling (fig. 8), but the difference in diameter is gradually equalized by further reduction of the sinus. Changes like these are instrumental in bringing about the striking dissimilarities between the venous relations of the lymph hearts in embrj'onic and in adult stages. Further changes in this region that produce the definitive relations of the anterior Ijinph hearts to the veins are indicated in the following paragraph.
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.Associated with the alterations of the large venous trunks, radical modifications take place in the series of intersegmental veins. Another paper will show how the first three of these are intimately concerned in the development of certain lymph • In using the term 'external jugular vein,' I am following Gruby and Ecker; Goette and many other authors refer to this vein as the 'inferior jugular.'
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DEVELOPMENT, SYSTEMIC VENOUS PLAN, ANURA
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93
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atic channels, the third contributing largely to the formation of the a,nterior lymph heart (fig. 2, cor lym. ant.). Only the mouth of the anterior vertebral vein {v. vert, ant.) of later stages, in
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Y jug. int. V. vert, ant
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<z>
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cor lymant. 5in.
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v.brach.
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V vert po5t.
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94 OTTO F. KAMPMEIER
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other words, the efferent channel of the anterior lymph heart, can be considered as a direct transformation or derivative of the proximal portion of the third intersegmental vein, the remainder being an outgrowth from the latter just medial to the l3ini)ii-h(>art anlage. During the period of the degeneration of the anterior segments of the postcardinals and the consequent dwindling of the pronephric sinuses, each anterior vertebral vein, besides extending at first in a posterior direction, soon develops a second fork which extends forward and eventually establishes a connection with the internal jugular some distance anterior to the pronephric sinus. Sometime later, the original connection of the anterior vertebral vein with the vestige of the pronephric sinus, now the terminal portion of the internal jugular, breaks away, and the secondary junction farther cephalad becomes the permanent outlet of the lymph stream from the anterior lymph hearts. These changes are clearly expresedin the diagrams 5 to 8, inclusive.
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During development all of the intersegmental veins back of the anterior lymph hearts become interjoined by a longitudinal anastomosis (figs. 2 and 3) which may be termed the lateral vein (v. lat.) because it courses in the lateral-line region and is without doubt homologous with a similar vein in the tailed amphil)ians. Subsequently, the tennini of all intersegmentals except the 9th and 11th (fig. 7) in toad embryos become very nnich reduced or vanish, although variations happen, such as the persistence of the vessels in intervals otlier than those. The anterior one of the retained intersegmentals becomes the transverse piece or mouth of the dorsolumbar vein (figs. 7 and 8, r. dors, lumb.), while the greater extent of the lateral vein becomes its longitudinal portion (rami iliolumbalis and iliacus). While these changes are taking place, the posterior lymph heart {cor. lym. post.) on each side* develops from a lymphatic plexus along
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• Bufo po.sspssi's only one posterior lymph heart on each side. .Vmong the frogs there are multiple posterior lymph hearts, from two to four in number on eaeh Hide in the adults; thus in the American common species, Rnnn pipiens, there are normally two pairs of these 'diagram 9) with the occasional vestige of a third, present in the tadpole. The development of these hearts and their relation to the veins will be considered iti one of the subsequent papers.
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DEVELOPMENT, SYSTEMIC VENOUS PLAN, ANURA 95
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sin, ven. i
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v.cav.ant.
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v.cut. fern, post.
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Figure 9
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96 OTTO F. KAMPMEIER
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the lateral vein at the level of its 11th intersegmental branch (fig. 5). The proximal portion or junction of the latter branch with the postcardinal (vena renalis advehens) becomes the mouth or terminal segment of the posterior vertebral vein (v. vert, post.) and the caudal part of the lateral vein becomes its distal extension (figs. 7 and 8). A break occurring in the lateral vein between the two parts of it, referred to the longitudinal portion of the dorsolumbar and the posterior vertebral veins, respectively, estabhshes the independence of these two veins.
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In the meantime the posterior lymph hearts have formed a connection with the corresponding posterior vertebral veins, so that these channels now become the outlet of the lymphatic drainage of the posterior region of the body. The shifting of the mouth of the posterior vertebral vein back along the ischiadic vein uj) to the point where the transverse iliac vein is forming is clearly indicated in figures 7 and 8. These diagrams show how easily the variations that are so common arise by the expansion, reduction, or persistence of different segments of the originally symmetrical intersegmental veins, resulting in different relations with the main venous trunks.
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The degree of displacement, during development, of the various components of the venous conduit system, brought about by the more rapid elongation of some and the suppression of others, may be readily determined by comparing the successive stages with reference to the relatively fixed positions of the spinal ganglia, as indicated in the diagrams.
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Resunicn por el autor, II. E. Jordan, Universidad de \'iiginia.
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Estudios sobre la estructura del musculo estriado.
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\' 1 1 . El desarroUo del sarcostflo del musculo alar de la avispa,
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con consideraciones sobre la base fisicoqufmica
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de la contracci6n.
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La estructura del sarc6mero del relativamente grosero sarcostilo del musculo alar de la avfspa susministra la base de un intento de exi)licaci6n fisicoquiniica consistente sobre la contracci6n muscular. Las metafibrillas extremadamente pequenas que constituyen este sarcostilo, hom61ogo de la miofibrilla del musculo estriado de los vertebrados, exhiben durante la contracci6n exactamente los mismos cambios estructurales que la fibra muscular estriada voluntaria en conjunto. El cambio esencial durante la contracci6n se refiere a la divisi6n igual de la substancia fuertemente tingible del disco Q al nivel del mesofragma y el movimiento de las mitades resultantes en direcciones opuestas, aplicdndose contra los telofragmas terminales del sarc6mero, donde se forman las bandas de contracci6n. La causa de la contracci6n muscular esta localizada en este moviniiento de cristaloides entre las partfculas coloidales (submicras) de los segmenos claros terminales. El acortamiento y aumento de espesor de los sarc6meros durante la contracci6n se interpreta como el resultado de un cambio en la forma de las partfculas coloidales intrafibrilares que pasan de la forma elipsoidal a la esf^rica, a causa de un aumento en su tensi6n superficial resultante de la disminuci6n de sus cargas el<>ctricas suj)erficiales, la cual sigue al paso de electrolitos entre ellas durante el movimiento de la substancia fuertemente tingible desde el mesofragma a los telofragmas.
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Trannlntion by J(M^ F Nontdrt Cornell rnivrnillv Mnliral C*<illi>Kr. \ Y
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AtfTBOR 8 ABSTRACT OF THIS PAPER ISSUED BY THE BIBLIOGRAPHIC SERVICE. MAY 24
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STUDIES ON STRIPED MUSCLE STRUCTURE
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VII. THE DEVELOPMENT OF THE SARCOSTYLE OF THE WING MUSCLE OF THE WASP, WITH A CONSIDERATION OF THE PHYSICOCHEMICAL BASIS OF CONTRACTION
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H. E. JORDAN Department of Histology and Embryology, University of Virginia
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THIRTEEN FIGURES (tWO PLATEs)
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INTRODUCTION
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In the last number of this series of studies' it was shown that the constituent sarcostyles of the wing muscle of the wasp exhibit the same changes during contraction, with respect to the cross-striations, as do the complete fibers of striped muscle generally, namely, a reversal of striations as regards a deeply staining substance of the dim disc. It was assumed that the relatively coarse, cylindric sarcostyle of the wasp's wing muscle is the homologue of the more delicate myofibrils of vertebrate striped muscle. If this assumption accords with the facts, then Schaefer's** explanation of the appearance of a reversal of striations during contraction, as an optical illusion due to the accumulation of intersarcostylic fluid at the telophragma levels of relative constriction, must be erroneous. Moreover, the idea that this sarcostyle during functional contraction swells at the levels of the dim discs, thus producing a relative constriction at the level of the telophragma, is itself erroneous. As was shown in the previous number, ' the beaded condition of the sarcostj'le is the result of an artificial contraction following the osmotic action of a hypotonic medium. The functionally contracted sarcostyle, while it shortens and thickens, maintains meanwhile, nevertheless, a straight, unbeaded contour. None the less it seems desirable to establish definitely the actual morphologic status of the wasp's \\ing-muscle sarcostyle by a study of its development.
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97
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98 H. E. JORDAN
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This is the primary purpose of this investigation, namely, to trace the developmental history- of the wasp's wing-nmscle sarcostyle with a \'iew to determining its value in terms of the elementary myofibril of vertebrate striped muscle. The evidence which will be given below seems conclusive that the sarcostyle of the wasp's wing nmscle and the myofibril of vertebrate striped muscle are actually strictly homologous elements. This being so, it follows that in our efforts to discover the ultimate physicochemical basis of contraction we may more profitably, and quite legitimately and confidently, confine ourselves to the relatively much coarser sarcostyles of certain insects' wing muscle (e.g., Diptera, Hymenoptera, and Coleoptera). The second purpose of this investigation is finally to attempt a physicochemical interpretation of the structural changes suffered by the sarcostyle during contraction, and to formulate a consistent hypothesis in explanation of the cause of muscle contraction. The entire series of these studies on muscle structure had for one of its chief objects the accumulation of sufficiently numerous and precise data for the establishment of a correct physicochemical interpretation of muscular contraction.
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M.\TERI.\L .\XD METHODS
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The material available for this study consists of two fairly complete series of specimens ranging from the newly hatched larva to the older pupae, one series fixed in 95 per cent alcohol, the other in a 10 per cent solution of neutral formol. For this material I am indebted to Mr. Massie Page. For the purposes of the present problem we may confine ourselves to four salient developmental stages: 1) the oldest larval stage (or youngest pupal stage), namely, one in which the thorax is outlined and wing pads are discernible, but no external leg rudiments; 2) an intermediate white pupa; 3) a later gray, or slightly pigmented, pupa, and, 4) the black, almost mature, pupa. The thorax was embedded in jiaraffin. Sections were cut at An, and stained with iron-hematoxylin, followed in some cases by eosin counterstain.
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STRIPED MUSCLE STRXJCTURE 99
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DESCRIPTION
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In the youngest, legless pupal stages very delicate wings are already present. Serial sections through the thorax show the imaginal discs still in continuity with the ectoderm ventrocaudally. Here, then, occur the initial myoblasts (fig. 1, a and 6). Older stages in the muscle histogenesis occur anterodorsally (fig. 3 and 4). Between these terminal levels occur intermediate developmental stages (fig. 2, c).
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The initial myoblasts are long, fusiform elements with a vesicular, centrally located nucleus. The nucleus originally contains a single, dense, chromatic nucleolus. The latter subsequently divides, the nucleus now containing a pair of nucleoli. This condition foreshadows the ensuing direct nuclear division. The myoblasts fuse terminally, their tapering ends overlapping (fig. 1, b), to form the definitive muscle fibers. Meanwhile the nuclei multiply greatly by amitotic division. No mitotic figures were seen in the myoblasts or later muscle fibers at any stage. The muscle fiber accordingly arises by fusion of originally discrete cells, not solely and primarily by growth of the myoblasts. The nuclei multiply by direct division chiefly in planes perpendicular to the long axis of the myoblasts, thus forming axial columns of nuclei (fig. I, b); but to some extent also by division in the longitudinal plane, thus originating more peripheral nuclei. Appearances like those illustrated in figure 2, c, represent in part the latter sort of division, but in part also no doubt levels of sections where the tapering ends of fusing myoblasts overlapped.
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Already in the earliest myoblasts, like those of figure 1, a, an occasional peripheral myofibril is faintly discernible. The nature of this material does not permit of any definite statement regarding the origin of the myofibrils. I am unable to determine whether the original fibrils arise as such or by the alinement and subsequent coalescence of precursory myochondria. Nor can I be quite certain whether later fibrils arise by longitudinal division of preexisting myofibrils, or independently. I incline to think that the later myofibrils arise chiefly independently; at
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100 H. K. JORDAN
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any rate, there is no clear evidence of a longitudinal splitting. The fibrils soon extend uninterruptedly through several original cell limits, and they remain for a relatively long time homogeneous. In figure 2 (a and b) are illustrated transverse sections of myoblasts corresponding with a and b of figure 1. Illustration c of figure 2 represents an older myoblast. Connective-tissue cells occur among the mj^oblasts. At least some of these divide by mitosis. Many of these cells become fatcells. The cell c.t. of figure 2 is at an early stage of differentiation into a fat-cell.
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The earUer muscle fibers, formed by the fusion of myoblasts, grow rapidly in diameter (fig. 3). Both nuclei and myofibrils meanwhile undergo enormous numerical increase. In a transverse section (fig. 3) the nuclei, now granular and more chromatic, appear to be scattered at random. Longitudinal sections of fillers at this stage (fig. 4), however, show that the nuclei are arranged in long colunms, in single or double file. The connective tissue cells have also meanwhile increased greatly in number. The interfiber spaces have a diameter approximateh' equal to that of the nmscle fibers. These spaces are closely packed with stout, fusiform, and irregular connective-tissue cells. The latter subsequently differentiate largely into huge fat-cells. The myofibrils are still homogeneous and quite delicate. In transverse section they have the appearance of fine granules (fig. 3).
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Passing now from the stage of the oldest larva to that of the white pupa, with well-developed wings and legs, the wing-muscle fibers are seen to have enlarged enormously (fig. 5). The nuclei are numerous, but of smaller size in transverse section than in the preceding stage. Longitudinal sections of such fibers (fig. 6) reveal the fact that many of the nuclei are now greatly elongated elements. These continue to divide amitotically. The fiber is enveloped by a delicate sarcolemma. In certain cross-sections the peripheral myofibrils appear to be arranged in radial lines (fig. 5). This is the sole evidence that myofibrils may in part arise by longitudinal splitting of preexisting fil)rils. The myofibrils are now relatively coarse (figs. 5 and 6), but still clearly unstriped, and between the fibrils appears a very finely granular sarcoplasm (fig. 6).
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STRIPED MUSCLE STRUCTURE 101
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Thus far there is no indication of even a telophragma. In a slightly older pupal stage (gray pupa), however, this membrane has made its appearance (fig. 10). The myofibrils, or sarcostyles, are now relatively very coarse, as may be seen by comparing figure 7 with figure 5 of the previous stage, and with figure 8 from the adult muscle. The stages of muscle development in the gray pupa are of the utmost significance in this connection. We meet here with the initial steps in the origin of the crossstriations due to the presence of dim discs. Certain large masses of fibers are composed of sarcostyles in which only the telophragmata have appeared (fig. 9^ a). In other masses the sarcostyles contain also delicate, but deeply staining, Q-discs (fig. 9, b) . In such sarcostyles the telophragma has changed to an only relatively faintly staining membrane. Still other large masses of fibers consist of sarcostyles with relatively wide Q-discs (fig. 9, c). In certain other groups of fibers the Q-discs appear double (fig. 9, d), and occasional sarcostyles of such groups reveal very clearly constituent finer elements, the metafibrils (fig. 9, e). The clear indication of metafibrils, as in e of figure 9, may probably represent an artificial condition ; but that the sarcostyles actuaU}^ are composed of still finer fibrils seems demonstrated by the conditions which obtain where the muscle is attached to the hypoderm (fig. 10). Here the sarcostyles appear to break up into very fine 'tendinous' fibrils. The transition from muscle to tendon appears to be through direct continuity of muscular metafibrils and tendon fibrils The latter stain deeply in very dilute solutions of eosin, in contrast with the muscle which remains unstained. The metafibrillar composition of the sarcostyles is a point of cardinal significance with respect to the phj^sicochemical explanation of contraction, and will be fully discussed below.
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The order of development of the cross-striations here disclosed is also a fact of much importance. The Q-disc appears only after the telophragma becomes discernible. The Q-discs are at first only very delicate, and only gradually attain their typical width between successive telophragmata. Coincident with the appearance of deeply staining Q-discs, the telophragmata suffer
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THE ANATOMICAL BECOHD, VOL. 19, NO. 2
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102 H. E. JORDAN
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a diminution of staining intensity. The meaning of the double condition of the Q-dises, as in figure 9, d, is uncertain. It may have the same significance as in the mature sarcostyles, namely, indicative of an earh* phase of contraction.
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The foregoing observations are specially significant bj- reason of the light they throw on the question of the function of the telophragmata. The data strongly suggest that the telophragmata furnisli the pathways along which are transported the materials which contribute to the formation of the dim discs, as well as the materials which supplj' the nutritive demands of the sarcost\-les. The genetic order of events here revealed ex])lains the horizontal alinement of striations in cross-strijK-d muscle. This matter also will be reverted to and more fully discussed below.
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Thus far no evidence appears, either in the formalin or alcoholfixed j)rej)arations of sarcosomes. The latter appear first in formalin-fixed muscle of the almost mature black pupa (figs. 11 and 12). A largely lipoid nature of these sarcosomes is suggested by the fact that they entirely disappear in muscle of this stage fixed in 95 per cent alcohol. The sarcostyles have attained almost their definitive diameter (compare figs. 12 and 8 and figs. 11 and 13). In longitudinal sections (fig. 11) the sarcosomes appear spheroidal, but transverse section at this stage reveal the fact that they are alreadj^ laterally somewhat compres.sed, and so possess short, blunt, lateral wings (fig. 12). Generally only two sarcosomes occur to an intertelophragma .space, indicating that the teloj)lniigniata ofTer an efTective liarrier against their pas.sage through these levels, and suggesting that the materials for their elaI)oration were also transported through the telophragmata, a sarcosome each being contributed by one telophragma. Comparison of figure 12 with figure 8, the latter from an adult muscle, shows that the sarcosomes undergo considerable subsequent growth, a circumstance involving still greater compression between adjacent sarcostyles, with the formation of longer, thinner wing processes. The relatively late origin of the sarcosomes, that is, just prior to functional activity of the wings, suggests a close relation between
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STRIPED MUSCLE STRUCTURE 103
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sarcosomes and the metabolic requirements of the relatively very rapidly contracting wing muscle.
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In figure 13 are illustrated three successive stages in the contraction of the sarcostyle of the wing muscle fiber of an adult wasp. The sarcostyle a is in a condition of repose. The sarcostyle b is at an early phase of contraction. The Q-disc has become bisected by the appearance of an H-disc. The deeply staining substance of Q is accumulating at the levels nearest the telophragmata. The sarcostyle c is at a still later phase, when the deeply staining substance of the sarcoplasm has aggregated about the telophragma, so that now this membrane bisects a dark disc, instead of bisecting a light disc as previously. A true reversal of striations, as regards this deeply staining constituent of the sarcoplasm, has been effected. Sarcostyle d is in almost complete contraction. The sarcostyle has become thicker, and the sarcomeres relatively shortened. The deeply staining substance about Z in sarcostyle c has here condensed so as to form a contraction band of the contracted fiber. The double nature of this band is clearly shown in sarcostyle d. The telophragmata are, however, no longer discernible. The optical disappearance of the membrane Z in sarcostyle d is interpreted as resulting from the thickening of the sarcostyle, effecting thus a drawing out radially and a consequent thinning of this membrane to a point where it is no longer within the range of microscopic vision.
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The above seriation of stages in contraction of the adult sarcostyle gives the key for the interpretation of figures 11 and 9, d, of immature sarcostyles. Sarcostyle d of figure 9 would thus appear to be in an early stage of contraction, the sarcostyle of figure 11 at a later stage corresponding with that of c of figure 13. Apparently the immature sarcostyles are capable of some degree of functional contraction even before the wrings are moved in flight.
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104 H. E. JORDAN
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DISCUSSION
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The foregoing description shows that the wing-muscle fiber of the wasp is essentially homologous with voluiitarj^ stripednuiscle fibers generally. The liber is a multinucleated structure resulting from the fusion of originallj" discrete myoblasts, and subsequent growth, accompanied by an increase in the number of myofibrils and by the amitotic multiplication of the nuclei. The fibrils first appear as homogeneous elements, which only later become cross-striped. The wing muscle of the wasp, as that of Hymenoptera, Diptera, and Coleoptera generally, differs, however, from the usual type of voluntary striped muscle, in the definitive stages of its differentiation, in that its fibrils grow to relatively enormous radial dimensions. But the developmental history of this relati\oly very coarse sarcostyle demonstrates its strict homology with the more delicate myofibrils of vertebrate skeletal muscle.
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The question then arises concerning the functional significance of the relatively coarse sarcostj'lc of certain insects' wing muscle. Clearly the coarse, cylindric condition of the sarcostyle bears no direct causal relation to flight as such even among insects, since in the Orthoptera and certain Odanafa the wing muscle fibers of the thorax are characterized by lamellar 'sarcostyles' with constituent very delicate myofibrils. When we seek for a possible explanation of the difference in girth of sarcostyles in the several groups of insects, we note the fact that what distinguishes the flight of Di])tera, Hymenoptera, and Coleoptera from that of the Orthoptera, for example, is not so much the rapidity of flight as the ability on the part of the former groups to sustain rapid flight for relativel}' long periods of time. The suggestion then presents it.self that a relatively coarse type of sarcostyle, characteristic of wing muscle of which is demanded long-continued function, may somehow better subserve the conditions of this demand than a structure characterized by relatively delicate cylindric or by lamellar sarcostyles. Such hypothesis is suppf»rtcd also by the fact that the sarcostyles of the analogous pectoral muscles of thf> humming bird and the bat are
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STIUPED MUSCLE STRUCTURE 105
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relatively coarse cylindric structures. However, all speculations along these lines lose plausibility in view of the definite fact that also the coarse, apparently unitary, sarcostyles of wasp wing muscle resolve themselves finally into extremely minute constituent fibrils (metafibrils). This is true also of the lamellar type of wing nmscle sarcostyle (e.g., mantis'). It might then perhaps be argued that the coarse, so-called sarcostyle of the wasp's wing muscle is not actually the homologue of the myofibrils of, for example, human leg muscle, but in fact represents a fascicle of such fibril homologues. The apparent force of such argument, however, is neutralized by the fact that also the myofibrils of mammalian skeletal muscle may be seen to consist of collections of still finer fibrils. The sarcostyle of the wasp's wing muscle differs, moreover, from the lamellar, so-called sarcostyle of Orthoptera, in that the latter includes relatively fewer constituent fibrils and relatively much larger quantities of intrasarcostylic non-fibrillar sarcoplasm. Successively more detailed analysis of muscular fibrils reveals successively finer constituent meta-fibrils up to the limits of visiblitj^. As above described, however, and already explained, the early stages in the development of the wasp's wing-muscle sarcostyle show that it is strictly homologous with the myofibril of vertebrate striped muscle. Clearly, also, rapidity of function, or long-sustained function, is not directly related to complexity of cross-striation; for the wasp's wing muscle, and vertebrate cardiac muscle, is characterized by a relative simplicity of striation. Complexity of striation, resulting from the presence of an additional N-disc, as in insect leg muscle generally, would thus appear to be related to force of function rather than to rapidity or long continuance of function.
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Insect wing muscle generally, however, differs from voluntary striped muscle of vertebrates in the occurrence of numerous, relatively' large sarcoplasmic granules or sarcosomes in the former. But comparable elements occur also in the analogous pectoral muscles of bats and birds (Thulin"'), and in mammalian heart muscle (Bullard'). The common factor in the conditions underlying the peculiar function of these three types of muscle is the
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infi 11. K. JORDAN
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ability of loiiR-sustainod function. The evidence suggests that largo and al>undant sarcosoines subserve the peculiar metabolic nee<ls of muscles -which act continuously for long periods of time. The absence generally of at least large and abundant sarcosomes in insect leg muscle, and in vertebrate skeletal muscle generally, suggests that forceful function only at intervals does not necessitate exactly the same type, or at least the same degree, of support of its metabolic requirements.
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The sarcosomes develop relatively late. They appear first in the almost mature (black) pupa (fig. 11). They are at first spherical in shape; subsequentlj-^ they become modified into winged elements, the result of mutual pressure between the adjacent growing sarcostyles and the enlargmg sarcosomes. As was suggested in a previous article,' the winged type of sarcosome probably largely persists throughout the life of the individual, ^licrochemical evidence was also given indicating that, besides a predominant lipoid constituent, the sarcosomes, at least in the later phases of elaboration, include an additional substance, possibly a carbohydrate. The verj' definite arrangement of the first formed, spherical sarcosomes, two to each sarcomeric interval, suggests that the material for their elaboration enters the intersarcostjdic spaces via the telophragmata.
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A detail in muscle histogenesis about which there has been much confusion and unprofitable speculation concerns the fact of the regular horizontal alinement of identically differentiated levels of the cross-strii^ed myofibrils of a striped muscle fiber. The question arises as to how these alternating discs of adjacent fibrils are first brought into horizontal alinement. If the crossstriped myofiijrils arise originally independently of telophragmata, as the illustrations of Ciodlewski^' and of Luna" for example, purjwrt to indicate, then it is almost inconceivable how they may subsequently be brought into horizontal alinement. ^^^latever idea different investigators may hold regarding the origin of the initial myofibrils in various instances, whether as fibrils, mitochondria, or as prefibrillar myochondria which subsequently coalesce to form fibrils, all agree that the first genuine myofibrils are originally apparently homogeneous and only sub
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STRIPED MUSCLE STRUCTURE 107
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sequently become cross-striped.' The illustrations of Godlewski, while showing cross-striped myofibrils unconnected by telophragmata in young myoblasts of mammals, give no indication of how the secondary myofibrils originate. Possibly Godlewski failed, or was unable by reason of their extreme tenuity, to see the telophragmata actually spanning the interfibrillar spaces among the original myofibrils. Be this as it may, we possess two definite observations which explain how this transverse alinement of identically differentiated levels of the myofibrils of a muscle fiber is produced.
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The clearest evidence concerning this point accrues from the present investigation. It seems perfectly plain in this material that telophragmata precede the appearance of Q-discs (figs. 9 and 10). It was shown in previous papers^ "^ that the telophragmata are intimately connected with the sarcostyles and with the peripheral sarcolemma. In this way each sarcostyle is brought into relation with the interfiber tissue spaces and thus with the nutritive tissue fluid. Assuming that the telophragmata are pathways for the entrance and exit of materials between the
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' M. R. Lewis, however, claims that in the myocardium of the chick embryo it can be demonstrated by a certain fixing and staining technic that the 'fibrils' are completely cross-striated from their first appearance (Johns Hopkins Hospital Bulletin, vol. 30, p. 1). Moreover, she interprets the 'fibrils' as fixation prodwcts, a view long since urged for striped muscle geneally by Van Gehuchten (La Cellule, T. 4, p. 247, 1888), but never widely accepted. The cross-striations she regards as genuine fundamental structural features of the myoblast as a whole. If the conclusion here reached with regard to the artificial nature of the fibrils of the primitive myocardium of the chick were applied to the wing muscles of the wasp, we would be obliged to interpret the sarcostyle (homologue of the vertebrate myofibril, as above demonstrated) of the latter muscle as a developed and differentiated fixation product; since, no one I suppose, would seriously attempt to explain this definitive sarcostyle of adult wing muscle of wasp as also an artifact. It maj' be suggested that the reason why the primitive myofibrils described by certain investigators in cardiac muscle are not discernible microscopically in living myoblasts is not because they are not actually present, but because they are relatively fluid and because in consequence the refractive index of their sarcoplasm is so close to that of the interfibrillar sarcoplasm that the contrast between the two is insufficient to permit of clear differentiation under the microscope. The coagulative effect of fixation may bring about a greater relative difference between the refractive indices of the two sarcoplasmic colloids, and so render visible the denser fundamental sarcoplasmic fibrils.
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108 H. E. JORDAN
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sarcostyles and the intcrfiber tissue spaces (and this would appear to be their chief fuiu-tion), it becomes clear why the secondary modification of the originally homogeneous sarcostyles, namely, the formation of the Q-discs, follows the development of the telophragmata. Such genetic course explains at once the reason for the maintenance of a strict transverse alinemcnt. The investigations of ^lacallum'- and of ]\Ienten have shown that the dim discs contain potassium salts, chlorides, and phosphates. The presence of these substances in these regions may be the reason for their deeper staining capacity. These substances, considered physicochemically, are soluble crystalloids, at least in part electrol}i;es, and their segregation in the middle of the colloidal sarcomeres against the mesophragma, after entrance is thus explained.
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The difference in staining reaction of the telophragmata at the several successive earh' stages in the development, from the viewpoint of the relative amount of Q-substance, supi)orts the idea here advocated, namely, that the materials for the production and growth of the Q-discs enter via the telophragmata. In figure 9, a, the telophragmata are relatively coarse and stain deeply. In h, where a thin Q-disc has ai)])eared, the telophragmata are now delicate and relatively pale. The sarcostyle a may be interpreted as at the stage where the telophragmata are saturated with the deeply staining material, which in h has become segregated in the delicate Q-disc. To the latter is later added more of similar material to produce the relatively thick Q-<lisc of sarcostyle c. In view of tlie fact that the sarcostyles are closely connected with the telophragmata, the subsequently stratified sarcostyles (differentiating in the manner indicated through segregation of ciystalloids entering the colloidal sarcomeres through the telophragmata) nnist of necessity hold their alternating .strata in horizontal alinemcnt.
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The other pertinent observation in this connection concerns the mode of the development of the my()fil)rils in the body muscle of the newly hatched rainbow trout." The same histogenetic sieries of events in trout has been described also by Heidenhain.* Here the myoblasts originally contain a single, coarse, homo
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STRIPED MUSCLE STRUCTURE 109 geneous, deeply staining, cylindric myofibril lying close to the nuclear wall within the cytoplasm. The origin of this initial sarcostyle could not be determined. This prmiordial sarcostyle produces four secondary sarcostyles by two practically simultaneous longitudinal divisions. These secondary sarcostyles assume a stout lamellar form, and subsequent sarcostyles arise only by successive radial and central longitudinal fissions. Thus while the sarcostyles, both peripheral lamellar and central cylindric, become cross-striped during the early stages of histogenesis, all subsequent myofibrils must maintain a similar ahnement of their different alternating strata by reason of their origin by longitudinal division of already striped fibrils and their continued interconnection through the original telophragmata. Telophragmata are discernible following the first division of the initial sarcostyle. The available definite evidence therefore indicates that the cross-striations, as regards the Q-discs, only follows the appearance of telophragmata connecting with the peripheral sarcolemma, and so with the interfiber tissue spaces; and that the stratification results from the intake via the telophragmata of soluble crystalloids which become segregated in the Q-disc.
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The foregoing descriptions and discussions, together with the data comprised in the previous papers of this series, lead naturally to an attempt to formulate a correct interpretation of the structural changes which the sarcostyle undergoes during contraction, in terms of physicochemical factors, and to an effort to explain muscle contraction in terms of these changes. The specific central problem narrows itself down to a question of the intimate structure and physical chemistry of the contracting single sarcomere of the relatively coarse sarcostyle of the wasp's wing muscle.
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The sarcomere is bounded at both ends by a true membrane, the telophragma. Its middle is occupied by a disc of variable width, the so-called Q- or dim disc. This disc is composed of a substance which appears darker in unstained preparations, and which takes a deeper stain in fixed preparations treated with basic dyes. It contrasts in these respects with the lighter por
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1 10 H. K. JORDAN
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tions, halves of so-called J- or clear discs, intervening between it nnd the terminal telophrapniata. The sarcomere is Innuuled l)erii)herally l)y a layer which lias theproperties of a semipermeable membrane, as demonstrated bj' its response to hypo- and hyper tonic salt solutions. This layer, the sarcostylic membrane, is intimately connected with the telophragmata. Bisecting the Qdisc there occurs a delicate dividing structure, presumably a membrane, as demonstrated by the equal division of this disc in contraction along the midline, the niesophragma. This membrane, however, is not discernible as such in this sarcomere under the highest powers of the microscope. Minute analysis reveals the fact that the apparent Ij- homogeneous sarcomere consists in fact of ultimate metatibrils. The latter are intimatelj^ attached to the telophragmata. Macallum'- and Menten" have shown that the Q-disc contains segregated chlorides, phosphates, and potassium salts. The presence of these substances in this area prcsumablj' accounts for the 'dim' appearance and the deeper staining capacity, possibly also for the relatively greater anisotropy, of this disc in contrast with the terminal J-segments. These salts represent soluble crystalloids, therefore, at least in part, electrolytes, and give to the Q-disc a composition physicochemicalh' different from the predominantly colloidal terminal clear portions. The sarcomere, tlierefore, consists of a cylinder of minute fibrils enveloped bj' a peripheral membrane, each colloidal fibril containing medially a mass of segregated crystalloids. Through the terminal telophragmata of the sarcomere, each fibril (metaHl)ril) is placed in capillar}' relation with the intersarcostjlic fluid spaces. Presumably there exist between the metafibrils capillary interfibrillar canaliculi. When the muscle contracts, the jiredominanth- crystalloidal medial disc (Q-disc) of each metafiliril of the sarcostyle divides along the midline (mesophragma level) and the resulting halves move in opposite directions to fuse with similar halves, from successive sarcomeres, along the terminal telophragmata, thus forming contraction l)ands. The contraction bands accordingly' represent discs of predominantly crystalloidal composition, and a reversal of strata (striations) as regards the deeply staining crystalloidal substance of ♦he relaxed sarcostyle has occurred during contraction.
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STRIPED MUSCLE STRUCTURE 111
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The problem of muscle contraction, therefore, resolves itself, in the final anatysis, into a physicochemical explanation of the shortening and tliickening of the sarcomere in relation to the movement of a medial mass of crystalloids (electrolytes) through the terminal colloidal segments against the telophragma boundaries. It is here assumed that the movement of crystalloids among colloids is the cause, not simply the accompaniment, or the result, of contraction.
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The solution of the above-stated problem involves also an explanation of why, during the original determination of the stratified condition of the sarcostyle, the crystalloids, presumably^ entering terminallj^ via the telophragmata, take a definite median position. The attempt at such explanation must first be disposed of. In regard to this aspect of the complete problem, we are actually deaUng with a colloidal compartment, a hydrogel of myosin, bounded on the side where the crystalloidal substance presumably enters bj' a relatively coarse telophragma, at the opposite end where it is deposited, bj^ a relatively delicate mesophragma. WTien crystalloids mingle with a colloid, the molecules of the latter suffer a change of surface electrical charges, and it may be assumed that the crj^staUoidal particles or ions are repelled (or perhaps simply passively carried by fluids, due to the fusion of collodial particles behind thus propelling fluids forward) to the lunit where thej^ are held by the mesophragma and the adjacent mass of electrol}i:es.- The electrical condition of the now polarized sarcomere maj' now be considered to be in stable equilibrium in the resting fiber. "\Miatever the original form or state of aggregation of the colloidal particles, the passage of the crystalloidal particles, and their
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-The manner of origin of the initial stratification may perhaps be comparable to that of the so-called Liesegang phenomenon of colloidal chemistry, which phenomenon occurs when a gel containing a substance in solution is treated with a second solution capable of reacting with the solution in the gel; e.g., when to a test-tube partly filled with 1 per cent agar gel containing calcium chloride is added a solution of sodium carbonate. The calcium carbonate formed by the interaction is deposited in strata throughout the agar cylinder (vide Hatschek, ".4n introduction to the physics and chemistry of colloids," p. 73, P. Blakiston's Son & Co., 1919).
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112 H. E. JORDAN
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segregation in the future Q-disc, must be considered to cause the assumption of an elUpsoidal form of the colloidal particles witli the long axis j)arallel to the length of the sarcostyle. Such original elongation of the colloidal particles may cause a certain amount of elongation or longitudinal growth of the prefunctional sarcostyle. A possible original change of form, under the influence of the entering crj'stalloids, from an ellipsoidal form (with long axis of colloidal particle parallel to length of fiber) to a spherical shape, would offer the same basis for a future contracticjn of the sarcomere, if we assume that the formation of the contraction band involves a change of form of the colloidal particles (due to alteration of surface tension) from a spheriodal form to an ellipsoidal form in which the long axis of the colloidal particle is placed at right angles to the long axis of the sarcostyle. .Vll things considered, however, the former alternative seems the more probable.
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\\'e may now proceed to consider contraction in the histologically mature sarcostyle. Contraction is initiated by a nervous stimulus. The latter may be regarded as a wave of negative electricity. We may suppose that the negative charge enters the sarcomere at the level of the more delicate mesophragma. This disturbs the electrical potential and causes repulsion of the electrolytes; that is, the charged ions are made to travel from the level of the mesophragma through the adjacent colloidal area against the telophragmata, where contraction bands are formed. The movement of the electrolytes among the colloidal particles causes a change of surface energy, hence of surface tension, by reason of the discharge of surface electrical charges and in conse(iuence a change of shape of the colloidal particles. If we assume that this change of shape is one of change from an ellipsoidal fomi (oriented in the longitudinal plane) to a spheroidal shape, the shortening and thickening of the constituent sarcomeres of the sarcostyles, and thus nmscle contraction, is accounted for. The formation of the contraction band again results in a condition of stable electrical eciuilibrium, which latter is again upset when the particular nervous stimulus is internipted, and a movement of the electrolytes is started in the opposite direction, resulting thus in the characteristic strati
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STRIPED MUSCLE STRUCTURE 113
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fication and the electrically stable condition of the sarcostyle in repose. If this is in fact the central significance of the deeply staining Q-substance, its variable relative width in different fibers of the same muscle becomes intelligible: its relative quantity within certain limits may not be a fundamentally essential requirement for adequate function of the contractile mechanism; all that may be required is a certain minimal amount and hmitation within certain maximal amounts. Furthermore, the apparent relative amount of the Q-substance may be largely incidental to the degree of its concentration.
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Since I have previously deduced and supported the hypothesis that intercalated discs, characteristic of heart muscle, and occasionally found also under certain conditions in voluntary striped muscle/ represent in essence modified irreversible contraction bands, it seems demanded in this connection that the formation of these intercalated discs be also explained consistently with the above outline of muscle contraction. During muscle contraction lactic acid is formed, ^\^len a muscle is made to function to exhaustion, the amount of lactic acid is excessively increased. Acid has a precipitation or coagulative effect upon colloids and upon mixtures of colloids and crystalloids. Intercalated discs would thus find their explanation, in accordance with the above scheme of contraction, in the supposition of the production of a relatively excessive amount of lactic acid under certain conditions, sufficient to effect a precipitation, that is, an irreversible coagulation, of a part of, or an entire contraction band.
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The above-outlined physicochemical explanation of muscle contraction is in essence veiy similar to that presented bj^ Prenant, Bouin, and Maillard.'^ These histologists describe contraction as an electrocapillarj^ phenomenon. The cause of the shortening and thickening of the sarcomeres they also locate in a change of shape of the ultimate colloidal particles of the intrafibril sarcoplasm, following an alteration of electrical potential of opposite surfaces of contact of adjacent particles. But these authors do not carry their analysis and interpretation to the point above indicated with regard to the first appearance and the segregation of the crystalloids within the primitive colloidal
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114 II. E. JORDAN
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sarronicre, nor do they rccoKiiizc a niovenient of crystalloids during contraction from the nicsophragina to the telophragma, nor do they locate the cause of change of shape of colloidal particles specifically in the surface of contact between electrolytes and colloidal i>articles.
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Similarly l<illie's"' explanation of muscle contraction has a close resemblance to our hypothesis. However, Lillie conceives of the intimate structure of the sarcomeres in our opinion erroneously, in that he regards the dim Q-disc as the result solely of a greater concentration, or of a different state of aggregation, of colloidal particles at tliis level. This alleged constitution jiresupposes relatively large interstitial fluid-containing spaces in the clear J-disc. Nor does Lillie recognize a movement of dim substance during contraction. He does, however, assume a movement of interstitial fluid from M to Z, but only as an incidental result of the closer aggregation of the colloidal 'submicrons' of the dim disc. Lillie conceives of the energ>' of contraction as transformed surface energy of the ultimate structural element or colloidal particle (submicron) composing the fibril gel. The shortening and thickening of the sarcomere is thought to result from the massing of the colloidal particles in the 'anisotropic' segments, the massing itself resulting from the heightened surface tension resulting from diminished electrical surface polarization. He regards contraction as similar to reversible coagulation of colloids. This hypothesis, considered in detail, gives no clue for the consistent interpretation of intercalated discs. It is readily conceivable that the conditions here jiostulated might lead to an irreversible coagulation of sarcoplasmic colloids; but such areas of irreversibly coagulated sarcoplasm would be at the level of the mesophragma, according to Lillie's explanation, and not, as is actually the case, at the levels of the telophragmata.
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.\ccording to our hypothesis, on the contrarj', the shortening and thickening of the sarcomere, that is, contraction, results from the change of shape of the ultimate colloidal sarcoplasmic particlas following an increased surface tension, the latter resulting from decrease or disappearance of the surface charges of the
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STRIPED MUSCLE STRUCTURE 115
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(•olloidal particles accompanying the movement of electrolytes among them from the mesophragma to the telophragma, the movement being initiated by the disturbance of electrical potential of the membranes, primarily of the mesophragma, surrounding the sarcomere following the passage of nerve stimulus. It must be admitted, however, that a precipitation of colloidal particles by electrolytes would have essentially the same effect of shortening and thickening of the sarcomere as would a change of shape of the particles. But LilUe's hypothesis permits of no plausible explanation of the dim character of the contraction band. If, as Lillie assmnes, the Q-disc of the fibril in repose is 'dun' because of a closer aggregation of colloidal particles at this level, and if, as he further assumes, contraction is essentially a matter of a still closer massing of colloidal particles at this level, with a forcing of interstitial fluid into the telophragma borders of the clearer J-segments of the sarcomeres, then the latter areas should become Hghter instead of becoming darker, as they actually do become as parts of contraction bands. If the Q-discs are 'dim' because of a closer aggregation of colloidal particles here, then the 'dimness' of the contraction bands should consistently be explained in the same way; but that the latter are areas of closer aggregation of colloidal particles is in contradiction to the central idea in Lillie's hypothesis. Reconciliation of this damaging contradiction can be effected, and the integrity of Lillie's hj^jothesis maintained, onlj^ on the assumption that the Q-disc is dim because of the presence here of an additional darker, more fluid substance, which latter becomes forced against the telophragmata during contraction and here gives the darker color or 'dim' appearance also to the resulting contraction band. But when this further assumption has been added to the basic assumptions of Lillie's hypothesis, we are very close to the hypothesis here urged and supported, namely, that the cause of contraction is located in the final analysis in the fact of a movement of 'dim' substance among the colloidal particles of the sarcomere from M to Z. And in view of the demonstration of the segregation of crj^stalloids in the dim discs (Q-disc and the contraction band) the latter hj-jiothesis would seem to be the most satisfactory alternative.
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116 H. E. JORDAN
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No hypothesis of imiscle contraction can of course be satisfactory that cannot be harnioiiizod with the principle of the conservation of energy. We must be able to find within the muscle, sources of energy apjiroxiinately equal in sum to the amount of energy expended l)y the functioning muscle; which energies must both be approximately equal to the underlying chemical energy of the metabolic processes of active muscle. The details of the exact relation between the chemical energy of nmscle metabolism and the postulated surface-tension energy of the sarcoplasmic particles need not be here considered. The energ}' of the nerve stinmlus need of course be only sufficient to start the initial link in the chain of chemical reactions of the metabolic processes underhing the assumed surface-tension energy of contraction. Lillie supports the hypothesis that the contractile energy of muscle is due to changes in surface tension of certain muscle elements by these statements:
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In contraction the surface tension of these elements is supposedly increased. If this increase of tension is sufficiently great, and the area of the active surface sufficiently large, the transfomiabie surfaceencrgj', which is measuretl bj- the product of these two factors, may be sufficient to account for the work done by the muscle in contraction There is ... . good reason to regard the ultimate coiloi(hil particles of the fibrils as corresponding to such elements. By their union to fonn larger particles, as in the general process of colloid-coagulation, sufficient mechanical energy to account for contraction might conceivably be freed, since the reduction of surface-area in such a process may be very great, implying a correspondingly large transformation of surface-energj" (p. 252).'
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In r^^'sumc?, the gist of our hypothesis involves the following assumptions, which are consistent with the fact of a movement of 'dim' substance from the Q-disc to the contraction band during contraction: The nerve .stimulus causes a movement of ions from M to Z effecting a change in shape of the colloidal particles from ellipsoidal to .spherical; cessation of stimulus, an instant return of ions from Z to M with a return to the original ellipsoidal form of the colloidal particle; the change in form of the
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• For a review of the earlier literature touching similar interpretations of muscle contraction, the reader is referred to Lillie's paper and to Schaefcr's textbook (p. 189).
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STRIPED MUSCLE STRUCTURE 117
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latter being the result of an alteration of surface tension following alternating increase and decrease of surface electrical charges under the influence of the reversal of the direction of the current of action and the moving electrolytes.
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The histologic data relative to the intimate structural changes in contracting muscle above given seem in strict accord with the conclusion that the source of the contracting energy of muscle resides in alterations of surface tension in the colloidal particles of the ultimate muscle fibrils. My conception of the physicochemical process in ultimate detaU differs from that of Lillie in essence only in that Lillie interprets contraction as the result of an aggregation or union (resembling reversible coagulation or precipitation) of the colloidal particles mainly in the Q-disc, with expression of interstitial fluid into the J-disc, following increase of surface tension due to decrease of surface electrical charges; while I view the histologic data (supplemented by the microchemical data of Macallum and of JMenten) as indicating an actual movement of soluble crystalloids (electrolytes) from the mesophragma to the telophragmata, which movement of electrolytes may be interpreted as the chief factor in effecting an increase of surface tension of the colloidal particles and so altering the shape of the particles, which alteration of shape, rather than a massing of the particles, effects a shortening and thickening of the sarcomeres.
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SUMMARY
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1. The relatively very coarse sarcostyle of the wing muscle of the wasp is strictly homologous with the mj'ofibril of vertebrate striped muscle. Both varieties of fibrils consist of bundles of extremely minute constituent metafibrils. The wasp's sarcostyle has an enveloping layer with the properties of an osmotic membrane, the sarcostylic membrane.
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2. The structural changes exhibited by a striped muscle fiber during contraction are the result of similar changes in the constituent metafibrils. The fundamental and essential change con THE ANATOMICAL nECORD. VOL. 10, NO. 2
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11^ H. E. JORDAN
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cerns the equal division at the level of the inesophraKiiia, and the subsequent movement, of the more deeply staining substance of the Q-disc, against the terminal telophragmata of the sarcomere, where are formed the contraction })ands.
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3. The salient histogenetic steps pccur in the following order: The myoblasts of the iniaginal disc difTerontiato from ectoderm; the lirst-formed myofibrils are homogeneous; the teloj)hragmata precede the appearance of the Q-discs; the latter are at first very delicate and only gradually acquire their tj-pical definitive width. The sarcosomes appear only relativel}^ late, shortly before functional activity of the wings.
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4. The order of development of the two chief cross-stripes, the connecting Z-membranes and the Q-discs, explains the exact horizontal alinement of similarly modified levels of the constituent fibrils of a striped muscle fiber. The telophragmata probabl}' function chiefly as the pathways along which the deeply staining substance of the Q-discs first enter the sarcostyle, and along which metabolic products pass to and fro between the sarcostyles and the interfiber tissue spaces.
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5. In the effort to disclose the ultimate physicochemical bases of muscle contraction, we may legitimately and confidently confine ourselves to the structure of the sarcomere of the relatively coarse myofibril (sarcostyle) of the wasp's wing muscle. The fundamental factor in muscle contraction is located in the movement of the deeply staining sul)stance of the Q-disc against the telophragmata in the formation of contraction bands. The concomitant shortening and thickening of the sarcomeres is interpreted as the result of a change in shape, from ellipsoidal to .spherical form of the ultimate colloidal particles of the intrafibril sarcoplasm, following an increase of surface tension of these particles (submicrons) resulting from a decrease of surface electrical charges due to the passage of electrolytes (crystalloids of the deeply staining substance of Q) among the colloidal particles.
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STRIPED MUSCLE STRUCTURE 119
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LITERATURE CITED
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1 Hdllard, II. II. 1916 On the occurrence and physiological significance of
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fat in the normiil myocardium and ntrioventricuhir syHtom (bundle of His), intcr.stitliil K>°aniiK'» (mitnrhiiii<lriiil and |>h>>.Mpholipinc8 in cardiac muscle. .\m. Jour. .Vnat., vol. 19. p. 1.
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2 GouLEWsKi, IC. 1901 Ueber die Entwirklung dcr qucrgestreiftcn musku losen Gewebcs. Krakauer .\nzciger fcitcd from Ileidcnhain).
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3 Heide.nh.mn-, M. 1911 Plasma und Zcllc, S. G41-648.
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4 IIeidenhain, M. 1913 Ueber die Kntstehung der quergestreiften Muskel substanz bei der Forelle. Bcitriige zur Teilkorperthcorie, II. Arch. f. mikr. Anat.. Bd. 83, S. 427. 3 Jordan, H. E. 1917 The microscopic structure of striped muscle of Limulus. Pub. no. 251, Carnegie Inst, of Wash., p. 273.
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6 1917 Studies on striped muscle structure. III. The comparative histologj' of cardiac and skeletal muscle of scorpion. .\nat. Rec, vol. 13, p. 1.
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7 1919 Studies on striped muscle stnicture. IV. Intercalated discs in voluntary striped muscle. Anat. Rec, vol. 16, p. 203.
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8 1919 Studies on striped muscle structure. V. The comparative histology of the leg and wing muscles of the mantis, with special reference to the N-discs and the sarcosomes. .\nat. Rec, vol. 16, p. 217.
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9 1920 Studies on striped muscle structure. VI. The comparative histology of the leg and wing muscles of the wa-^p, with special reference to the phenomenon of stripe reversal during contraction and to the genetic relationship between contraction bands and intercalated discs. .\m. Jour. Anat., vol. 27, p. 1.
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10 LiLLlE, R. S. 1912 The physiological significance of the segmented struc ture of the striated nmscle fiber. Science, vol. 36. p. 247.
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11 Luna, E. 1913 Sulla importanza dei condriosomi nella genesi dclle myo fibrillc. Arch. f. Zcllf., Bd. 9. S. 4.>S.
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12 Maoai,i,um. \. B. 1905 On the distribution of potassium in animal and
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vegetable colls. Jour. Physiol., vol. 32, p. 95.
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13 Mbnten, .Maud L. 1!X)S The distribution of fat. chlorides, phosphates,
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potassium and iron in striated muscle. Tran. Canadian Institute, vol. 8. p. 403.
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14 Phena.nt, A., BotJiN, P., ET Maillakd. L. 1904 Traitd d'Histologie, T. 1,
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p. 440.
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15 ScuAEFER, E. \. 1912 Textbook of microscopic anatomy. Longmans,
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Green & Co. 10 TintLiN, I. 1915 1st der Grundmembran eine konstant vorkommende Bildung in den quergestreiften Muskelfasern? .Vrch. f. mikr. .Vnat., Bd. SO. S. 31S.
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EXPLANATION OF FIGURES
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T!if drawings were made from sections of tissue fixed in 10 per cent formalin. The sections were cut at 1^. and stained with iron-hematoxylin. With the exception of figure 13. the magnification of the drawings is 1300 diameters. The section from which figure 10 was made was lightly counterstained with eosin.
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PLATE 1
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EXPLANATION OF FIGURES
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1 <j. Longitudinal section of myoblast immediately after separation from the imaginal disc. The originally single nucleolus has become divided in anticipation of the ensuing direct division of the nucleus. 6, Three slightly older, now multinucleated myoblasts, in process of fusion to form a muscle fiber. Delicute peripheral myofibrils are faintly discernible. The specimen from which these drawings were made was at the latest larval or earliest pupal stage; wing pads were present, but the legs had not yet appeared.
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2 a, b and c. Transverse sections of three successively older myoblasts from the same specimen as figure 1. Sections a and 6 correspond to <i and 6 of figure 1 ; c represents a slightly older stage, cut at the level of lateral fusion as indicated by the two radially adjacent nuclei, c.t., an intcrfiber connective-tissue cell in early stage of metamorphosis into a fat-cell.
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3 Transverse section of later wing-muscle fiber from same specimen. The nuclei are now very numerous and scattered apparently at random. The myofibrils are uniformlj- distributed throughout the sarcoplasm and appear as darker dots in transverse sections. <•.(., a connective-tissue cell. The latter are very numerous and completely fill the wide interfiber spaces.
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4 Longitudinal section of fiber like the one of figure 3. The homogeneous myofibrils are conspicuous between the columns of nuclei. The interfiber spaces are approximately of the width of the diameter of the fibers. These spaces are completely filled with short fusiform and polyhedral connective-tissue cells.
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5 Transverse section of older fiber, from white pujia (with wings and legs). The fibrils have become much coarser and appear radially disposed along the left border.
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120
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8TRIPED MUSCLE STRUCTURE H. E. jonnoN
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PLATE 1
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PLATE 2
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EXPLANATION OF F1GUKE8
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r> Loiiiiitudiiiiil siH-tion of filior like thiit of fig. 5. The nuclei are loiiR narrow oleiiieiits (livldiriK dirortly into smaller nuclei. Among the homogeneous coarse myofibrils are scattered smaller irregular granules. There is as yet no indication of telophnigmata or other stratification in the fibrils.
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7 IVri|iheral portion of older fiber in transverse section, showing the coarse myofibrils (sarcostyles), a iieripheral nvicleus. and the sarcolemma. Sarcosomes have not yet made their appearanre. The .section is of a later pupal stage (gray pupa).
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8 Portion of adull w ing-muscle fiber in transverse section, showing the coarser myofibrils and six included irregular sarcosomes.
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9 a. b, c, (I and e. Three successive stages in the later development of the myofibril, from a longittulinal section of the thoracic (wing) muscles of a gray pupa (same as fig. 7). a shows two adjacent fibrils in which only the Z stripe (telophragma) has appeared. This strijie stains very intensely at this stage. In fibril /> the Z-slripe is faint, and a deeply staining but thin Q-disc has appeared.' In c the Q-disc has become much thicker. </ and e are at the same stage of development, but in (I the (^-disc has become bisected and an H-dise has in eonsecpienee appeared, and in c the nietafibrillar constituent elements of the sarcostyle have become conspicuous.
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10 Longitudinal section through region of attachment of nuiscle to epidermis. The nucleus lies in the 'tendinous' portion of this connection. This tendinous portion stains much more deeply in a very dilute eosin eounterstain than the muscle. At the levels where the sarcostyles break up into the 'tendon fibrils' the telphragmata disappear.
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11 Small area of longitudinal section of wing-muscle sarcostyles of older (black! pupa. Between the sarcostyles are single rows of small oval sarcosomes, generally two to a sarcomeric interval.
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r2 Portion of a transverse section of a fiber like that of figure 11, including one nucleus. Many of the apparently oval sarcosomes are now seen to have lateral wing-like processes. Compare with figures 7 and 8.
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1.3 Sarcostyles of definitive wing muscle of adult wasp at four successive stages in contraction. Fibril o is in repose; b is in an early, r in a later stage of contraction; </ represents a contracted fibril with almost f\illy formed, double contraction band.
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12--J
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raiPED MUSCLE STRUCTURE
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H. E. JORDAN
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PLATE 2
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-J_.
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-1H
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Z •^•r<) ■<■>*
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e ~
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10
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Rosumen por la autora, Kaothe Weller Dewey, Universidail do Illinois.
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r(mtnbuci6n al osliulio dpi sistema linfiltico del ojo.
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La autora considcra a la (•ol()raci6n vital conio cl niojor medio para donioiistrar los capilaros linfaticos y espacios linfaticos del ojo, del inisiiio iiuulo <iue los de otras partes del euerpo. I.as eelulas endoteliales cjue tajjizan estos eanales tienen la propiedad de tenirse con e! colorante \ital. Los resultados de los experinientos eon la parafeiiileiidiaiiiiiia liaeen resaltar las difereneias eiitre los espacios de los tejidos y los espacios linfaticos, el plasma y la linfa jiropiament edieha. Las ohservaciones llevadas a cabo niediante el tenido vital eon referenda a su signifieaci6n presunta en el sistema linfiitico no estiin en eontradieei6n con los hechos anat6micos reconocidos. Aceptando cl hecho de que las c^lulas endoteliales vitalniente tenidas denotan la presencia de canales linfaticos, se eomprueba la ausencia de dichos canales en la c6rnea, niientras que la conjuntiva los posee abundantcs. La escler6tica posee muy pocos capilares linfaticos, que a veces faltan en absoluto; puedcn acompanar a los vasos sanguineos que la atraviesan. Tanijioeo existen en la retina. La coroides los presenta principalmente en los coriocapilares. La jilandula lagrimal. el tejido orbitario y los parpados presentan abundantes capilares linfaticos. No existen en el cartilago tarsal de los parpados. Las eelulas vitalniente tenidas son mas abundantes en el euerpo eiliar y, especialmente, en los procesos ciliares, que en cualquier otro parte del ojo. Esto coincide probableniente con niayores actividades funcionales, tales conio la intensa i)articii)aci6n en la secrecci6n del fluido intraocular. El iris estd provisto de esca.sos capilares linfaticos, a pesar de su rica irrigaci6n sanguinea. Esto indica (\w tal 6rgano no deseiniienii las mi.-inias actividades funcionales fine el euerpo eiliar.
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TrnrMlatiiin l>y Jim^> K. Nonidn Cornrll L'nivcraity Medical College. N. Y.
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AUTHOB e ABSTRACT OP THIS PAPER ISSUED BY THE BIBLIOQRAPHIC SERVICE, MAT 24
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A CONTRIBUTION TO THE STUDY OF THE LYMPHATIC SYSTEM OF THE EYE
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IvAETHE W. DEWEY Research Laboratory of the College of Dentistry, University of Illinois
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THREE FIGURES
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In view of the great interest which evidences of an etiological relationship between infectious processes about the teeth and pathological conditions in other regions are receiving in recent years, clinical and anatomical investigations vie with one another in furnishing the necessary scientific foundation for more or less empirical conclusions. Relations between certain affections of the eye and diseased teeth have been recognized since the remotest ages, but reliable reports of actually observed transmissions of pathological processes from the teeth to the eye are all of a relatively late date. The number of these published reports is not inconsiderable.' Little, however, is yet known concerning the routes of transmission that could in any way be considered as positive and final. The dental origin of cases of the so-called dental eye fistula, orbital phlegmon, and abscesses is revealed chiefly through the fact that the eye conditions either promptly disappeared with treatment of the involved teeth or that they developed upon the extraction of a tooth with or without involvement of the maxillary sinus. The traveling of the pus from diseased teeth to the orbit, as, for example, in phlegmon, has often been represented as being per continuitatem along the outer surface of the maxilla over the orbital border. Frequently a transmission by way of the \'eins is assumed, and also a few casual suggestions occur in the literature that the processes may progress by way of the lymphatics. The latter route, however, is probably more important and much more frequent than the
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'A report of clinical observations along these lines will be published in .\rchives of Ophthalmologj', July, entitled ".\ffections of the Eye from Diseased Teeth."
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125
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126 KAKTHE W. OEWEY
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scanty and incomplete statements concerning it would make us Relieve.
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The demonstration of direct comnuinieations between the lymph sujiply of the dental region and that of the ej'e is obviously difiicult. In ])rovious experimental work for the demonstration of the lymphatics of the dental pulp and the peridental membrane' - indications of extensive anastomoses in the lymph-supply of these two regions were sometimes incidentall}^ obtained. In injections by the derota method of Prussian blue into the gum tissue the fluid was not only forced through the bony tissue of the jaw into Ijnnph-vessels of the peridental membrane, but sometimes deep and superficial lymph-vessels of the infraorbital region were also injected. The looseness of the orbital tissue makes injections in the region of the eye unsuitai)le for purposes along these lines: the injection mass will follow the direction of the least resistance and fill the loose tissue of the orl)it. This occurs also in injecting the liuid through the infraorbital foramen, which is the most accessible place for reaching hnnph-vessels in either direction to the eye as well as the dental region.
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I'ntil recently our knowledge of the lymjih-supply of the eye region was very limited and it is still (|uite incomplete with regard to the lym!)hatic system of the ej'e proper. Bartels,' in I'.IOi), writes: "Nowhere besides in the lids and the conjunctivae have geiuiine lymi)h-vessels been surely demonstrated, while we may say that it has been shown with a proljability bordering on certainty, that in the cornea, the lens, aiid the vitreous body they are completely lacking. In fact, we need not look for a current of liuid in a stal)Ie oi)tic apparatus. It is <iuite dilTerent, however, in the other parts of (he eye which constantly have to perform most important work and where therefore correspondingly active metai)olic interchanges nuist be assunuul a priori. They have not yet been demonstrated, however."
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.\ lymphatic apparatus of the orbit has been demonstrated by Birch-Ilirschfeld.' That the existence of such a system may be jjresupposed has been claimed l)efore him l)y some writers who are unwilling to consider the lymphangiomas of the orbit as heteroj)lastic formations; the occurrence of these speaks for the
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LYMPHATIC SYSTEM OF THE EYE 127
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presence of Ijanphoid tissue in the orbit even if in such minute amounts as to escape microscopical observation. By methods which, according to Birch-Hirschfeld, produce an increased lymph secretion or Ijinph stasis resulting in dilatation of the lymphcapillaries, this author believes he has seen distinct hmiph spaces in the orbital tissue — in the lipoid tissue, the lacrimal gland, between the muscles, and in the neighborhood of the optic nerve and the periosteum. With his methods he could not demonstrate the direction in which the lymph flows off nor a connection with any lymi^h-gland. He belie\'es, howe\'er, we may assume that communication exists between these spaces and the lymphvessels of the nose, and that there is a connection between the orbital lymph system and that of the surrounding regions through the perivascular spaces about the vessels passing through the superior and inferior orbital fissures.
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Histologically, the demonstration of the minute lymph-vessels of most organs is very difficult. if notaltogetherimpossible. Postmortem, they are practically virtual spaces and the endothelial cells lining them are in general indistinguishable from the slender nuclei of the surrounding connective-tissue cells. In order to distend them and thereby render them more amenable to microscopic study Birch-Hirschfeld employed a drug which is known in pharmacology and toxicology' to produce chemosis and edema of the orbit, exophthalmus and increase of the iirtra-ocular pressure. This drug is paraphenylendiamine hydrochloride. He also made use of dionin, small pieces of which he introduced into the orbital tissue. The action of this drug is to cause dilatation of the capillaries and increase of the lymph excretion, and this is especially well demonstrated al^out the eye. Paraphenylendiamine, according to him, pi'oducos stasis of the Ijanph, and an increase of the secretion of the lacrimal gland, of the mucous secretion of the conjunctiva and the salivary glands. If a large dose is given, the edema of the orbit extends also to the face and the neck. Edema of the glottis is the final cause of death. Similar observations are reported by (Irunert,* ^latsinnoto,* Puppe.' The spaces in the orbital tissue and those in the lacrimal gland which Birch-Hirschfeld found dilated and filled
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128 KAETIIE \V. UEWKY
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with fluid after (iiainiiie poisoning arc believed by him to be lyMii)h-spaces, and he states that in some of the larger and medium-sized sjjaces he found a tlistinet endothelial membrane.
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These statements bj' Bireh-IIirsehfeld seemed to me of extreme imiiortance. If the observations eould b(> verified and his eonelusions shown to be right, the use of paraphenyleiidiamine shouUl enable me to prove the correctness of a view obtained from previous experimental work on vital staining, which, in the absence of more positive proofs, I could express only suggestively.* N'ital staining, I stated, may be the means of demonstrating the lymi)h-chamiels of origin in most organs of the body by exhibiting their endothelial cells which havo an affuiity for vital stains, (iranting the correctness of Birch-llirschfeld's observations, paraphenylendiamine should be a valuable aid in such investigations by demonstrating a lumen in such endothelial-clad lymphchannels.
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I tested this drug on two dogs, two cats, tea labbits, and ten frogs. The larger number of these animals were injected with lithium carmine ]>revious to their treatment with the diamine poison. The results of these experiments will be reported in detail in another paper as a question dealing largely with phannacology. They were disappointing to the extent that they contributed nothing to the main purpose of this study: the microscopical study of the tissues in diamine poisoning failed to reveal what I had expected to find. The dilated spaces in the edematous tissues are not lined with vitally stained endothelial cells. ^lost of them are simply surrounded by delicate fil)ers without any cellular elements; occasionally a slender nucleus maj' be seen in this wall, resembling as much the nucleus of a connectivetissue cell as that of a flat endothelial cell. Vitally' stained cells may be .seen near these spaces, but never so near as to justify the impression that they form any part of the wall. I am, however, not inclined to believe that these spaces are lymph-spaces, as Hirch-Ilirschfeld does, but consider them simply as tissue spaces and di.stended meshes in the connective tissue, nor do I regard the fluid as lJ^nph proper, but as a serous efTusion, plasma from the blood-vessels.
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LYMPHATIC SYSTEM OF THE EYE 129
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Sections from the edematous subcutaneous tissue of the face and over the lower jaw in rabbits show that all this tissue is split up into inniunerable spaces and sUts filled with fluid, to regard all of which as Ijinph-spaces, potential or actual, would not be reasonable. One of the chief effects of the drug seems to be on the blood-vessels, perhaps irritating the endothelial wall of the capillaries, and thereby rendering it more permeable. This is particularly noticeable in muscles of the eye. The bundles and fibers of the muscles are separated more than is normal; the fibers of the connective tissue in these intennuscular spaces are slit apart and all these widened meshes and spaces are filled with fluid, which stains well with hematoxylin. The muscles are richly supplied with blood-capillaries which wind in and out about the muscle fibers. But we fail to see any lymph-capiUaries with a perceptible lumen; if they are present, as is to be presumed, they are at any rate not dilated. The muscles about the eye, like some muscles of the face, show a brown discoloration after diamine poisoning. It is an interesting observation that, while the anatomical and clinical effects of paraphenylendiamine are so widely different in the different species of animals, and even in animals of the same species, they all have one feature in common, viz., this brown discoloration of certain muscles of the face. Some of the writers who have studied the effect of this drug claim that the cause of the edema is to be sought for in the lacrmial gland. On the other hand, Puppe believes that the stasis edema is perhaps due to the formation of thrombi in the veins, and KunkeP also assigns to the blood-vessels and the blood a greater significance for the development of the intoxication edema. My observations agree with the latter view.
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On account of the extensive anastomoses of l>^nph-vessels obstruction to the outflow of lymph does not readily occur. We may conceive of the action of paraphenylendiamine as follows: in subcutaneous injections the drug enters the lymph channels, thence it is carried into the blood, where it irritates the walls of the blood-vessels, possibly having an injurious effect on the endothelial cells of the capillaries. Transudation of the plasma occurs very rapidly, the fluid filling all the tissue spaces and sep
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130 K.VETHK W. DEWEY
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arating the tissue elements. The function of the endothelial oell-^ of the lyniph-rapiilarios being not simply one of absorption of such free fluid, l)ut pr()bal)ly one of a selective action, of an interaction of metabolic processes, the fluid is not taken up and carried off rapidly enough with the result that stasis-edema develops.
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The formation of l>nnph is not, as was formerly believed, a mechanical process, i.e., one of simple filtration and diffusion, but is work essentially done by the organs themselves. The mechanical theory' has been sujierseded by the cellular-physiological theory. The endothelial cells of the lj'mph-cai)illaries probably play a chief part in these processes. Although these capillaries end or begin as absolutely closed culs-de-sac, and the presence of a continuous endothelium represents a barrier between them and the surrounding connective tissue, "the relations between the vascular cavity and the connect ive-t issue spaces renuiin very close," as Delaniere'" states, "anil cellular inunigration and osmotic exchanges may always take place and the capillaries fulfill their function of drains, and, if the observations of Renaut are conHrmed, may even act as selective drains."
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The value of i)araphenylendiamine in conjunction with vital staining is, in my opinion, this, that it illustrates and supports the theoiy of a difference between spaces filled with tissue fluids and real lymph-spaces and lymph-capillaries, which constitute the channels of origin of the lymph system. Bartels,' it is true, is rather skeptical as to any fruitful research along these lines. To him this nuich-debated (luestion is largely a philosophical one; he writes: The tiuestion concerning the origin of the lymph system and the development of the lymph stream from the flow of the tissue juices is a purely philosophical an<l not an anatomical one. This riuestion and that of the endings of the blood-vessels should be eliminated from anatomical discussions." Nevertheless, the contemporar>' conception of the origin of the lymph sy.stem is emphatic in uphohling the theorj' of an independence of the lymph-spaces and the tis.s\ie spaces, and of the absence of open communications between them, as also of a difference between plasma from the blood-capillaries and Ijmiph proper.
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LYMPHATIC SYSTEM OF THE EYE 131
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This fact is also illustrated by the observation that injections into the submucous cellular tissue of the skin may fill the tissue clefts and tissue spaces and produce edema, but not fill the lymphvessels. Similar observations may be made in injecting the blood-vessels with carmine gelatin; when the injection is continued under high pressure for some time, it may happen that the fluid portion of the injection mass is pressed through the stretched capillary wall and fills the tissue spaces producing edema without entering into lymph-vessels. In fact, I have never been able to fill lymph-vessels by way of the blood-vessels.
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As a result of my observations from the experiments which I have made, I have come to the conclusion that the vitally stained cells within the connective tissue of organs represent the endothelial cells lining the capillaries of origin. By several writers the view has been expressed that the connective tissue evidently plays a much more important role than that of being simply a supporting stroma for other parenchymatous tissue, and this impression is imparted to them chiefly by the presence of these peculiar vitally staining cells which have been called rhagiocrines, resting wandering cells, macrophages, pyrrol cells, histiogenic wandering cells, etc. The ability of these cells to take up the vital stain apparently coincides with specific functional properties; they ha-\'e chiefly been alleged with secretory functions, and Renaut" writes of the connective tissue as "the largest of the glands with an internal secretion which exists in the body of vertebras." On the other hand, Ehrlich points out the extraordinary adaptability of the cellular elements of this tissue and that a specific modification adjusted to definite functions of the organ which it supports, cannot be considered as in any way astonishing. But nowhere in the literature have I found even a suggestion that these specific cells may belong to the lymphatic apparatus. Yet we know that everywhere in the body the structures which constitute the beginning of the lymph system are embedded within the connective tissue. It is only reasonable to assume that the endothelial cells which form the sole wall of these delicate priniaiy lymph-channels (l>nnph-spaces and lymphcapillaries) are more than a lining; that they are rather the chief
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]^^2 KAETHE W. DEWEY
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agents in taking up the ambient tissue fluid or plasma from the bUxxl-rapillarics after it has been altered in its contact with the cells. This jirocess is more than one of simple filtration, or even of a selective filtration; it is a process of vital elaboration, including probably secretion and excretion. Furthermore, as the plasma differs from the lymjih partiallj' as a result of the activities of the l)l()<id-caiiillary endothelium, so, too, the Ij'Uiph coming from these capillaries is again modified when passing through the Ijniiph-gland ; for there are distinct differences in the lymph entering the lymph-gland and that passing out of the gland. The latter shows an increase in the cellular elements; the tendency to fibrin formation and coagulation is more rapid, and the proportion of the water is diminished. This modification of the lymph is likewise the work of the enilothelium of lymph-capillaries, for the lymph-vessels entering the lymph-gland break up into capillaries, thus forming a true portal lymph system. Bearing this in mind, it is most significant that this whole process of the fonnation of a second capillary network and of a modification of the lymph bj- its endothelium is signalized, as in the endothehum of the lymph-capillaries of the connective tissue, by the property of the cells to take up the vital stain. We have here, therefore, the striking phenomenon that at the source of the lymph system there are specifically functionating endothelial cells of capillaries, and that these alone have the power to take up the vital stain. This property is absent in the endothelial cells of the Ijnnph-vessels arising from the capillaries, but is present again, and in a most marked degree, in the endothelial cells of the capillaiy network within the lymph-gland; these are most brilliantly stained, while the afferents and the efferents of lymph-glands have no vitally staining endothelial cells. Evans" also has pointed this out as a voiy striking phenomenon.
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There are some other general observations on vital staining, agreeing well with anatomically established facts, to which I would call the attention. It is recognizeti that the lymphatics are unetiually distributed throughout the organism, seemingly in an arbitrarj' fashion. The same observation is made in regard to vitally stained cells. Lymph-vessels are considered to be
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LYMPHATIC SYSTEM OF THE EYE 133
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absent in a few organs and tissues; these are the same organs in which these cells are lacking. They are however, present in certain regions where lymph- vessels have not yet been demonstrated because of the almost unsurmountable difficulty in injecting them, but where they may reasonably be assumed to exist.
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The character of these cells has been interpreted variously; but the name of resting wandering cells seems to be the least fitting, for the most striking feature about them is the stability which characterizes their occurrence, their distribution, their arrangement, and their number. They are invariably absent or present in the same locality and invariably scanty or abundant in the same region. The constant recurrence of these features gives a strong unpression that these cells are stationary and that they are part of some definite, functionating apparatus. As to the eye, the occurrence of the same unequal distribution in the various tissues is striking.
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Schnaudigl'2 has studied the effect of vital staining on the eye and made observations concerning the occurrence of vitally stained cells which are on the whole in accordance with my own. They are as follows: the lens is devoid of vitally staining cells. No such cells are found in the cornea, but the conjunctival tissue overlying the corneal tissue shows such cells in large numbers. Occasionally a long, slender, vitally stained cell is seen to extend from the conjunctiva into the cornea. The sclera contains such cells in scant number; it is not quite clear whether they belong to the tissue proper or whether they accompany the vessels traversing the scleral tissue. The cells are quite numerous in the sclera and corneal conjunctiva and in great abundance in the limbus conjunctivae. The iris is very poorly provided with them; a cell is found here and there in the region toward the posterior chamber. This striking relative deficiency of the iris in vitally staining cells apparently was not noticed by Goldmann'^ who made the most extensive studies of vital staining with reference to internal and external secretions. But the statements of his findings in the eye are so brief that we hardly need discuss this difference in our observations. Assumhig that these cells denote the presence of lymph-capillaries, the extreme scarcity of such
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THE ANATOMICAL RECORD, VOL- 19, NO. 2
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l.M KAKTIIK \V. DKWr.Y
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chaniiols in an mnaii wliicli is well siip])lio(l with I )loocl- vessels is siii'prisiiin. for we may admit witli some of tlic best authorities in anatomy that lympii-vossels maj' be supposed to exist uliercvcr there are blood-vessels. This iinaeeountable scarcity of vital staining cells in the iris is the more striking because the region which adjoins it is unusually rich in vitally staining cells, namely, the ciliary body and chieMy the ciliary processes. The cells are in i)roportion more plentiful here tlum in any other part of the eye. They are arranged along the i)lood-vessels, from which, however, they are alwajs some distance removed. They are present in all the processes; they arealways in abundance and they are always arranged in the same way. When the injections of the staining fluid have been continued for some time these cells are very large and the gramiles are very coarse; in the iris or sclera they remain small and slend(M'. an observation to which also Sclmaudigl calls the attention. This author believes that these fells have an almost dangerous afiinity for the staining substance; they are very vulnerable and show the injurious effect of the dye after prolonged contact with the staining fluid. He also believes that this affinity for the dye correlat(>s to sjiecific functions and that these consist perhaps in more than the secretion of the aqueous humor. From the root of the ciliaiy jMocesses the cells are observed to occur in small number along the subjacent inner layer of the ciliary body; the deejier region, facing the sclera, is scantily supjilied with these cells and resembles the iris in this respect. In the choroid, cells are found chiefly in the choroio-capillaris. There are none in the retina. The endo- and perineural tissue contains vitally staineil cells. The loose orbital tissue is relatively poor in the.se cells. The muscles of the ej'c show the cells in the interfascicular and interfibrillar tissue, generally in the neighborhood of the blood-vessels. They seem to be in closer relationship to tlie i)lo()d-capillaries than, for example, in the ciliarj' processes; they often seem to spin around the capillaries while these agidn wind aiiout the muscle fil)ers. In the lacrimal gland they occur in the interacinous tissue and the connective ti.ssue surrounding the glandular structures. The lids and the nictitating membrane are well supplied with them ; they always
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LYMPHATIC SYSTEM OF THE EVE 135
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occur in the same arrang;einent and the same distribution. The cartilage is absolutely free from such cells.
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If we are to admit the view that these cells represent the endothelium of lymph-capillaries, we recognize that these findings corresi)ond quite well with what we actually know or may reasonably presume concerning the lymph supi)ly of the different parts of the eye.
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Until recently our knowledge of the hmiphatic sj'^stem of the eye as of that of the dental region was very limited. I will sum up the most essential anatomical data which enter into the frame of this study.
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The most important of recent work on the lymphatics of the eye is that of ^lost.'^ His results showed, in brief, the following: The conjunctiva of the lids and the eyeball contain very delicate l)ut dense networks of lymph-vessels. At the free border of the lids they pass over into those of the skin of the eyelid. The lymph-vessels from these two networks are divided into superficial and deep ones, chiefly according to whether they arise from the outer skin of the lid or from the conjunctiva; a sharp separation is not possible since both regions communicate with each other. The superficial vessels are apparently finer and less numerous; they course in front of the orbicularis muscle and in the superficial portions of the subcutaneous fatty tissue and only in the neighborhood of their regional glands do they pass into deeper regions. The deeper vessels form many anastomoses in the deep cellular tissue of the lids and then pass on peripherally behind the orbicularis muscle. The superficial as well as the deep vessels are divided into a lateral and a median set; they empty into the submaxillary lymph-glands.
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The superficial lateral ^•essels originate chiefly in tlie skin of nearly the entire upper lid and about the outer half of the lower lid. Their first and chief regional gland is a typical gland situated superficially in the parotitl gland at the level of the external auditory canal. From this gland vessels go to other deeper parotid lymph-glands. Only exceptionally do the superficial lymph-vessels empty directly into the deep nodes. One or two lymph-nodes situated at the lower parotid pole and belonging to
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13G KAKTIIK \V. DKWKY
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the group of the sviperficial cervical ^lantls are also to be considere<l as rcfiional glaiuls, because they may receive direct afferents from those regions of the eye.
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The deep lateral vessels arise in the conjunctiva of the upper lid and the outer third of the lower lid. The regional glands, besitles the superficial typical parotid lymph-nodes, include one or two nodes deeply emhedtlcd within the i)at()tid gland itself.
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The superficial median vessels arise chiefly in the skin of the inner half of the lower lid and that of the inner corner of the eye. Their regional gland is one of the submaxillary lymph-glands, especially that situated mesially of the anterior facial vein. The deep median vessels arise chiefly from the conjunctiva of the inner two-thirds and from the region of the caruncula. They form frequent anastomoses in the lid and pass along the anterior facial vein to the submaxillaiy glands and chiefly to a gland lateral to the one mentioned before. Sometimes this one is also injectetl. All these lym])h-vessels go secondarily to the deep cervical glands situated along the internal jugular vein, at the junction with the facial \ein. A direct connection of hniiphvessels of the lids and conjunctiva with these secondary glands could not be demonstrated, liefore the vessels of the lids aiui conjunctiva, and especially the median vessels, enter the parotid and submaxillaiy Ijnnjih-glands they may pass through intcrmediarj- Ij-mph-nodes of the face (lymphoglandulae i)uccales sive faciales) situated along the course of the anterior facial vein.
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The submaxillaiy lymjih-glands receive also the lymph from the outer vessels of the gingiva of the up])er and lower jaw, from the inner vessels of the lower jaw, and from the vessels of the peridental membrane of all teeth. No absolutely definite lines, however, can be drawn with regard to their relation to the different groups of teeth. For there are, on the one hand, variations in the number and location of the lymph-nodes themselves; on the other hand, it not infre(iuently happens that single lymph-vessels from a definite region |)ass by the regional node into which all the others enter and empty directly into a remoter lym])h-node. Another rea.son for this irregularity is the fact that the vessels from the gingiva form plexuses in the upper and lower mucosal
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LYMPHATIC SYSTEM OF THE EYE 137
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fold of the vestibulum oris, from which lymph-vessels pass out into the lymph-glands.
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An unportant path of communication between regions of the eye and the teeth is through the infra-orbital canal with its nerves, arteries, veins, and lymph-vessels. These send branches in either direction. Two small canals, the anterior and median alveolar canals, divide off directly from the infra-orbital canal and are continued as grooves within the wall of the antrum of Highmore. They transmit the corresponding nerves and bloodand lymph-vessels to the premolar, canine, and incisor teeth. The posterior alveolar canals, of which there are two or more, are continued from foramina on the infratemporal surface of the maxillary bone. They transmit the alveolar nerves and vessels to the molar teeth and also to the walls of the antrum. Within the wall of the maxillary bone all these canals form grooves rather than canals. Very little is known yet of the lymph-vessels of the accessory sinuses. Schweitzer'" states he obsei'ved that lymph-vessels from the maxillary sinus passed out of the infraorbital foramen and entered the submaxillary lymph-glands.
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In the endless contro^•ersies concerning the identity or difference of tissue spaces and true l>nnph spaces it has been customary to use the investigations of the cornea of the eye as the chief basis for discussions. The corneal spaces are not recognized now as lymph spaces. These and other spaces, like Tenon's space, the suprachoroidal space, spaces in joints and tendons, the endoand perilpnphatic spaces of the ear h&xe only a remote relationship to the lymph system; their functions differ in every case; frequently they serve only to fae-ilitate gliding motions and displacements necessary in the movements of the eye.
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The iris contains spaces filled with fluid, which communicate with the anterior chamber and with the spaces in the ligamentum pectinatum through the furrows or crypts on the anterior surface. These spaces in the iris are regarded as belonging to the lymph system.
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Cienuine hnnph- vessels have not been demonstrated either in the choroid or the sclera. According to Sattler, the veins of the vascular layer of the choroid are surroimded by perivascular
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13S KAETHE W. DEWEY
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sheaths, liiiod with eiulothi'lial cells. Toward the capillary layer, there exists, he believes, a eoiitimuius eiulothelial iiieinbrane which represents the liinitiiifi; iiieiiii)raiie of the vascular layer.
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There are no lymph-vessels in the retina.
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It has become customary to consider the ciliary body as the main source of the intra-ocular fluid (Leber," Wessely'*' '"). Hamburger-' ascribes also to the iris an important role in the function: in fact, he believes that every part of the eye participates in the secretion and resorption of the fluid, ^^'essely is of the opinion that it comes nearest to a transudate. It does not contain any substance which is foreign to blood-serum. There is, hence, no reason why we should not consider the process of its secretion as a filtration process. Some difficulties arise from the relatively high salt content and the involved greater o.smotic pressure, a property which it shares with the lymiih. The most striking difTerence is no doubt the low albvunen content which places it, on the one hand, in a class with the cerebrospinal fluid, the amniotic fluid, and the urine excreted in the glomeruli of the kidney, and, on the other hand, makes it stand in marked contrast to the lymph, ("ounterpressure to transudation may be the explanation: l)iit we are quite as well justified in supposing that the presence of a sjiecial epithelial layer which co\'ers the vessels may be the cau.se of the retention of the albumen. In the eye, the epithelium of the ciliaiy processes and the endothelium of the iris may act as such barriers.
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Schnaudigl'^ expresses the view that the vitally staining granular cells in the connective tissue of the ciliary body may be the chief agents in the secretion of the intra-ocular Huid. The epithelial cells covering the ciliary jirocesses remain colorless in injections of trypan blue, an observation which I also made with lithium cannine. It does not seem permissible to me to assume this specific function from the mere fact that these cells have a pronounced affinity for stains. For we nmst bear in mind that not only <lo vitally staining cells practically occur throughout the body in the connective tissue, but also tiiat in\ariably they are larger and more coarsely granular in definite regions of the body, for example, in the pia of the brain, where they occur in patches,
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LYMPHATIC SYSTEM OF THE EYE 130
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in the choi'oid ])loxus. in certain regions of the nasal ajiparatus. On the other hand, there are cells admittedl}^ endowed with secretory functions, cells other than those within the connective tissue, which also have a pronounced affinity for vital stains (the epithelial cells of the choroid plexus, in the hypophysis, the thyroid glantl, the sj^ncytial cells of the placenta, the epithelial cells of the convoluted tubules of the kidney), while other cells of a similar type are not stained by trj'pan blue or carmine. I am more inclined to believe that, inasmuch as these particular vitally staining cells occur practically every^vhere in the connective tissue, they have everywhere the same function to perform and, inasmuch as in some localities they are invariably more intenselj' stained, they are involved either more intensely in the same process or in another associated function. Along this line of reasoning we may also assume that the function of lymph secretion or lymph resorption is associated with the secretion of a fluid related to IjTiiph, such as the cerebrospinal fluid, the intra-ocular fluid, or even the chyle. From this standpoint the great scarcity and smaller size of A'italh' staining cells in the iris would speak against the view of some writers that the iris is notably involved in the secretion of the aqueous humor, while the presence of a large number of intensely staining granular cells in the ciliary body support the more generally accepted theory that these are the main source of the intra-ocular fluid. On the other hand, there is nothing in my ^•iew of the part which the vitally staining cells play in the lymi^hatic apparatus that would contradict the view expressed by Hamburger that there is a more active resorption of the fluid by the iris through Ijnnphchannels than the generally assumed venous drainage into the canal of Schlemm. The fluid has a direct entrance into the iris through the crypts and thence into the lymph-vessels. According to mj^ observation, lymph-channels which simply convey lymph have no vitally staining endothelial cells. This might explain the curious fact that there are so few of such cells in the iris, especially in the anterior portion. As to the drainage mto the canal of Schlemm, Hamburger states, that the resorption through the spaces of Fontana may also be along perivascular lymph-spaces and not by the l)lood-\essels.
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140 KAETHE W, DEWEY
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lUnLIOGRAPIIY
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1 Dewey, Kaethe, and Noyes, F. B. 1917 A study of the lymphatic vessels
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of the dental p\ilp. Dental Cosmos, vol. oS, p. 436.
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2 XovES, F. B., AND Dewey, Kaetiie lOlS The lymphatics of the dental
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region. .lourn. .\m. Mod. .Xs.-*., vol. 71, p. 1171).
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3 Bautei.s, r. I'.KH) Das Lymi>hKi'fasssy.stom. S. 50. Jena.
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4 BiKCii-HiKsriiFELD, A. I'JO'J Die Krankheitcn der Orbita. Graefe-Sac misch Hnndbuch der gesamten Augenheilkunde, 107-170 Licferung.
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S. 201. a GRrxERT. K. liX).3 Die Augensyniptome bei Vergiftung niit Paraphenylen diamin ncbst Bemerkungen iibcr die Ili.stologie derTriinendriise. Ber.
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iiber d. 31, Vers. d. Ophth. Gescll.s., S. 20S. M.\TsrMOTo, H. 1901 Ucber die Giftwirkiing dps Paraphenylendiamins.
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Wiirzbiirg, I. D.
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7 PcPPE, G. 1S90 I'eber Paraphcnylendiaiiiin Vergiftung. Vicrteljahrs schr. f. geriehtl.Med., 3. Folge, Bd. 12, Siipplenirritsheft,.'^. 110 (quoted by Matsumoto).
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8 Dewey, Kaethe 1918 A contribution to the study of the iiathways of the
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cerebro.s|)inal fluid and the choroid plextis. Anat. Rec, vol. 15, p. 1. KuNKEL, .\. J. I'.Wl Handbueh der Toxikologie. S. 610. Jena.
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10 Delamere, (!. 1904 The Lymphatics: Chicago. 71 (translated from Poirier
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and Char|)ey by Leaf).
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11 Resaut 1907 Les cellules connectices rhagiocrines. .\rch. d'anat. micro scop., vol. 9, p. 495.
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12 Evans, H. M. 1915 The macrophages of manmials. .\iii. Jnurn. of Phys.,
 +
 +
vol. 37, p. -242.
 +
 +
13 ScilNAUDluL, O. 1913 Die vitale Fiirbung uiit Tryi)anblau am .\uge. .Vrch.
 +
 +
f. Ophthalm., vol. 80, p. 93. 11 GoLDMANN, K 1909, 1912 Die iiusserc und innere Sekretion des gesunden
 +
 +
und kranken Organismus im Lichte vitaler Fiirbung. Beitr. z. klin.
 +
 +
Chir., Bd. .54, S. 192, and Bd. 78, S. 1. 15 Most, \. 1905 Ueber die Lyin|)hgefasse und die regioniiren Lymphdriisen
 +
 +
der Bindehaut und der Lidor des Aiiges. Arch. f. .\nat. u. Physiol.,
 +
 +
.'Vnatomical part, ]). 90. 10 Schweitzer, li. liX)7, 1909 Ucber die Lymphgefiisse des Zahnflei.sches und
 +
 +
der Ziihne beim Menschen und bei Siiugeticren. Arch. f. mikrosk.
 +
 +
Anat. u. Entwickl., Bd. 09, S. 807; ibid., Bd. 74, S. 927. 17 Quoted by KoELi.iKER, .\. 1902 Handbuch der Gewebelehre des Men.schen,
 +
 +
Gefiisssystem. Bd. 3, S. GC5. Leipzig. IS Leher. T. 1913 Die Cirkidations- >ind Krnahningsverli:'iltnis.sp des Auges.
 +
 +
Graefe-.Saemi8ch Ilandbucli <ler ges. .Vugeidieilk., Bd. 2, 2. Aufl.
 +
 +
19 Wk.smely, K. 1905 Der Fliissigkcils- und ,'^lolTwecli.sel iles .\ugcs niit be sonderer Beriicksichtigung seiner Bc/iehungen zu allgemein i)hysiologischen und biologischeii Fragen. Krg. d. I'hys., Wiesb., Bd. 4, S. 505.
 +
 +
20 1908 Experimentelle I'ntersuchungen iiber den Augendruck, sowie iiber qualitative und quantitative Beeinflussung des intraokularen FlO.ssigkeitswechsels. Arch. f. Augenheilk., Bd. 00, i*^. 97.
 +
 +
21 Hamiiu RGER, C. 1914 Ueber die Erniihrung des Auges. Leipzig.
 +
 +
 +
 +
PLATE
 +
 +
 +
 +
141
 +
 +
 +
 +
PLATE 1
 +
 +
EXPLANATION OF FIGURES
 +
 +
1 Ui-trobulbar muscle tissue, stained with hematoxylin, a, blood-capillary windiiiK about a musdo fiber; h, vitally stained pranular endothelial cell, presumably of the linin)! of a lymph-vessel with collapsed walls; c, blood-capillarj' with two nuclei and separated blood-corpuscles, illustrating how the walls collapse as those of the lyni|)h-capillaries, when no corpuscular elements hold them apart .
 +
 +
2 Cross-section I hroURh the ciliary body, sclera, and conjunctiva. Unstained. a, large granular endothelial cells in the ciliary processes ;fc, smaller cells at the base of the processes; r, fewer slender cells in the outer third of the sclera. There are none in the inner two-thirds of the scleral tissue; (/, numerous larger cells in the conjunctiva.
 +
 +
3 Longitudinal section of a ciliary process. Stained lightly with hematoxylin, o, e))itlielial cells; h, blood-vessels; r, large granula cells.
 +
 +
 +
 +
142
 +
 +
 +
 +
LYMPHATIC SYSTEM OF THE EYE
 +
 +
KAETHE W. DEWEY
 +
 +
 +
 +
PLATE 1
 +
 +
 +
 +
 +
 +
 +
 +
ft
 +
 +
 +
 +
 +
 +
 +
i* . ^
 +
 +
 +
 +
I.
 +
 +
 +
 +
 +
 +
143
 +
 +
 +
 +
Resunien por el autor, Ralph A. Kordenat, T'nivcrsidad de Illinois.
 +
 +
Contaniinaci6n de los cadaveres por cl Saccharomyces eerevisiae.
 +
 +
El crcoiinicnto do honRos sobre los cadaveres es causa de considerable i)erdida lie material en los laljoratorios anat6niicos. El presente trabajo da a conocer la existencia de tal contamiiiari6n. Vn estudio de los caracteres de los ciiltivos de dichos bongos, sus propiedadcs de coloraci6n, niorfologia y experinientos sobre aniinales, denuiestran que esta "levadura" es una variedad no pat6gena y saprofitica del Saccharoniyces eerevisiae. Vn estudio de varios gei'iiiieidas y antisepticos doiiiostr6 que el creciiiiiento de estos bongos se inii)ide enibalsainaudo los cadaveres con la siguiente f6rmula: Olicerina, 300 cc; forniol, 400 cc; alcohol, 1000 CO.; fenol, 90 granios; agua, 400 cc. Primero se us6 el bicloruro de niercurio (1)0 granios), pero despu^s se on)iti6 su enijjleo jiorcjuc forma un codgulo resistente y granular en los vasos sanguineos, cjue impide la penetraei6n completa del liquido embalsamador. y. adenuis, por el coste de dicha substancia quiniica. Su presencia en el cadaver no es necesaria para imi)edir el crecimiento del bongo. Como medida profilactica panos mojados en la siguiente soluci6n, con los {{ue se envuelven loscuerpos, imj)iden el crecimiento de la levadura asi como la desecaci6n y endurecimiento rajjiilos de los nn'isculos expuestos. La soluciAn se compone de: (llicerina, 50 cc.; fenol, 2 grainos; alcohol. ')() cc; agua (que se anadini) 1000 cc.
 +
 +
Tmnalatiun hy J(W- K. Xunidd Cornell Univcraity Mwlifal Collrar, N. Y.
 +
 +
 +
 +
author's abstract op this papkh issued by the didliographic aicuvice, may 24
 +
 +
 +
 +
CONTAMINATION OF CADAVERS BY SACCHAROMYCES CEREVISIAE
 +
 +
RALPH A. KORDENAT
 +
 +
Departments of Bacteriology and Anatomy, University of Illinois College of Medicine, Chicago, Illinois
 +
 +
TWO FICnBES
 +
 +
Recently the cadavers in the anatomical laboratories of the University of Illinois, College of JNIedicine, became covered by a moist, slimy, slightlj^ elevated growth that has caused no small amount of trouble and annoyance. The growth is dirty gray in color, loosely adherent, and does not penetrate the deeper tissues. It has never been noticed upon the unbroken skin of the cadaver; when the skin is remo\Td, however, the growth begins and spreads with great rapidity, making dissection of the specimen out of the ciuestion and causing great waste of material.
 +
 +
A quantity of this grayish substance was taken to the bacteriological laboratory for examination. Smears showed a large number of highly refractive, o\-oid cells, measuring about 7fx in diameter. In addition to these, there were large numbers of bacteria, especially staphjiococci.
 +
 +
It seemed plain that the slimy growth was largely made up of the above-mentioned ovoid cells, and cidtiu'es were therefore made in order to isolate and study them in detail.
 +
 +
After several attempts, pure cultures of the organism in question were obtained.
 +
 +
CULTURAL CHARACTERISTICS
 +
 +
Neutral plain agar. After twenty-foiu' hours' incubation at 37°C. small, round, bluish-gray colonies, about the size of a pinhead were seen. Their margins were smooth and regular. After an additional twentj'-four hours' incubation at room temperature
 +
 +
145
 +
 +
 +
 +
14li RALPH A. KORDENAT
 +
 +
these colonies turned white in color, l)iit did not increase in size or nunihor.
 +
 +
Fiiv per cent dcxtrnsc, agar. Twentj'-four-hour culures showed a growth similar ti> that on plain agar. After another twentyfour hours at room tcmjioraturo they were much larger and creamy white in color, becoming confluent in most cases so as to cover the entire surface of the media. The characteristic odor of 'yeast' was noticed.
 +
 +
Plain broth. The growth in jilain broth was not profuse. There was a slight flocculent sediment at the end of twentj-four hours. The broth was slightly turbid.
 +
 +
Fii<c per cent dextrose broth. The growth was similar to that in plain broth, but more pronounced; a heavy sediment and the characteristic odor of yeast.
 +
 +
Litmus milk. A marked acid production at the end of fortyeight hours with coagulation; the curd in most cases being completely digesteil, leaving a whitish turbid whey.
 +
 +
Gelatin stabs, (ielatin-stab cultures showed only a slight growth upon the surface, resembling that on jilain agar. No liquefaction.
 +
 +
The organism ferments glucose with the formation of carbon dioxide and alcohol.
 +
 +
ST.\INING PROPERTIES
 +
 +
Tiic organism stains fairly well with the oriiinary dyes and exceptionally well bj^ the Gram method, being strongly Grampositive (figs. 1 and 2). When stained by \\'right's stain, a welldefined blue cell membrane is seen with ])al(' lijue mitochondria and numerous vacuoles within.
 +
 +
iMOlU'IIOLOGY
 +
 +
The organisms average about 7 ix in diameter and are round to ovoid in form. In a hanging-drop preparation of a forty-eighthour culture, a highly refractive, non-motile, double-contoured cell is seen in an active state of bud<ling. The budding generally takes place from the long end of the ovoid cells. The younger
 +
 +
 +
 +
CONTAMINATION OF CADAVERS 147
 +
 +
cells are small and more rounded in form, while the older cells, from which the budding takes place, are more elongated. There is no tendency to form mycelia.
 +
 +
A pure known culture of Saccharomyces cerevisiae was comjiarcd with the organism taken from the cadaver, and it was found that in every way the two resembled each other in morphology, staining properties, and in general cultural characteristics.
 +
 +
 +
 +
4
 +
 +
 +
 +
 +
 +
I 2.
 +
 +
Fig. 1 Strain 'A.' Saccharomyces cerevisiae from cadaver. Gram's stain (X1200).
 +
 +
Fig. 2 Strain 'B.' Known pure culture of Saccharomyces cerevisiae. Gram's stain (X1200).
 +
 +
ANIMAL EXPERIMENTS
 +
 +
White mice, after being inoculated with rather large doses of a normal salt suspension of the organism, showed no ill effects.
 +
 +
An effort was made to reproduce the growth upon animals. Two dead rabbits, with the skin and viscera removed, were immersed in the embalming fluiil used for the preparation of the bodies in the anatomical laboratories. This embalming fluid consists of —
 +
 +
 +
 +
MS UALl'll A. KOUUENAT
 +
 +
Ctlyccrin 300 cc.
 +
 +
Koniitilin 400 cc.
 +
 +
Alcohol 1000 cc.
 +
 +
Phenol 45 grnni.s
 +
 +
Water 400 cc.
 +
 +
.\ftor a iicriod of diic wock they wore removed and a pure culture (if the cadaver orfiaiiisni planted upon one an<l a ))ure known culture of Saccharoniyees cere\isiac i)lantcd upon the other. At the end of three days the entire bodies of the two rabbits were .similarly covered with a slimy, grayish film. Two days later this growth became a dirty, creamy white and resembled that found u])on the cailavers. Thus, it is further evident that the two organisms are alike.
 +
 +
TIIEUMAL DKATII POINT
 +
 +
A series of small test-tubes, each containing 2 cc. of a suspension of the cadaver culture (strain 'A') and a known strain of Saccharoniyees cerevisiae (strain 'B') were used. At the different degrees of temperature indicated in the table, tubes of each of the two organisms were placed in a water-bath for a i)eri()d of ten minutes, allowing one minute for the temperature of the tubes to reach that of the water-bath. The tubes were then removed and per cent dextrose-agar slants inoculated and incubated. The results are given in the table. Both organisms were killed at 58°C'. for ten minutes, Init not at 5(i°(". for ten minutes.
 +
 +
Because of the apparent identity of the cultural characteristics and staining properties, as well as the results of the animal ex])erinients with the organisms, it is further evident that the contamination of the cadavers is a strain of Saccharoniyees cerevisiae.
 +
 +
I have been able to find nothing in the literature concerning the contamination of cada\"ers by Saccharoniyees cere\isiae. In a personal communication fir)Mi Dr. Irving Hardestj% of Tulanc I'niversity, he states that he has had a similar experience with 'molds,' that the mold thrives on formalin-hanlened bodies, that alcohol favors its growth, and that carlxilic acid will not check it unless the bodies are completely immersed in the carbolic solution.
 +
 +
 +
 +
CONTAMINATION OF CADAVERS
 +
 +
 +
 +
149
 +
 +
 +
 +
In order to find some disinfectant for this organism that might be effective in embalming fluids, the following experiments were performed :
 +
 +
The carbolic coefficients for potassium chromate, formalin, and mercuric bichloride were determined according to the method advocated by the U. S. P. H. S. (Hygienic Laboratory Bulletin no. 82) and further described by M. J. Rosenau in his test on "Preventive Medicine and Hygiene." Instead, however, of finding the coefficient with the use of a twenty-four hour culture of tj^phoid bacillus, forty-eight hour cultures of the two strains of
 +
 +
TABLE 1 Thermal death point
 +
 +
 +
 +
temperatdhe (10-mindte exposure)
 +
 +
 +
STRAIN 'a' growth
 +
 +
 +
STRAIN 'b' growth
 +
 +
 +
°C.
 +
 +
 +
 +
 +
 +
 +
48
 +
 +
 +
Positive
 +
 +
 +
Positive
 +
 +
 +
50
 +
 +
 +
Positive
 +
 +
 +
Positive
 +
 +
 +
52
 +
 +
 +
Positive
 +
 +
 +
Positive
 +
 +
 +
56
 +
 +
 +
Positive
 +
 +
 +
Positive
 +
 +
 +
58
 +
 +
 +
Negative
 +
 +
 +
Negative
 +
 +
 +
62
 +
 +
 +
Negative
 +
 +
 +
Negative
 +
 +
 +
64
 +
 +
 +
Negative
 +
 +
 +
Negative
 +
 +
 +
68
 +
 +
 +
Negative
 +
 +
 +
Negative
 +
 +
 +
70
 +
 +
 +
Negative
 +
 +
 +
Negative
 +
 +
 +
72
 +
 +
 +
Negative
 +
 +
 +
Negative
 +
 +
 +
74
 +
 +
 +
Negative
 +
 +
 +
Negative
 +
 +
 +
78
 +
 +
 +
Negative
 +
 +
 +
Negative
 +
 +
 +
 +
Saccharomyces cerevisiae were used, because the yeast is in its most active state of budding at that time. It was found, by determining the carbolic coefficient, that phenol is the most efficient disinfectant for these yeasts. The action of mercuric bichloride toward these organisms is too inconstant for one to reach any definite conclusion as to its use. Formalin and potassiimi chromate have too low a coefficient to be of any value.
 +
 +
The prevention of this growth was now attempted bj^ altering the composition of the embalming fluid previously used. A rabbit was embalmed with the following fluid:
 +
 +
 +
 +
THE ANATOMICAI^ RECORD, VOL. 19, NO. 2
 +
 +
 +
 +
150 RALPH A. KORDENAT
 +
 +
Glycerin 300 cc.
 +
 +
Formalin 400 cc.
 +
 +
Alcohol 1000 cc.
 +
 +
I'lipnnl 90 Rram?
 +
 +
Mercuric bichloride 90 grnms
 +
 +
Water 400 cc.
 +
 +
It will be seen that this solution differs from the one previously mentioned in that the phenol is doubled and mercuric bichloride is added. The rabbit was immersed in the same solution for three days, seeded with cultures of both yeasts, and then covered with moist towels. \i the end of four days there was no growth. It was considered inadvisable to include mercuric bichloride in the embalming fluid not only because of the extra expense, but because there is a granular coagulation of the blood in the small vessels. This firm, granular coaguliun completely obstructs the smaller vessels, thus preventing the thorough penetration of the solution. Other rabbits, embalmed with the same fluid minus the mercuric bichloride, were seeded with both strains of the yeast and incubated for four days. These also showed no growth.
 +
 +
.\n examination was made of the dust taken from the floor, walls, and tables of the anatomical laboratory. Some of this dust was taken up by means of a sterile cotton swab and 5 per cent dextrose broth and agar inoculated and then incubated for twenty-four hours at room temperature. Many of the samples revealed Saccharomyces cerevisiae.
 +
 +
.\s a prophylactic measure, cloth was soaked with the following solution:
 +
 +
Glycerin 50 cc.
 +
 +
Phenol 2 grams
 +
 +
Alcohol 50 cc.
 +
 +
Water (q. 8. ad) 1000 cc.
 +
 +
and was draped over one-half of the bodies in the laboratory (group A) at the end of each dissection for a period of four months. The other half of the cadavers (group 1^) served as a control. During these four months none of the l)odies of group A was affected, while six of the bodies of group B became covered with the growth.
 +
 +
 +
 +
CONTAMINATION OF CADAVERS 151
 +
 +
By applying the above solution upon the embalmed bodies, the specimens are not only protected from the yeast but the glycerin keeps the exposed muscles more soft and pliable.
 +
 +
CONCLUSIONS
 +
 +
Because of the apparent identity of the cultural characteristics, morphology, staining properties, and of the animal experiments mentioned, it is concluded that the organism in question is a saprophytic strain of Saccharomyces cerevisiae.
 +
 +
The growth of Saccharomyces cerevisiae upon anatomical specimens renders them useless, thereby causing great waste of material.
 +
 +
Phenol is the most efficient disinfectant for this particular strain of yeast.
 +
 +
The contamination can be prevented by using the embalming fluids and the prophylactic measures mentioned.
 +
 +
The use of mercuric bichloride in embalming fluids is not practical; first, because it forms a firm granular coagulum of blood in the vessels, thus preventing the complete penetration of the fluid, and, second, because of the expense of the chemical. The prophylactic measures indicated not only protect the cadavers from the Saccharomyces cerevisiae, but prevent rapid drying and hardening of the exposed muscles.
 +
 +
 +
 +
1*3
 +
 +
 +
 +
THE AXATOMIC.VL RECORD, VOL. 19, NO. 3
 +
 +
ACGCST, 1920
 +
 +
 +
 +
Abstracted by E. D. Congdon, author. Loland Stanford .luiiior T'liivorsity.
 +
 +
Simultaneous occurrence of very small sphenoid and frontal
 +
 +
sinuses.
 +
 +
Because of the uncertainty as to the reason for failure or incompleteness of sinus development, the present almost unique instance of very rudimentary condititm of four siiuises merits description. The sphenoid sinuses were symmetrical in form and position. They were about 4 nun. in sagittal and 14 mm. in craniocaudal diameter. A lateral extension of the cavity brought each into series with the corresponding posterior ethmoid cells. The ostium of the left sinus was so far forward antl so lateral as to almost justify the interjiretation that it was an ethmoid cell. The ostium region on the other side was destroyed. The cavity interpreted as the left frontal sinus was so small that it is not certain that it extended beyond the ethmoid bone. There was no especial condensation of compact bone to warrant the supposition that, the sinuses may have been hindered in their development l\v infantile disease. It is possible that tlie sphenoid sinuses are to be grouped with others previously described by the writer which were apparently unable to exjiand through material of the concha-presphenoid fusion plane. Xo compen.^ation for the loss of these cavities was noticeable in the size of the other sinuses.
 +
 +
 +
 +
ATTHOR 8 ABSTRACT OF THIS PAPER ISSUED BY THK BIBLIOGRAPHIC SERVICE, JUNE 21
 +
 +
 +
 +
SIMULTANEOUS OCCURRENCE OF VERY S^VIALL SPHENOID AND FRONTAL SINUSES
 +
 +
E. D. CONGDON
 +
 +
TWO FIGURES
 +
 +
A few very small sphenoid sinuses have been recorded, and complete absence has been claimed bj' several observers. Incomplete de\-elopment and absence of frontal sinuses are both rather frequent. Only one previous record was found of the slight development of sinuses of two types in the same individual. This also had to do with the frontal and sphenoid cavities. I'hey were described by Wertheim ('01) in an eight-year-old child. The observation was made for a sufficiently early stage of development to admit of the possibility that the deficiency would have been made good to a considerable degree before adult life.
 +
 +
The explanations which have been advanced for the absence and incomplete development of the sinuses are at present supjjorted by little e^•idence. Information regarding the paranasal region needs to be collected in these cases if any explanation is to become more than a hypothesis. Although it is especially desirable that this be obtained for foetal and infantile specimens, since observations on such material will of necessity be rather infrequent, the conditions surrounding absence or incomplete development of adult sinuses should be examined for whatever information it can afford.
 +
 +
The rudimentary sinuses were found in the course of dissection and were preserved with the mucoperiosteum nearly intact. The subject was an adult male apparently of European parentage. The small spherical cavities were symmetricallj' developed and extended to the orbit behind the last posterior ethmoid cell (fig. 1). The anteroposterior diameter of the portion Ij'ing within the area usually ascribed to the sphenoid was 4 mm. and its height 14 mm. upon the right and 12 nun. upon the left side.
 +
 +
153
 +
 +
 +
 +
154
 +
 +
 +
 +
E. D. CONGDON
 +
 +
 +
 +
The ostium of the left sinus opened l):ick\vard, although it was so far lateral as to l)e little posterior to the nearest ethmoid cell. Were it not for the position of the aperture, the sinus could as well be classified as a posterior ethmoid cell with a recess in the sphenoid bone, because the |)art of the cavity in series with the ethmoid cells has a position frec[ucntly occupied by one of them, and the most posterior ethmoid cell also not rarely invades the supero-anterior part of the sphenoid where the median portions of these sinuses were located.
 +
 +
 +
 +
 +
Fig. I Parasagittal diagrammatic drawing through left sphenoid sinus (a). Three posterii)r ethmoid cells as (6) represented by dash lines. .A. fourth, the most posterior which had been oi)ened in dissection outlined in an unbroken line. Above it the aperture of the sphenoid sinus also shown by an unbroken line.
 +
 +
 +
 +
The portion of the wall of the right sphenoid sinus corresponding to the aperture of the left is not jierforated and no comnumication of the sinus on this side with the nasal cavity occurs elsewhere. .V saw cut has destroyed that part of the wall lying a little more medially. Either the aperture niust have been situated in this region then or the sinus lacked an outlet. There ha.s been considerable discussion as to whether this second alternative ever occurs. Some authors categorically deny that a sinus can originate without an opening, since they believe sinus fonnation is always by the out-pocketing of the nasal cavity. Zuckerkandl ('93) states that he has seen two sphenoid sinuses
 +
 +
 +
 +
VERY SMALL SPHENOID AND FROXTAL SINUSES
 +
 +
 +
 +
155
 +
 +
 +
 +
without apci'tures in their bony walls. No other record of the lack of opening to the osseous wall of a s}:)henoid sinus was found. Evidently its absence is very rare, although closure of the aperture by the swelling of the mucosa is frequent. P"or this reason and because the closely similar companion sinus had an opening, it is very probable that its aperture was destroyed by the saw.
 +
 +
 +
 +
 +
Fig. 2 Right frontal sinus lo). X 1.
 +
 +
 +
 +
The more rudimentary of the two frontal sinuses is shown in figure 2. There is a marked difference in the frequencies of absence of the frontal sinus as given by various authors. Onodi ('11) places it as high as 20 per cent, while Boege (,"02) finds it. to be only 4.9 per cent. Much of this tliscrepancy is probably due to different conceptions of what constitutes the earliest developmental stage of a frontal sinus as contrasted with a beginning ethmoid cell. The recess (fig. 2, a) is here regarded as a frontal sinus because it is already separated by a ridge from another division of the frontal recess and is in the ])roper position
 +
 +
 +
 +
1")() K. n. roNGDON'
 +
 +
to ciilarfio directly iiitu the i'rontiil bono. It is the passage into till' frniital hoiii' u|u>ii wliiih the aijplicatioii of tlip toiiii frontal to a siiiii^ should depend, liut it is u-iiaiiy not practieal)le, even if it is not impossible, to determine wlietlier small out-pocketiuKs of the frontal recess have passed beyond tlie confines of th(> ethmoid bone or not.
 +
 +
No peculiarities were observed in the other paranasal sinuses which could aid in lindinii the reason for the ruilimentary condition of the fr<intal and sphenoid sinuses. '1 he sponj^y bone surrounding the four sinuses was .-itjuiewliat more dense than the average. It may be, therefore, that foetal or infantile disease may have broniiht about a condition which interfered with the enlarfienient of the sinuses. Onodi (11) and Wertheini COl) have broufiht tofjether some eviilence of such an occurrence. The condensation of the spoiio:y bone was not extreme, and, since there was no atiophy of the nuicosa. the arjiument for (>arly disease is not convincinji. Furthermore, it would be surprising that sinuses at opjiosite ends of the nasal cavity should be affected while the maxillary and ethmoid sinuses opeiiinu: at iiiterjnediate positions are normally developed.
 +
 +
'riie explanation hrst suggesteil by Toldt "SSi for the origin of the bony plates in the s])henoid sinus and further elaborated by Cope ("17) and the writer ('!!•) may possibly be apjilicable also to the retardation of the sphenoid sinuses. Toldt regarded the planes and ridges as the renniant of material at the plane of fusion of the adjacent ossification centers of the sphenoid sinus which was able to re>ist the absorptive action of the periosteum during the enlargement of the simis.
 +
 +
Seven sphenoid sinuses out of two Innidred and forty two were found by the writer ('1'.)) whose posterior walls corresponded in position and direction with the usual i)lane of fusion of conchal and ]>resphenoid centers. This let! to the sviggestion that resistant material had prevented the e.vtension of (he sinus backwaril The two rudimentary sinuses Ikmc imder discussion lia\e jiosterior walls lying more anteriorly and somewhat more transversely than the usual position of the plane. It may be that in this instance a plane situated especially far anteriorly i)ut .in early stop to the backwaril extension of the sinuses.
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 +
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VERY SMALL SPHENOID AND FRONTAL SINUSES 157
 +
 +
The incomplete development of the two pairs of sinuses in the same individual is suggestive of a correlation between the development of the two tj'pes. The interrelation of form and size of adult sinuses seems to show that alternative correlation is a common feature of sinus development when one of two adjacent sinuses succeeds in preempting space originally open to both and thus brings about the underdevelopment of its neighbor. The suggestion has also been made that as an adaptation to keep the total sinus space up to the usual amount the underdevelopment of some sinuses might be correlated with an unusually extensive growth of others through some unknown mechanism. As far as could be found, there is no evidence for the occurrence of a growth response of this nature. If there is a correlation which explains the concurrent retardation of development of the four sinuses in the specimen which has been described, it differs in type from the relationship just referred to in that the sinuses all vary from the norm in the same dkection. The retardation or absence of two frontal sinuses is so often bilateral as to be probably correlated. Less data are at hand for sphenoid sinuses, though a certain degree of correlation is probable. The retardation of development of frontal and sphenoid sinuses in the same head is so rare that its coexistence in the two types is probably a matter of chance.
 +
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LITERATURE CITED
 +
 +
BoEGE, K. 1902 Zur Anatomie der Stirnhohlen. Inaug. Diss., Konigsberg. CoNGDON, E. D. 1919 The distribution and significance of septa in the sphenoid
 +
 +
sinus. Cope, V. Z. 1917 The internal structureof the sphenoid sinus. Jour, of Anat.,
 +
 +
vol.51. Crter, M. H. 1916 The internal anatomy of the face. Philadelphia and
 +
 +
New York. Onodi, a. 1911 Die Nebenhohlen der Nase beim Kinde. Wlirzburg. ToLDT, C. 18S3 Osteologische Mittheilungen. Ztsch. f. Heilkuiule, Bd. 4. Wertheim, E. 1901 Beitrage zur Patliologie und Klinik der Erkrankungen der
 +
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Nasen nebenhohlen. .\rch. f. Laryngol., Bd. 11. ZucKERKANDL. E. 1S93 Xomiale und pathulogischc .Vnatomie der Xasenhohle
 +
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und ihrer pneumatisohen .-Vnhange. Bd. 1, Zweitc .Vufl., Wicn und
 +
 +
Leipzig.
 +
 +
 +
 +
Abstracted by E. D. Congdon, author. Lelaiid Stanford Junior University.
 +
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Anomalous fibrous cords in the hand and the phylogeny of the flexor digit orum sublimis tendon.
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The fibrous cords are evidently renuiants of the ancestral short flexor muscles of the hand which are normally represented by the distal part of the flexor digitorum sublimis tendons, according to Eisler's theory. Thej' were attached proxiinally on the radial sides of the bases of the proximal jihalangos of the fourth and fifth digits and extended distally to bifurcate like the flexor digitorum sublimis tendons and insert on either side of the volar surface of the middle phalanx. The coexistence of the cores with normal flexor digitorum sublimis tendons apparently either contradicts this interpretation or disproves the theor3\ Also Bardelebon and Kajava state that the flexor digitorum sublimis tendon may exist side by side with the short musculature in certain mammals, and Fromont describes an anomaly in the human hand showing this condition. Since there are compelling reasons both from comi)arative anatomy and embryology for Eisler's theor>% it is proi>able that in these apparently contradictory instances the rudiments of the short flexors split to go only in part to the sul)limis tendon, while the rest was retained to form more or less jierfect short superficial flexor niusdes.
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ACTHOB 8 ABSTRACT OF THIS PAPER ISSUED BY THE BIBUOGR.U>HIC SERVICE, JUNE 21
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ANOMALOUS FIBROUS CORDS IN THE HAND AND THE PHYLOGENY OF THE FLEXOR DIGITORUIM SUBLIMIS TENDON
 +
 +
E. D. CONGDON
 +
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TWO FIGURES
 +
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Tendon-like cords were found in one hand of an aged male subject during the course of dissection by Mr. A. F. Warren. They lie upon the volar sides of the fourth and fifth fingers of the right hand and are closely similar in form and position (fig. 1). Each extends distally from an attachment on the radial side of the base of the proximal phalanx to the volar surface of the vaginal ligaments and there bifurcates. The slips thus formed pass to the opposite sides of the middle phalanx to insert into the vagmal ligament the adjacent fascia and the border of the dorsal extensor aponeurosis. Although of a somewhat less compact structure than a tendon, they can by no means be described as mere condensations of fascia. They did not bring about any marked flexion of the digits in the cadaver, and probably did not hamper movement during life.
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The muscles to which the cords seem related are the short superficial digital flexors of amphibia, reptiles, and mammals. These take origin usually upon or in the volar fascia and have insertion in part at least by a pair of slips upon the sides of the metacarpo-phalangeal joint or more distally. The cords differ from the muscles in the position of their proximal ends. Instead of passing to the palmar aponeurosis along the mid-line of the digit they are deflected to the side of the base of the proximal phalanx. The dissimilarity is not great, however, because the cords are in continuity on the phalangeal bases with slips of insertion of the palmar aponeurosis. The relationship of the cords are not like those of the lumbricales or interossei, nor are either of these muscles abnormal or lacking.
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159
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100 E. D. CONGDON
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The presence of ten short digital flexors in urodele amphibians, in nionotremcs, and marsupials is gonerally accepted as sufficient reason for regartling the structures as an anccstraf muscle for mar. and other mammals possessing the flexor digitorum sublimis muscle. .\s will be seen Testut and Fromont have also described the primitive short superficial flexors in the adult human hand. It can be accepted with a large degree of confidence then that the anomalies in question are actual short superficial flexor remnants.
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Fig. 1 Hand (after Fromont, with parts omitted) showing abnormal digital muscles, a.a, tendon of flexor digitorum sublimis upon which are inserted muscles (e.e), interpreted here as short superficial digital flexors; 6.6, muscles interpreted as short superficial digital flexors taking the place of tendons of flexor digitorum sublimis. X i.
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The flexor digitorum sublimis muscles of man and many mammals said to arise in part from the short superficial flexor muscles lie in large part within the fore arm, but send their tendons through the palm to the digits. Here they bifurcate to insert on cither side of the second phalanx. The flexor digitorum profundus, a companion nmsdc, whose muscle belly is also in the arm, inserts on the distal phalanges by tendons which pass between the bifurcations of the subHmis insertion. Eisler ('95) suggested that the tenninal portion of the sublimis tendon with its bifurcated insertion might be notfiing else than a degnerated superficial flexor muscle which after having changed completely to tendon had come, by means of its attachment to the palmar
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ANOMALOUS I IBROUS CORDS IX HAND IGl
 +
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aponeurosis, to be continuous with a part of the fore arm flexor mass which earlier inserted on the palmar aponeurosis.
 +
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McMurrich's careful study of the flexor muscles of amphibians, reptiles, and mammals ('03) gave confirmation and amplification to Eisler's suggestion. It received support of another kind when (iriifenberg COo) found that a short flexor musculature in the hand of the himian embryo connected with a fore arm mass to form a flexor sublimis.
 +
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With this view of the origin of the flexor digitorum sublimis muscle it is not to be expected that any manmudian finger will possess at the same time one of its tendons and a short superficial flexor muscle. Kajava ('11) who has examined the digital flexor musculature of monotremes and eleven species of marsupials foiuid, as did McMurrich for other animals, that the two never occurretl together in the same digit. Yet Kajava states that there are certain insectivora and carnivora which do possess both the flexor superficialis brevis and the sublimis; Bardeleben ('90) much earlier made a like claim for Hyrax and, according to Eisler (95), for Paradoxurus.
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 +
References bj' two authors to aberrant muscles of the human hantl related to the anomaly here described bring confirmation to the theory of end-to-end fusion for the sublimis, but at the same time in part offer difficulties similar to those found by Kajava and Bardeleben. Testut is quoted by Kajava from a work which was not accessible as giving instances of the occurrence of a short flexor in the hvunan hand for the little finger which had replaced the corresponding sublimis tendon.
 +
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Fromont found a similar displacement of the flexor sublimis in two digits of the hand. His figure is copied here (fig. 2b). A better confirmation of the theory of end-to-end fusion bj' a reappearance of the primitive structures could scarcely be desired. The condition of the musculature of two other digits were found however to be more invoKed, the flexor sublimis was jiresent in each of them, l)ut theie W(>re also other slender nuiscle bellies taking origin from the trans\ersc carpal ligament, and inserting on the sublimis tendons (fig. 2a). The conclusion seems necessary that in these two digits part of the embryonic
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1(12
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K. I). CUNUUUX
 +
 +
 +
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lutlimont derived from the ancestral short flexor ha\e given rise to tlie correspondiiifi niuscles in the aihiit. The rehitionships and origin of these slender nuiseles are also like those of the two larger short sviperlicial flexors. Froniont terms the two of the four short muscles which insert on the suhlimis tendons sujierHcial hnnhricals, but likelihood of identitj- with Umibricals is excluded by their relationships and by the presence of almost normal lumbricals in the usual position in the digits to which thev are related.
 +
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 +
 +
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Fig. 2 Fourth ;in(l liftli digits of loft hsuul witli tendinous cords (a.a) apparently representing remnants of short superficiiil digital flexors. X J.
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It has been seen that llic instances of abnormal human nuiscular development described by Testut, Fromont, and the writer confirm the comparative anatomical evidence taken from a wide field by Kisler, McMmrich, anil Kajava for the theory of end-toend fusion to the extent that they reveal a tendency toward the formation of short suiierficial digital flexors in man. But at the .same time the anomalies of Fromont and the writer present a difficulty for the theoiy in the simultaneous occurrence of the short superficial flexors and the tendons which are .supposed to arise fro:n them. Observations of a like condition in the
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ANOMALOUS FIBROUS CORDS IN HAND 103
 +
 +
normal structure of a few other mammals have already been referred to. A possible explanation of this contradiction is that when muscle and tendon appear together, the short flexor rudiment divided at an early developmental period to give rise to both the muscle and the tendon. The supposition that there were paired short superficial flexors in the human ancestry as in some other mammals and that their rudiments give origin one to the muscle and one to the tendon is not probable because of the rarity of the anomaly.
 +
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BIBLIOGRAPHY
 +
 +
Bardeleben, Karl v. 1S90 Uber die Hand- und Fuss-Muskeln der Saugetiere, besonders die des PraepoUex (Praehallux) und Postrainimus. Anat. Anz., Bd. 5.
 +
 +
Fisher, P. 189.5 Die Flexores digitorum. Verhand. Anat. Gesell., .\nat. Anz., Bd. 10.
 +
 +
Fromont 189.5 Anomalies musculaires multiples de la main. Absence du fl^chisseur propre du pouce. .Absence des muscles de I'eminence thenar. Lombricaux suppl^mentaires. Bulletins de la Societe anatomique de Paris, 5"" S6rie, T. 9.
 +
 +
Gr.Kfexberg, E. 1905 Die Entwickelung der Knochen, Muskeln und Xerven der Hand und der flir die Bewegungen der Hand bestimmten Muskeln des Untcrarmes. Anat. Hefte, erste Abt., Bd. 30.
 +
 +
Kajava, Y. 1911 Die kurzen Muskeln und die langen Beugemuskelu der Saugetierhand. I. jSIonotremata und Marsupiala. Vergleichendanatomische Untersuchungen. Anat. Hefte, erste Abt., Bd. 42.
 +
 +
McMuKKiCH 1903 The phylogeny of the palmar musculature. Am. Jour. Anat., vol. 2.
 +
 +
 +
 +
Abstracted by E. D. roiipdoii, author. Leland Stanford .Iiininr I'niversity.
 +
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Acquired skeletal deformities in a young fowl.
 +
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A young cockerel reared in an incubator till about three months of age showcil marked skeletal deformities which were in part mechanical efifects of confinement under a roof with which the bird gradually came in contact as it increased in height. The dorsoventral thoracic diameter was reduced a half. The tnmk anterior and posterior to the interacetabular line was bent downward. Apparently the down thrust of the neck against the thorax, due to the striking of the hea<l against the roof, together with the downward pull of the leg muscles upon the posterior portion of the trunk in the effort to keep the body from falling forward were responsible for the bend. There was marked underdevelopment and further deformity of the trunk skeleton. The cervical vertebral column approached adult size, but was retarded in differentiation. The wattles, comb, and beak showed a difTerentiation tyi)ical of a larger cockerel. The gross apjiearance of the trunk skeleton suggested that the cockerel may have had rickets. No microscopic examination was made. The only indication of poor health which was noted was a ruffling of the plumage for a few days before the animal was killed.
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ACQUIRED SKELETAL DEFORIMITIES IN A YOUXG
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FOWL
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E. D. COXGDON Leland Stanford Junior University
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SIX FIGURES
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Two young cockerels reared in an incubator showed skeletal deformities approaching in degree the effects of a severe case of human rachitis. Although the influence of mechanical conditions upon the form of the mammalian and especially the human osseous system has long been studied, no descriptions were found in the literature of marked deformities in the domestic fowl or any other bird.
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At the time when it was noticed that the chicks had been kept too long in the incubator, their backs were already in contact with the ceiling. As thej'^ grew, their heads must have been gradually' forced to a lower level relative to the rest of the body.
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The cockerels evidenced poor health bj' a ruffling of their plumage (fig. 1), and they were somewhat sluggish in their movements. There is little doubt that the direct mechanical effects due to unusual posture and contact of the head with the roof were complicated by the influence of the other unfavorable conditions, such as high temperature and lack of exercise. It may be that the slight thickening at costochondral junctions and at the posterior ends of the uncinates, the bending of certain bones and other disturbances of growth, which will be described, are due in part to rickets and osteomalacia. Insufficient attention was given to the question before the skeleton was cleaned to answer the question. Tripier' tried the effect of diet with lowprotein content and containing little earth salts upon two young pullets, and described a change in the physical properties of their
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' Arch, de Physiol, norm, ct pathol. (2) 1, 1S74.
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16.5
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 +
IGO K. D. CONGDON
 +
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bones. He diil not mention, however, any change in skeletal projiortions or in the shape of the individual bones. » The larger and more deformed of the two fowl was used for a detailed examination of the skeleton. Two cockerels were chosen for comparison, one of these showed less maturity than the abnormal bird in comb, wattles, and bill, but was of nearly the same length and height. The other was chosen because the comb, wattles, and bill indicated an equal maturity. It was nuich larger than the abnormal fowl, though it was of average size in comparison with other normal cockerels in the same stage of development. The controls and deformed bird were all White Leghorn stock of ajipro-ximately pure breed.
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Figures 2 to (i show the abnormal and the smaller control birds under equal magnification. The trunk of the abnormal cockerel is the smaller, although, as will be later seen, it would probably have been as large or larger had it developed normally. Some features of its deformity come out strikingly in the profile view with the trunk musculature in position (figs. 2 and .3). The thoracic region has a dorsal and a ventral diameter about half that of the smaller control. The posterior portion of the trunk is also somewhat smaller. \ comparison of figures 2 and 4 shows that incomplete development of the breast muscle and sternal keel ])la}' a consiilerable part in the thoracic reduction, though the body cavity in this region is also disproportionately small in cross-section in comparison with the parts external to the trunk.
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The chief skeletal malformation which can be readily traced to a mechanical cause consists of a bending downward of the anterior and posterior portions of the trunk, so that their longitudinal axes meet at a slight angle at a transverse i)lane passing through the hip-joint. The pelvic bones are correspondingl}bent at their acetabuli and the sternum at the junction of the cartilaginous and bony portions of the keel. This condition evidentlj' develoijcd as an effect of the frequent down thrust of head and neck upon the thorax, when the head came in contact with the roof as the chicken tried to assume an erect posture. To retain the balance of the body upon the legs at the acetabuli.
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SKELETAL DEFORMITIES IN A YOUNG FOWL 107
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Fig. 1 Abnormal cockerel
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Fig. 2 Abnormal cockerel
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Fig. 3 Younger control cockerel. Magnification the same as in figure 2
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Fig. 4 Abnormal cockerel.
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THE ANATOMICAL Ri:i.ORD, VOL. 19, N0.3
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KiS K. n. CONGDON
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when the (lowiiwanl iiiipulso was (■oiiuminiratod hv the nock to till" thorax, the musculature from tin- lcfj;s to the part of the i)elvis postpiior to the acetuluilar joints must have contracted with more tlian ordinary vi^or. The two unusually powerful downward forces acting at opjHtsite ends of the trunk resulted in the hendinjj at the interacetahular transverse i)lane.
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The trunk skeleton shows abnormalities throughout that may not he so directly connected with mechanical influences as is the hentling of the tnmk. The ribs ami uncinat(>s are thicker relative to their length than in the conlml liirds. The ends of the costal and sternal ribs, which articulate witli one another, and the posterior ends of the uncinates are enlarged. The disproportion of the trunk relative to the neck is shown in the vertebral column 1)\- a tlecrease in size of the successive dorsal vertebrae posterior to tlic siHDud. in place of the u>ual increase in their dimension.s.
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The ossa coxae are not only bent, but are narrower than usual in conformity with the diminished diameter of the entire trunk relative to its length. The bend in the body of the .sternum has alreatly been mentioned. Its bony keel is of only half the usual dorsoventral extent at its posterior end, and decreases to an inconsiderable ridge anteri(»rly. The reduction of the keel is probably ilue in large part to the direct elTect of striking the breast against the bottom of the incubator, when as frequently happened, the down thrust of the neck at the thorax caused the animal to topjjlc forward after pushing its head against the roof. It is not prol)able that undenlcxclopmenl of the bivast muscle had much, if anything, to do with lack of develoj)ment of the keel, becau.se other bones as.sociated with these muscles including the coracoid furcula and body of the sternum, if of less than the usual size, are certainly much nearer to the norm than is the keel. The furcula which extends downward from the superior extremity of the coracoid to the antero-inferir)r angle of the keel has undergone a reduction in length coiiesponding to the decrease in the dorsoventral extent of the keel.
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SKELETAL DEFORMITIES IN A YOUNG FOWL 169
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There are details in the form of the skull which may be due to the repeated striking and pressure of the head against the roof. It should be stated, howexer, that these do not greatly exceed in amount the normal variation as shown in the skulls of four other cockerels of about the same age. The frontal region of the skull seems to have been pushed slightly forward and down (fig. 0). The weilge-shaped projection of the cranial cavitj- Ij'ing between the upper and posterior portions of the orbits is enlarged at their expense, so that the orbital processes of the frontal bone are unusually conspicious in a lateral view of the skull. The anterosuperior orbital region which usually has a nearly straight edge is convex and flares upward, as though the ej^eball had been pushed forward against it. A protrusion of the e^^eball was not looked for while the animal was ali\e and it was not noticed. In the photographs of figure 2 and 4 it appears to be present. • The comb is bent over as if from frequent contact with the roof, yet its deformity cannot be assigned to this cause with certaintj', because lopped combs are not rare among \Miite Leghorns.
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Other gross malformations of the osseous sj^stem not directly traceable to the effects of pressui'c of the head against the roof manifest themselves both in the form and in the size of the bones. The ribs, uncinates, coracoid, furcula, and cervical vertebrae are. thicker and more rounded than in the controls. The pelvic l)ones and sternum are so irregular in form that they mask any abnormalitj- of a like nature, which may have been present. The surface markings of scapula, coracoid, furcula, sternum, cervical vertebrae, ribs, and imcinates are less sharply defined than in the control skeletons. The characteristics of form both as regards general outline and detail consist in a retention of an earlier developmental condition modified perhaps bj^ other pathological characters.
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^'arious parts of the skeleton show irregularities in relati\e \(ilunie, some of which have been already mentioned. Though the retardation of the trunk is so marked that it can scarcely be questioned, the less marked differences of relative size in
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170
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K. D. CONfJDON
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Fig. 5 Viiungor CKiiIri)! cockert,-!. Magnirication the same as in figure 4 I'"ig. 6 A. Skull and a portion of cervical vertebral rolunin of younger control eockerel. H. Skull and upper part of cervical vertebral C'>lunwi of aluiorinal cockerel.
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SKELETAL DEFORMITIES IN A YOUNG • FOWL
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171
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other regions make it difficult to decide which if any of these have normal measurements. The wattles, comb, and bill indicate maturity equal to the older control bird, whose body is twice as large as that of the abnormal cockerel, and was chosen from a number of equal maturity as representing their average size. Since the skull of the deformed bird appears to be normal except for the deformity due to pressure against the roof and is of almost the same length as the control, it may be the birds would have been of equal size as well as maturity, had conditions been normal. The measurements of the skeleton of the extremity are unfortunately limited to the femur and the coracoid. Both agree closely in length with the smaller control. The appearance of the extremities in figures 2 and 3 confirm this view. The only careful observations of the bone form in these regions were upon the tibiofemoral joint. Here no retardation of development could be noticed.
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Comparative measurements of abnormal cockerel, large and small control and rooster
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ife
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Q
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AVERAGE ME.ASCBE
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J
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=: X
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n
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00 «
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CEBTICAL VERTE
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« <
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Q
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BRAL COLUMN
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Q IS
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Z
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5.
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S £ 2
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b.
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& 5
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s
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•^o'
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m
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S
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P
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■SB
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o •- S »
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a ■
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■g o d o
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C
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»j
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m .
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cm.
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cm.
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cm.
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cm.
 +
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cm.
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cm.
 +
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Abnormal cockerel
 +
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11.5 12.0
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 +
 +
6.7 6.5
 +
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6 7 6.7
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 +
0.98 0.91
 +
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0.62 0.54
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1.24
 +
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Younger control (10 months old) .
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1.15
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Older control (13 months old). . . .
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14
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6.8^
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10.1
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0.93
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0.54
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1.10
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 +
Rooster
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20.0
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8.0
 +
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13.6
 +
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1.27
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 +
 +
0.61
 +
 +
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1.49
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The cervical column has plainly undergone an excessive development in volume, since, as seen in the accompanying table, it is not only larger than the older control in three measurements which were chosen, but it even slightly exceeds a rooster in the minimmn transverse diameter of its centrum. The upper vertebrae are especial!}' large and the atlas largest of all (fig. 6.) These facts together with the correspondence, of the limb skeleton in
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17:
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E. D. CONGDON
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loiigtli with the smaller fowl and its lack of abnormal characters Iciui some support to the view that the youiiKPr control may represent the true size of the deformed l)ird, had it developed normally and that there has been an overgrowth of skull as well as cervical vertebral column. The less sharply sculptured surface and the more massive form is found in the cervical column, which has been freipiently describetl in other instances of overgrowth. The skull did not show a sunilar condition, but its comparative freedom from surface elevations would prevent easy recognition of a slight deficiency in this respect.
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Abstracted by FrancLs Marsh Baldwin, author. Iowa State College.
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Notes on the branches of the aorta farcus aortae) and the subclavian artery of the rabbit.
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.Vlthough the usual number of blood-vessels arising from the aorta in the rabbit is two- a so-called innominate or brachiocephalic and the left subclavian arteries- the variation from this condition herein described indicates the possibility of a considerable (leiiarturc. Of* 10() sjiecimens, about 20 i)er cent differed from what is usually considered normal, either in respect to the aortic vessels or the subclavian arteries of either side. In one individual a single vessel leaves the arch of the aorta, and after passing forward subsecpiently successively subdivided to form the left subclavian, the left common carotid, and the innominate or brachiocephalic arteries. When three vessels originate on the arch, they are usually the innominate and the two carotids, although in one ca.se the vertebral of one side contributed to this arrangement in the place of a carotid. Several individuals .show conditions suggestive of four vessels, comprising the two carotids, the left vertebral and left subclavian. The order and secjuential differences of vessels from the subclavian arteries of each side are noted.
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AtTTHOR'B ABSTRACT OF THIS PAPER ISSUED BY THE BIBLIOGRAPHIC SERVICE, JCNE 21
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NOTES ON THE BRANCHES OF THE AORTA (.\RCUS
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AORTAE) AND THE SUBCLA^TAN ARTERY
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OF THE RABBIT
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FRANCIS MARSH BALDWIN Iowa Stale College, Department of Zoology, Ames, Iowa
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ELEVEN FIGURES (OXE PLATE)
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Bensley,' in his Practical Anatomy of the Rabbit (p. 3C5), in discussing the blood-vessels of the thorax, describes the arch of the
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aorta as "beginning at the bast of the heart, passes
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forward, and then describing a curve, in the course of which it lies slightlj' to the left of the median plane, turns backward along the ventral surfaces of the bodies of the thoracic vertebrae. VCith the exception of the coronary arteries the first branches are the large paired vessels arising from the anterior wall. They comprise the common carotid and subclavian arteries. On the right side the carotid and subclavian arise from a. short common trunk, the innominate arter}^ The left common carotid arises inunediately to the left of this vessel or from its base. The subclavian artery (a. subclavia) is the first portion of the artery of the antei'ior limb. It passes from its point of origin laterad to the anterior margin of the first rib, where it is replaced bj' the axillary arter3\ Near its point of origin, it gives off several branches, the relations of which are subject to considerable variation."
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The large pah-ed vessels referred to above is not exact and leads to confusion, since even in the usual condition it applies to neither the right and left common carotid arteries, nor the paired subclavian arteries, but to an innominate artery on the right side, and the left subclavian artery on the other. That the left common carotid artery usually arises immediately to the left
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17:5
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174 FRANCIS MARSH RALDWIX
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of the base of tho innominate is perhaps correct, although in by far tho greater minihor of rabbits dissected the origin of this vessel is well up on the mesal side of the innominate. In cases where the left common carotid artery arises to the left of the innominate, there would be three vessels arising from the cephalic curve of the aorta and not two (a pair) as above described, a condition normally found in the human, ^^'ith reference to the subclavian arteries, the statement as to their branches being subject to, considerable variation, is correct, but it seems important that the point should also be made, that great differences occur in these vessels on the right and left sitles in the same animal.
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.\gain, Parker and Haswell- describe correctly the relation of these vessels as they occur in the majority of cases, but the figure shown (p. 4()5) represents the condition in an abnormal individual, where the left common carotid artep' originates as a branch from the arch of the aorta, and thus constitutes the third vessel from the arch, the innominate and the left subclavian being the other two. Since these discrepancies exist in the descrii)tions of the blood-vessels of the region in the various texts, and in view of the variability of both the arteries given off by the arch of the aorta, anil their subseciuent subdivisions, especially those of the subclavian, it seems of sufficient interest to record their frequency and extent. Accordingly, the following description is based upon the study of over one hundred sj)ecimens. Such records, of course, have no immediate practical value from the surgical or pathological sides, but from the educational considerations, es|)ecially from the standjioint of comparative anatomy they are rather imjiortant. No doul)t the variations which are described below are to be explained in part by the persistence of foetal conditions, or in some cases bj' abnormalities of the vessels themselves, or to the development of extrinsic parts in their immeiliatc region. Many of the changes brought about are probably due to different modes of transformation of the primary vessels of the branchial arches, especially the fourth, since the aorta as well as the pulmonary artery are derivatives of this arch, .\gain, it is well known that the heart itself originally develops high up in the neck region of mammals, and is
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AORTA AXD SUBCLAVIAN ARTERIES OF THE RABBIT 175
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gradually shifted downward, so that this gradual shifting might account for some of the variations noted.
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Of one hundred and six rabbits dissected* nineteen individuals showed marked variations from the usual condition, either in the branches from the aorta, or in respect to the subclavian and its branches in either side. There were others (fifteen) which showed minor variations, but which could easily be placed in some of those showing marked variations, so that their condition is represented, j^artially at least, in some one or in a composite of the subjoined figures.
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In what may be termed the usual condition, the aorta (fig. 1, A), after giving off the coronary arteries close to its junction with the left ventricle, passes cephalad a short distance, and then describes a curve of a half circle and passes down the back, a little to the left of the ventral vertebrae. From the cephalic curve (arch) a comparatively large innominate or brachiocephalic arterj' extends upward and a little to the right and soon bifurcates, forming the left common carotid artery which passes immediately across the trachea to the left side of the neck, and a common trunk which gives rise to the right subclavian and the right common carotid arteries. A second branch from the curve of the aorta is the left subclavian artery which passes laterad and forward to branch in \'arious ways. Usually on this side the superior intercostal (costocervical) (fig. 1,/) is the first branch to be given ofi", and passes caudomediad. Just distal in close jimcture with the superior intercostal artery is the internal mammary artery, while just opposite arises the vertebral artery. Distally the subclavian artery soon divides into the transverse scapular (T) and the axillary (X) arteries. On the right side the superior intercostal and mannnary arteries arise from a common trunk, as also do the vertebral and transverse scapular arteries just opposite to them. The axillarj^ artery passes to the region of the forearm. In some cases the superficial cervical artery branches from the subclavian, but usually it is a branch of the transverse artery of either side.
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.My thanks are duo Mi'. Ralph L. Parker, my assistant, for aid in dissection.
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17() FRANCIS MARSH BALDWIN
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VARIATIONS OF THE SUBCLAVIAN ARTERY OF THE LEFT SIDE
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A mimlier of interesting variations are noted in the order and sequential relationships of the various vessels arising from the left subclavian. Fre(iuently the arteries originating from the subclavian arterj' in close proximity to each other so that a veritable corona of the vessels is formed. In some cases, as shown in figures and 11, this takes p\aco at ([uite a distance from the arch of the aorta, and can be called the long corona type, while in others, tj-pified in figures 9 and 10 and perhaps less conspicuously in figure 8, the corona formation is closely approximated to the aortic arch, ^^'here the corona is formed, the usual order of the vessels may be described as normal, i.e., beginning with the vertebral arteiy originating on the cephalomesal siu'face of the subclavian, the transverse scapular, axillaiy, mammarj-, and intercostal arteries followed in the cycle clockwise. Tn one specimen an interesting departure is noted, in that the intercostal artery (fig. 6, 7) takes its origin from the vertebral so that there is formed in this case a veiy short innominate with the vertebral artery. A number of cases are observed where the intercostal and mammary arteries formed a short innominate in common as is shown in figures 4 and 7. In one rabbit (fig. 3 V) the vertebral artery of this side branches from the cephalic surface of the arch of the aorta at about its junction with the subclavian artery, and in this case it is comparatively a much larger vessel than normal. In this specimen also the transverse scapular and manunary arteries have their origin some distance cephalad, and the interval between the intercostal and manunary arteries is verj- noticeable. In no case is there found an iimominatc formed by the left subclavian and the left common carotid arteries, which of course is the typical avian condition, and which has been described to occur in most apes, and somewhat more rarely has been noted in the human. In three cases, however, varying in degrees, as shown in figures G, 8, and 10, the left conmion carotid artery is a separate branch from the arch of the aorta, and in these the condition closely simulates the normal condition found in the human. In one in
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AOUTA AND SUBCLAVIAN ARTERIES Ol- THE RABBIT 177
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stance the points of origin of the vertebral and the transverse scapuhir arteries are interchanged, as shown in figure 2, and in another, figure 5, the vertebral artery arises from the laterocaudal surface of the subclavian in the same manner but distal to the intercostal and mannnary arteries, and then turns niesal to enter the transverse foramina of the cervical vertebrae. In the last specimen also a number of excessory blood-vessels are noted, some of which parallel the mammaiy, others the intercostal arteries.
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THE SUBCLAVIAN ARTERY OF THE RIGHT SIDE
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The blood-vessels of this side which take their origin from the subclavian arterj' seem less variable in their relationships than those just described. There is the formation of what may be termed a corona in several instances, but this is with but one exception formed relatively close to the innominate, or to that portion close to the bifurcation of the innominate which forms the subclavian and right carotid arteries. Such a condition is typically shown in figure 5, where the vessels spread out in fanshape formation about the subclavian. In one instance, the vertebral artery (fig. 2, V) originates well cephalad and on the lateral surface of the right common carotid artery, so that its displacement from its usual position is rather striking. As regards the interrelation of the intercostal and internal mannnary arteries, all sorts of gradations of intervals exist from the formation of a conspicuous elongated innominate, as is indicated in figure 3, or a much-reduced innominate, as shown in figure 11, to the more or less widely separated intervals, as rejiresented in figures 8 and 9. Ihe intercostal artery in the last case is really a branch of the innominate, and has no connection with the sul)clavian. I'sually the superficial cervical arterj' of this side as in the normal condition is a branch of the transverse scapular artery, but in two cases it is greatly displaced; one originating fiom the subclavian (fig. 3) and another curiously entering the conunon jimction of the intercostal-mannnary vessels, as shown in figure 10. In one case the transverse scapular artery originates as a branch of the vertebral well cephalad of the latter's
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178 FRANCIS MARSH BALDWIN
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junction witli the snl)clavian, as in fiRiiio S, altlioufih in Iwo other siK'cinions this condition is hardy suggested in the close proximity of the origins of the two vessels, as in figure 9.
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The manner of hrancliing of tlie two carotid arteries from the innominate is of interest, although not more variable than might he expected. In the majority of specimens showing differences in other respects, the two carotid arteries hranch well up on the innominate. In several cases the point of origin of the left common carotid artery is close to the curve of the aorta, and in three cases (figs. 0, 8, and 10) the junction is really on the arch, thus giving rise to an adilitional vessel in these cases, as indicated ahove, which sinuilates very closely that found normally in the human. Three individuals (figs. 7, 1), and 10) show the formation of a thyreoitl ima, so-called, a small vessel arising on the innominate hetween the right and left common carotid arteries, which passes forward to the thyreoid glanil anil gives off small vessels to the neck nniscles of the region and to the trachea. Its ])oint of origin varies somewhat in the three animals, but morjjhologically it bears the same jiosition as has been described for a similar vessel in the human (]\Ic]Murrich.' p. 511.), i.e., it pa.sses f«)rward from the innominate between the common carotid arteries of either side. It should he said, however, that since the common carotiilsof either side in man ditTer slightly in their jxiints of origin from those in the rabbit, the formation of this vessel in the rabbit does not contributeto the format ion of a fourth vessel arising from the ;.rch of the aorta, as is the case in man, I ut does form a fourth vessel from the innominate. Inasingleca.><e, as .shown in figure 11, the arch of the aorta gives rise to but one vessel, an innominate, which passes ce|)hala(l for some distance before it breaks to form, first, the left subclavian, anil a little further forward the left common carotid artery, and the brachiocephalic artery. This jjeculiar variation is interesting, since it closely simulates the normal condition found in the horse. It may be exi)laincd by the fusion of the two aortic .stems and the .shortening of the fourth arch so that the left subclavian arterj* joins with the common stem during the transformation of the i)rimary vessels. In one instance the left vertebral i^fig. 3, V) takes its origin well
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AORTA AND SUBCLAVIAN ARTERIES OF THE RABBIT 179
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(low 11 on the left subclavian vessel so that it is almost in a position to be considered a sej^arate branch from the arch of the aorta and could be interpreted as an additional vessel from the latter as has been recorded as a variation in the human (Mc^Iurrich, p. 511). It is e&sy to see how by a slight displacement caudad of the left common carotid artery in this case would produce four distinct vessels originating from the arch of the aorta instead of the usual two.
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SUMMARY
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Although the usual number of blood-vessels arising from the arch of the aorta in tlie ral)bit is two — a so-called innominate or brachiocephalic artery and a left subclavian artery — the variations from this condition herein described indicate the possibility of a considerable departure. In one individual (fig. 11) a single vessel leaves the aortic arch, and after passing a short distance forward subdivides successively to form the left subclavian, the left common carotid, and the innominate or brachiocephalic arteries, the latter subdividing again to form the right common carotid and the right subclavian arteries.
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In a number of cases, as shown in figures 6, 8 and 10, three vessels have their origin on the arch, and in these the order is the brachiocephalic, the left common carotid, and the left subclavian arteries. In one individual (fig. '.i) the left vertebral replaces the left conmion carotid artery in the series, the carotid in this case having its orgin on the innomhiate as normally. This case suggests the possibility of four vessels forming the series.
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Conspicuous differences in the order and sequence of the vessels from the subclavian arteries of the two sides are noted. On the left side the vessels in a number of cases show a tendency to group themselves either proximally or distally in the form of a short corona, as indicated in figures 6, 9 and 10. The formation of various innominate stalks common to certain arteries are found in some cases, while in others the intervals between certain arteries are rather noticeable. Less marked variations are noted in the vessels of the right side. The vertcliral artery in
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ISO FRANCIS MARSH BALDWIN
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ono iiistanco (Tip. 2") is (lis])hifO(l from its usual plarp to the lateral side of the right coininon carotid artery. The transverse scapular artery in two eases is a branch of the vertel)ral, while the superhcial cervical, which is normally a branch of the transverse scapular, in one case (fifi. 10 ) leaves the subclavian as a commnn stalk with the intercostal and mammary arteries.
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In three cases a small so-called thyreoid ima is present, and in these this passes forward from its origin between the two common carotids, thus having the same morjjhological jKisition in the rabbits as a similarly described vessel occupies hi the human.
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LITERATURK CITED
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1 IU:\si.KY, B. A. lOl.S Pmotical anatomy of the rabbit, 2nd edition, pp.
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■_'.')(>-2.')". I'niv. Toronto Press. '2 I'ARKKn AND Haswell I9I0 Text-book of zoology, 2n(l edition, vol. 2, pp.
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•lGl-tG.5. .MacMillan Co. 3 McMruiiicii, .1. P. 1906 Morris's human anatomy, tth edition, pp. 510-511 ;
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5.56. P. Blakiston's Sons & Co., Phila.
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AORTA AND SUBCLAVIAN ARTERIES OF THE RABBIT 181 PLATE 1
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EXPLANATION OF FIGURES
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1 Diagrammatic ventral view of the arteries of the thoracic region of the rabbit, showing the various branches as they occur in the majority of specimens. The innominate (brachiocephalic) (N) and the left subclavian (S) are the two usual branches of the arch of the aorta. The left subclavian gives origin to a number of arteries as here shown, while the innominate bifurcates to form the two common carotids and the right subclavian arteries.
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2 Schematic ventral view of the arterfes of rabbit 32, which conspicuously indicates the vertebral artery of the right side as a branch of the right carotid artery. Notice on the left side the transverse scapular and the vertebral arteries are morphologically interposed and the intercostal and mammary arteries are separated by quite an interval. The left common carotid is well down at the base of the innominate, almost constituting a separate branch of the arch of the aorta.
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3 Ventral view of the arteries in rabbit 40. The vertebral artery of the left side is here formed close to the junction of the subclavian with the aortic arch, and thus forms what may be considered a third branch of the arch. The intercostal and mammary arteries of the left side are separated bj' a wide interval.
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4 Rabbit 53 shows the formation of common stalks (innominates) for the intercostal and mammary arteries of both sides as well as the transverse and superficial cervical of the right. The brachiocephalic gives rise immediately to the left common carotid.
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5 The arteries of rabbit 22 show differences in branches of the right and left subclavian vessels especially. The intercostal and mammary arteries originate separately on the right, the vertebral on the left is well cephalad of the other vessels, and makes a bend caudomesad as here shown. Accessory vessels are found on the left sitle also.
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6 In rabbit 28 the formation of what may be termed a long corona of the left subclavian with a migration of the intercostal from the lateral surface of the subclavian to form a common stalk with the vertebral artery. The left common carotid artery is here a branch of the aortic arch so that three distinct branches are formed. The innominate is conspicuously long.
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7 Specimen 19 shows among other variations the formation of the thyreoid ima, a small vessel originating on the innominate just caudad to the point of origin of the left common carotid artery and passing forward to the thyreoid gland of the neck.
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8 Rabbit 21 shows interesting relationships of the innominate, left common carotid, and left subclavian arteries, and shows the comparatively immediate subdivision of the subclavian of either side. Such a condition may be designated as the short corona type.
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9 Specimen 106 shows the so-called thyreoid ima and other minor variations especially in the interval between the intercostal and mammary arteries of the right side, and the formation of the short corona type of the left subclavian artery.
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THE ANATOMICAL RECORD, VOL. 19, NO. 3
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IS-j
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FUANCIS MARSH BALDWIN'
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10 In riil)bit 85, beside the thyreoid itiiii heiii); present, the left subclavian takes its origin on the arch and the superficial cervical of the right side passes out friini tlie common stalk of the intercostomamraary artery. The subclavian of the left side forms a short corona.
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11 In rabbit 52 the innominate (brachiocephalic) artery is the only vessel originating on the arch of the aorta, and subsequently subdivides as shown, giving rise to a long conma typed left subclavian, left and right carotid arteries, and right subclavian artery. This condition thus typifies that found normally in the horse.
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ABBREVIATIONS
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.1., aorta, with its ascending, transverse arch and descending (dorsal) portions
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C, common carotid arteries, (R) right and (L) left
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/., superior intercostal artery
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//., heart
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A'., innominate artery
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M., internal mammary artery 5., subclavian artery, right and left T., transverse scapular artery, including the superficial cervical artery v., vertebral artery, right and left .Y., axillary artery, right and left
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AORTA AND SUBCLAVIAN ARTERIES OF THE RABBIT
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FRAXCIS MARSH BALDWIN
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PLATE 1
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is:}
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Abstracted by Joseph ^1. Thuriiiger, author. Tulane University of Louisiana.
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A suggestion for improvement in projection and drawing
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apparatus.
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By substituting a focusing stage in the drawing apparatus, provided with coarse and fine adjustments, in place of the fixed stage used at present, variations in the magnification of the projected image due to focusing are eliminated, hence more accurate results in reconstruction work may be expected, e\en when slides and cover-glasses in a given series are not of uniform tliickness. The customary arc lam]) is discarded for a new conunercial form of incandescent illuminant which greatlj^ facilitates the control of the light.
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ACTHOR 8 ABSTRACT OF THIS PAPER ISSUED BT THE BIBLIOGRAPHIC SERVICE, JUNE 21
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A SUGGESTION FOR IiAlPROVE.AIENT IN PROJECTION AND DRAWING APPARATUSES
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JOSEPH M. THURINGER Deparlmcnt of Anatomy, Tulane University of Louisiana, New Orleans, Louisiana
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ONE FIGURE
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Among the various tj^pes of apparatus manufactured for the projection of microscopic objects for tracings and drawings, the Edinger drawing and projection apparatus no doubt holds first place, both from a point of usefuhiess and of mechanical stabihty. For the drawing of individual microscopic objects it leaves little to be desired, except perhaps an improved form of illuminant. However, when used for the drawing of serial sections for reconstruction work by any of the various methods in vogue, we are at once confronted with a little more difficult problem.
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It is highly desirable to hold the percentage of error in reconstruction work to a minimum. A well-prepared series of sections, of course, is the essential factor. Secondly, this series should be mounted with slides and cover-glasses of uniform thickness. Even the mounting medium should be of uniform consistency and temperatin-e for a given series, and all the slides after mounting subjected to a drying for a gi\-en number of hours at uniform temperature to insure an absolutely equal distribution of the mounting medimn over the entire surface. With all these precautions carefully observed, there still remains an appreciable somxe of error due to the difference of magnification obtained when using the present focusing devices. The sUghtest change in position of the draw-tube alters the magnification. To increase the efficiency of the above-mentioned apparatus the following changes are suggested and illustrated in the accompanying drawing.
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The stage as manufactm-ed at present is only equipped with a clamp (K) for altering its position. This, however, does not
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185
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186 JOSEPH M. THURINGER
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peiinit siifficiontly ronvoniont and arcuratr adjustment to answer till- purpose of a focusint? sta^c. Tlu' most i)ainstakint; care in the determination of the magnification by means of stage micrometer and rule will lje upset by the slightest change in position of the draw-tube or by having to refocus. To obviate thfs source of error the focusing stage illustrated (S) is suggested It is equipped with a coarse and fine adjustment identical with the one supi)orting the draw-tube of the microscope (.U) and therefore not entailing great additional cost in the mamifacture. This stage could also be supplied to all Edinger apparatuses in present use, thereby bringing them to their highest efficiency. After the desired magnification is once determined, all future adjustments are made by means of the stage coarse and fine adjustments. All errors due to differences in thickness of slides, cover-glasses, and mounting media are thus comjiensated.
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The condenser (.C") is hinged on a support and guide<l by an upright which, however, is not secured to the stage, as at present, thus permitting more room for the use of a mechanical stage.
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The arc lamp, which always reriuired more or less attention and needed new carbons at the most inopportune moment, is here replaced with the new low-voltage, high-amperage, concentrated-filament, incandescent lamp. On direct current this is operated in series with a suitable resistance and on alternating current with a small transformer. Both of these devices can be attached under the drawing table and require no further attention when once adjusted.
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The lamp is heUl by a universal support (f), which allows adjustment vertically as well as horizontally, thus permitting the use of various-sized lami)s.
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\ light-tight, ventilated hood, provided with an adjustable reflector (li), completes the outfit.
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IMPROVEMENT IN PROJECTION APPARATUSES 187
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Fig. 1. Diagram of projection ami drawing apparatus. C", stage condenser; C, condenser; L, lamp in ventilated housing; li, adjustable reflector; U, universal support; S, focusing stage; A', clamp; .1/, microscope.
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Abstracted by James C. Watt, author. University of Toronto.
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Symmetrical liilateral dystopia of the kidneys in a human subject, with outward rotation of the hilus, muhiple arteries and veins, and a persistent posterior cardinal vein.
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In a male human subject, aged twenty-eight, who died of pulmonary tuberculosis, an associated series of rare anomalies of the kidneys was found. There was a symmetrical bilateral displacement caudally, each kidney lying from the level of the second to the fifth lumbar vertebrae. Synnnetrical displacement without fusion is rare. The hilus forms a long, narrow groove, the upper part lying on the anterior surface of the kidney, the remainder describing a spiral cutting around the outer border on to the posterior surface as it proceeds caudad. This lateral position of the hilus is extremely rare, previous ones being found in pelvic kidneys, and very few instances being recorded. On the right side were five renal arteries, two off the aorta, three from the common iliac artery. There were four left renal arteriejs, two from the aorta, one from the connnon iliac, and one from the hyi)ogastric arteries. Two spermatic arteries were present on the right side and three on the left. Two renal veins, uniting into a short common stem tributarj- to the inferior vena cava, occur near the upper pole of each kidney. In addition, on the left is a posterior cardinal vein connected at the ends to the common iliac and upper renal veins and having as tributaries a third renal vein and four lumbar veins. A fourth left renal vein goes to the hypogastric vein. The pelvis of the ureter enters the kidneys anterior to the main vessels. The ureter courses lateral to the kidney.
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author's ABSTR-\.Cr OF THIS PAPER ISSUED BT THE BIBLIOGRAPHIC SERVICE, JUNE 21
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SYMMETRICAL BILATERAL DYSTOPIA OF THE KIDNEYS, IN A HUMAN SUBJECT, WITH OUTWARD ROTATION OF THE HILUS, MULTIPLE ARTERIES AND VEINS, AND A PERSISTENT POSTERIOR CARDINAL VEIN
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JAMES CRAWFORD WATT Department of Anatomy, University of Toronto
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TWO FIGURES
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In the laboratory of the Department of Anatomy of the University of Toronto a very interesting series of associated anomalies relating to the kidneys and their vessels was discovered during the regular course of dissection. The specimen was at once put aside for investigation, and on further study has been considered worthy of a detailed description.
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The body was that of a well-proportioned but somewhat emaciated male, aged twenty-seven, who died of pulmonary tuberculosis. Apart from the abnormalities associated with the kidneys, no other gross anomalies were noticed in this subject.
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THE KIDNEYS
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Shape and size (fig. 2)
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The outline of the kidneys is that of a long, narrow oval. The ventral surface is quite convex, the dorsal surface flattened. Of the two poles, the lower is much thicker than the upper. A shallow groove winding spirally from the \entral surface laterally and caudally on to the dorsal surface forms the hilus, and notches the outer border where it crosses it. Except for the presence of the hilus, the surface is smooth, and shows no special lobulation.
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1S9
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190
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JAMES CRAWFORD WATT
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The measurements taken are as follows:
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Righl kidney I-cft kidney
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Greatest length 10 5 cm. 11cm.
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Width 3. 5-4. 5cm. 3.5-1.5 cm.
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Thickness 2.5-3 5 cm. 2.5-3.0 cm.
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Position and relations (fig. 2)
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The two kidneys exhibit a displacement which is quite symmetrical on both sides. Each lies close in against the psoas
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Iwfenor Ven* C«w4 i^^t*
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Fig. 1 Outline drawing of the kidneys and their vessels and ureters. Veins are solid black, arteries striped, and ureters stippled. Lower part of right kidnev removed.
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major muscle and shows the same degree of obli(iuity as the muscle. The upper i)ole of each kidney is about 1 cm. nearer the midline than the lower pole. The upper pole is opposite the middle of the second hmibar vertel)ra, the lower oposite the lower part of the fifth lumliar. The kidney thus lies with its upper portion in the lumbar region, on the quadratus lumborum muscle, the other portion in the iliac fossa, on the iliacus muscle. The sui)rarenal glands were placed over the upper jiole and slightly to the medial side of each kidney. The left gland was
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RARE ANOMALIES OF THE KIDNEY
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191
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situated in a small space with the kidney below, pancreas above, spleen laterally and vertebrae medially.
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Fig. 2 Drawing of the kidneys to show their relations to the dorsal abdominal wall and the viscera. The duodenum, pancreas, and spleen have been retained in position, the lower part of the duodenum being hooked up to expose the underlying vessels. The suprarenal glands have been removed to expose the upper pole of the kidney. Lower part of right kidney removed.
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The pancreas was situated entirely above the left kidney and crossed right over the spleen. Owing to the downward displacement of the kidney, the spleen was displaced inward and
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192
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JAMES CRAWFORD WATT
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was in contact with the vertebrae medially for two-thirds of its length. The lower pole, however, had the upper pole of the kidney inserted between it and the vertebral column.
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On the right side the kidney and suprarenal gland lay entirely below the level of the liver, which was thus allowed to come into contact with the diaphragm on its posterior surface.
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The upper pole of each kidney and the common renal vein from each side were under cover of the duodenum at the flexure of the latter at the lower end of the descending limb.
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The hilm {fig. 2)
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The po-sition of the hilus is most interesting, and is quite similar on both sides. Starting above, about three centimeters below the upper pole, on the anterior surface, it runs obliquely caudad to cut the lateral border of the kidney, formhig a notch on it about two thirds of the w-ay down. It then curves from here on to the posterior surface, ending about two or three centimeters from the lower end of the kidney.
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The hilus is thus placed on the opposite border to the normal and fonns a spiral with gradually increasing rotation about the polar axis as it proceeds caudad.
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VESSELS Arteries {figs. 1 and 2)
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The renal arteries and also the spennatic arteries of both right left sides are multiple.
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Right side. The right renal arteries are five in number. The first comes off the abdominal aorta at the level of the second lumbar vertebra and goes behind the inferior vena cava to the upper end of the hilus on the anterior surface of the kidney. The second renal artcrj- also goes to this surface, coming from the , aorta at the level of the third lumbar vertebra and running in front of the vena cava.
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Off the right conunoii iliac artery come the third renal artery, a very small one, the fourth, quite large and dividing early into
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R.\EE ANOMALIES OF THE KIDNEY 193
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two, and the fifth, a small artery again. These three arteries running in close company pass behind the lower pole of the kidney and enter the lowermost part of the hilus on the posterior surface.
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The right spermatic arteries are two in number. The higher one arises from the aorta between the first and second renals, and runs posterior to the inferior vena cava and both renal veins, but anterior to the upper pole of the kidney. The lower artery arises from the second renal, goes posterior to the inner renal vein, anterior to the outer vein, and anterior to the kidney. At the lateral border of the kidney the two spermatic arteries and the vein form a common bundle running in contact with this border and the ureter in the iliac fossa, and then turning over the psoas muscle to the internal abdominal ring.
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Left side. There are four left renal arteries. The first is off the aorta at the upper limit of the second lumbar vertebra and runs down anterior to the upper pole of the kidney. The second artery is from the aorta, over the second lumbar vertebra, level with the highest artery on the right. It is also to the hilus on the upper part of the anterior surface of the kidney.
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The third left renal artery is off the left common iliac, and is peculiar in that it runs across the upper part of the iliac fossa behind the kidney, to pass into the hilus just where it cuts across the lateral border.
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The fourth artery is off the internal iliac, or hypogastric artery, just at its conmiencement, and runs anterior to the external iliac artery and psoas major muscle and penetrates the kidney on its medial border just near the lower pole.
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On this side there are three spermatic arteries, the highest coming off a suprarenal branch of the first renal, the other two directly off the first renal. All three arteries and the spermatic vein form a common bundle coursing anteriorh- along the lateral border of the kidnej^ then lateral to the ureter in the iliac fossa and down to the inguinal canal.
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I'.t4
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JAMES CRAWFORD WATT
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Veins (figs. 1 and 2)
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Rigid side. There are two renal veins, both coming from the upper part of the hiliis over the anterior surface of the kidney, and uniting at the level of the upper pole of the organ into a common vein which is about three-quarters of an inch in length and empties directly into the inferior vena cava.
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The right spermatic vein, a single vessel, opened into the lateral (if the two renal veins.
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Lefl side. On this side are three renal veins. Two are quite .similar to those on the right, arising from the anterior surface of the kidney on the upper part of the hilus and uniting into a common stem which crosses anterior to the aorta and empties into the inferior vena cava.
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.Tust at the junction of the above two veins, there comes into the medial one, a longitudinal vein which lies over the front edge of the psoas muscle, on the vertebral colunui, in the interval between the aorta and the left kidney. This steni starts at the level of the fifth lumbar vertebra, and connnunicates with the left conunon iliac vein below. As it ascencis it receives as tributaries four lumbar veins, one of which is double, and also a renal vein. This renal vein comes from the hilus where the latter cuts the outer border of the kidncj', and runs medially posterior to the kidney, alongside of the third renal artery, and ends in this ascending vein. This longitudinal stem is interpreted as a persisting portion of the embryonic posterior cardinal vein of the left side, which lies exactly in the position occupied by this present vein.
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The left spermatic vein, single in spite of the presence of three arteries, empties at the junction point of the two large upper renal veins into the common trunk.
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Ureter {figs. 1 and 2)
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The position and relations of the ureter are remarkably symmetrical on the two sides.
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At its pelvis, each ureter is divided into two parts. One is a long, narrow, tubular jiortioii which lies in the ujiper part of
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RABE ANOMALIES OF THE KIDNEY 195
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the hilus, on the anterior surface of the kidney. The other is a broad, short, funnel-shaped portion communicating with the kidney in the hihis just before the latter cuts round the outer border, of the organ.
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The two parts unite at the lateral border of the kidney, which the ureter now follows to the lower pole, where it then crosses the iliac fossa, turns medially over the psoas muscle and external iliac artery into the pelvis, where its course into the bladder is normal.
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The highest artery and the lateral vein accompany the upper branch of the ureter as it enters the kidney, the vessels lying behind. The other vessels enter the kidney mostly behind the lower branch of the ureter.
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SIMILAR CASES
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Multiple renal arteries and veins in all the locations found in this case have been previously described and discussed by various authors, and so call for no special consideration. Tonkoff ('03), for instance, describes and gives a figure of a right kidney slightly displaced downward and with an arrangment of its four renal arteries almost identical with those of the left kidney in this case.
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Macalister ('8.3) and Morris ('85) both state that abnormal vessels occur in three individuals out of every seven.
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The occurrence of a vena cardinalis posterior along with renal anomalies has been noted before. ]\IeIissinos ('11) found a case of pelvic kidney with a persistent right cardinal vein, and gives reference to a few other instances.
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The presence of the rotation seen in these kidneys, on the contrary, is evidently quite a rare condition. Among the anomalies of position of the hilus, the particular one exhibited here is not even mentioned in the text-books on pathology or surgery. It is self-evident that such a position would be of great interest, especially to the surgeon.
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Gerard ('05), in a review of 527 cases, states that the renal hilus, instead of lying medially, may be superior, inferior, ventral, or dorsal, but does not mention any instance of a lateral position.
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196 JAMES CRAWFORD WATT
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Miillprheiin ('02) describes a case where the left kidney was found in the pelvis, with its hilus not medial, but anterior, and he states that one of the characteristics of dystopia of the kidney is that the hilus is usually anterior in position.
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Morris ('04), in a summarj' of displacements, states that the kidney may be rotated so that the hilus looks upward, outward, directly forward or backward, and mentions one case of the hilus occurring; laterally. This case was described by Farquharson ('94) as a left kidnev placed in the pelvis with hilus looking to the left.
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Brown ('94) also describes a right pelvic kidney which had rotated till its posterior surface had become anterior and the hilus looked posteriorly to the right. Johnson ('14) described a case in the cat exactly similar to that of Brown's and Anitschkow ('12) describes and gives a figure of a left kidney in man displaced slightly back in the Imnbar region and with a hilus which he describes as anterior, but which, in the illustration, appears to course around the lateral border, as there is a marked indentation shown there.
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^IcMurrich ('98), considering a series of crossed dystopia of the kidneys with fusion, pointed out that in nearly all cases the position of the hilus was anterior.
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This retention of an anterior position of tlie hilus in displacements and in fusions of the kidneys is the retention of the normal embrjological position. Pohlman ('05) noted that until the kidney had ascended in the embryo to where it was approximately in the adult j)osition, the hilus was ventral, and then a rotation medially of 90° occurred about the polar axis. FeUx ('12) also states that this rotation occurs, but that a reverse rotation toward the ventral surface also occurs later, so that the hilus is finallj' ventromedial.
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The kidneys in the present case have not reached the usual final level and so might be expected to have retained the hilus anteriorly. This is true of the upper part, but the lower portion exhibits the rare outward rotation through 90° to bring it laterallj', and the lowest part goes even further than this to lie posteriorly. There is thus considerable torsion in the kidney, the hilus forming quite a spiral in its course.
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RARE ANOMALIES OF THE KIDNEY 197
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The fact that the ureter lies ventral to the main renal vessels at the hilus at first sight appears as an anomaly. It will be seen, however, that if the hilus were to be rotated into its usual position the ureter would then lie posterior to the vessels. Thus at their entrance into the kidney these structures stand in their normal relations to each other, but the rotation makes them appear reversed.
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The position of the suprarenal glands is interesting. McJVIurrich, Morris, Miillerheim, and others have all stated that the relation of these glands to the kidneys is merely topographical and that they are found in their usual places in cases where the kidneys are displaced. In this instance, however, they lie closely capping the upper pole of each kidney, and so are displaced somewhat caudally horn their normal location.
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"\Miat was the actual cause of all the anomalies shown above is open to conjecture. It must have been a force acting in early embryonic life. The displacement into the iliac fossa was probably due to lack of growth in the ureter and the torsion due to a twisting of the pelvis of the vu-eter. It is of interest to note that Felix ('12) states that in the lumbar region the ureter shows a dilatation accompanied by a spiral twisting. An exaggeration of this process might possibly account for the result shown here. Whatever the cause may have been, the result is most remarkable for instead of a symmetrical displacement of the whole organ, we have here the upper pole with the upper end of the hilus facing still in the old embryological position, while proceeding caudad there is an ever-increasing torsion evident, until finally at the lower end the hilus shows a displacement of 180° brought about by lateral rotation.
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The position of the kidnej-s in the lower liunbar region and iliac fossa seems to be a much rarer condition than the position within the pehds, as by far the greatest majority of cases of dystopia without fusion are reported as being in the pelvis.
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The symmetrical degree of dystopia shown by these two kidneys seems to be almost as rare a condition as the lateral hilus. In all the cases quoted above and in many others not mentioned here, if the two kidneys are not fused to form the discoidal or the
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THE ANATOMICAL RECOKD, VOL. 19, NO. 3
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1«»8 JAMKS I UAWlOUl) WATT
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liorscshoo kidney, pithor thorois a nnich fiioatordotirco of dystopia on on(> side than on llio other or else only one kiihiey shows displacement, the other beiuf!; in its normal position. Thus the kidneys in this instance are vmicivie in several respects and have therefore seemed well worthy of description.
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BIBLIOCiRAr'HV
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Anitschkow, N. \. 1912 Stiidicn iihcr NicrcnRcfiisse l)(>i Aiigehorener Nicr (•iulysti>]>ic. Virch. Arch, fiir path. .\nat., Bil. 207, S. 21:?. BuowN, M. 1S94 Variations in the positinn and dcvplopmcnt of the kidneys.
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Journ. of Anat. and Physiol., vol. 28. FAHQUinnsox, W. F. 1S94 Case of left kidney, displaced and immovable.
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Journ. of ,\nat. and Physiol., viA. 28. Felix. \V. 1912 The development of the urinoRenital system. Keibel and
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Mall's Human Fmhryology, vol.2, J. B. Lippincott Co., Philadelphia
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and London. GfiR.\KD, n, 19()o I.es anomalies cong(^nitalcs du rein chez I'hommc. Journ.
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(le I'Anaf . et dc la Physiol.. T. 16, p. 241 ct 411. JouN.sox, C. E. 1914 Pelvic and horseshoe kidneys in the domestic cat. .\nat.
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Anzeigcr, Bd. 46, S. 69. M.\CALisTKR, A. 1883 Multiple renal arteries. Journ. of .\nat. and Pliysiol.,
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vol. 17, p. 250. MrMuRHifH, J. P. A case of crossed dystopia of the kidneys with fusion.
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Journ. of .\nat. and Physiol., vol. ,32. Melissinos, von K. 1911 Beckenniere niit persistierender Vena cardinalis
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dextra. ,\nat. Anzeiper, Bd. 30, S. 1 19. Monnis, Hknuy 1S.S,") Surgical diseases of the kidney. Cassell & Co., London.
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19(M Surgical diseases of the kidney and ureter, including injuries,
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malformations and misplacements, vols. 1 and 2. Keener & Co.,
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Chicago, U. S. A. MCXLEKHEiM, U. I'ebcr dei diagnostischc und klinische Bedeutung der con genitalen N'ierendysto))ie, speciell der Beckenniere. Berlin, klin.
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Wochschr., 1902, S. UM. PoHLMAN, .\. (i. 190,1 A note on the developmental relations of the kidney
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and ureter in human embryos. Johns Hopkins IIosp. Bull., vol. 16,
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no. 107, February, 19!t.'). ToKKOfF, \V. 1903 Beitrag zu den Niercnanomalien. Intern. Monatschr. filr
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Anat. und Physiol., Bd. 20, S. 449.
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THE ANATOMICAL RECORD, VOL. 19, NO. 4 SEPTEMBER, 1920
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l{osunion por el aufor, Eben James Caioy. C'ologio Mrdico ("loiphtoii, Omaha.
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Estudios sobre la diiuimica de la histogdnesis. La fuerza que
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motiva ol crc'cimioiito como f^stimulo diiKimico vu la gen(?sis
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de ios tcjidos esqueletico y muscular.
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La iegi6n activa dominante en el crecuniento del intestine es el tuhd opitelial; la zona que crece meno.s activamonte es el mesen(iuima ([ue le rodea. Imi el colon terminal del oerdo el tubo epitelial erece en direcci6n caudo-cefalioa. Las figuras mit6siras siguen en su mayor parte la direceiAn de una helice sinistror.sa. Kn embriones de cerdo de 10 a 25 nun. de longitud, el colon terminal crece relativamente con mas rapidez en diiimetro que en longitud. Dmante este periodo la tunica interna de musculo liso estii en periodo de foniiaci6n. Cuando el embriAn crece de.sde los 25 a los 45 mm. el colon terminal crece mas rapitlamente en longitud que en anchura. Durante este periodo de alargamiento intestinal nipido .se inicia la capa externa de nu'isculo liso. La correlacion del crecimiento tubular epitelial en hmgitud y anchura, con la genesis de las tunicas nnisculares lisas interna y externa, respectivamente. se considera bajo el aspecto de "fuerza que moti\'a el crecimiento." La iegi(^ii de crecimiento acelerado en el miemi)ro en \ ias de de.^arrollo es el m'lcleo estiueletico central; la de crecimiento retardado es el mesenquima que le rodea, el cual se transforma ulteriormente en la musculatura y tejidos conectivos relacionados con ella. Estas dos zonas de crecimiento diferencial se iiiHuyen nuituamente, y esto es evidente objetivamente a causa de un c-ambio ile movimiento y por una alteraci^ii de la forma externa y estrnctuia intei-na de las celulas afectadas. El j)rimer material 6seo tlel embri6n .-ie distribuye econ6micamente en la periferia al principio, sobre la superficie convexa mas di'bil del femur curvo. Despues el hueso envuelve al centro de la diafisis y aparece en el lado c6ncavo del femur cartilagiiioso cmvo. La correhici6n entre el crecimiento esciueletico acelerado y el de.sarroUo mesenquinuitico retardado se con.sidera con referenda a la "fuerza que motiva el crecimiento diferencial."
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TraruilBtion by Jof*^ V. Nunidcf Cornell Mrdirnl College, New York
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AUTHORS ABSTRACT OF THIS PAPER ISSUED BY THE BIBLIOGRAPHIC SERVICE, JUhl 26
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STUDIES IN THE DYNA:\nCS OF HISTOGENESIS
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GROWTH MOTIVE FORCE AS A DYNAMIC STIMULLTS TO THE GENESIS OF MUSCULAR AND SKELETAL TISSUES
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EBEN J. CAREY
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Department of A nalomy, Marquette University Medical School, Milwaukee, Wisconsin
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TWENTY FIGURES
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CONTENTS
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Introduction 199
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Definition of growth motive force 200
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Early stages in the histogenesis and morphogenesis of the descending colon
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of the pig (Sus scrofa) 205
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Spiral path of mitosis in epithelium of colon 206
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Growth motive force in intestinal development 210
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Definition and classification of strains 211
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Growth motive force in limb development 215
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Summar}' 219
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Literature cited 224
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INTRODUCTION
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The principle of unequal growth constantly confronts the emhryologist in his investigations. The local thickenings and foldings of the central nervous system, the unequal growth of the cardiac septa, the elongated intestinal tract, are common instances exemplifying the principle that the body parts develop at different rates.
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This idea was recognized by Ai-istotle, but was not definitely formulated until 1774 from Wolff's convincing studies. In the latter's work on intestinal development the principle of unequal growth was definitely established and elaborated considerablj-. In 1874, His compared the various layers of the chick embryo to plates and tubes of an elastic nature. From these he suggested that some of the principal organs are molded bj^ local zones of unequal growth. Davenport ('96) resolves the changes in ques 199
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200 EBEN J. CAUEY
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tinn into iiiovonipnts of cells or coll aRRiogatos, the latter beiiiK linear, superficial, or massive. He still further classifies each of these three divisions.
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These local zones of uneciual growth anil the movements of cells have l)cen looked upon by Horl)st ('94) and Dreisch ('94) as physiological responses to definite stiTuuli. His and Davenport as well as Roux ('95) aim at something more than a mere description of unequal growth and ontogenetic events. They made an attempt to give a mechanical causal explanation for these processes. The function and aetiology were considered side by side with structure.
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It is from the dynamic view-point that the present investigation was pursued. It is desired to emphasize the fact that in zones of imequal or differential growth, in limb and intestinal development, that an interaction of forces takes place, resulting in a transference of energy, and that these forces are factors in histogenesis. This action and reaction and transference of energ>' is due to a definite entity, growth motive force, a temi introduced by the writer.
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Growth molive force is any agency which tends to produce a transfer of kinetic energy, from an active to a less active group of cells, and of potential energy from a less active to an active group, in a cellular field of differential growth until equilibrium is established. The active and less active zones are in reference to the rate of cell di\-ision per millimeter of cross-section. This principle was deduced from a series of studies on osteogenesis and myogenesis begun in 1914. Previous reports of a part of this work have been presented to the Association of .\merican Anatomists (Carey, '17, '18, '19).
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The understanding of the causes underlying tissue formation or differentiation of an unspecialized cell is the central difliculty for the student of development .
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The increase of cellular components, the transfonnation of these, and the perfection oi fonn out of the relatively fonnless antecedents are phenomena which demand the closest analysis. Growth and division of the nucleus, however, are merely changes concomitant with the specialization which the cell undergoes.
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GROWTH MOTIVE FORCE 201
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There are three theories regardmg cellular differentiation: first, the 'mosaic theory' of Roux ('88), later modified by Wilson ('04), Conklin ('05), Zeleny ('04), and Boveri ('04); second, the 'organization theory' of ^ATiitman ('93) and more recently elaborated by Child ('15) in the latter's studies on metabolic gradients and individuaUty ; third, the 'homogeneity theory' of Dreisch ('91-'93). Dreisch considers the peculiar organizing quality of protoplasm as due to the expression of a mysterious force wholly different from anj- in the inorganic world.
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At least in certain of the earliest stages, the primordial cell is modified during development by the environment. It is not independent in its development but is dependent upon an interaction of developing parts before its external form and internal structure are perfected. This is the theory expressed by the terms, mutual interaction, correlation, interdependent s, dependent differentiation or differentiation due to position. This theory is upheld by His ('74), Hertwig ('94), Fischel ('98), Von Baer (1828), Pfluger ('83), C. Schultze (1900), Hans Dreisch ('94), Zoja ('95), Whitman ('94), Child ('99) and Thoma ('07) and to a limited extent by Roux. The latter investigator distinguished two periods in the development of the body parts: first, a period of self-differentiation iir which the parts arise, grow, and differentiate of themselves; second, a period of functional form development in which the more complete formation of the parts is accomplished through the influence of stimuli.
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As to the first view, it has been convincingly proved that there are organ-forming stuffs in the cytoplasm. Wilson ('04) concluded from his studies that the cytoplasm of the primordial germ cell contains certain specific organ-forming stuffs which have a definite arrangement. These observations of Wilson have been confirmed by Conklin ('05), Zeleny ('04), Boveri ('04).
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The third theorj' regards differentiation as dependent upon either an extrinsic or an intrinsic factor. Differentiation so considered is in the nature of a physiological response to a stimulus. The structure of the reacting as well as of the stimulating body, however, contributes to the quality of the effect. Specialization by this method is simply an 'induction,' according to Dreisch.
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202 EBEN J. CARET
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It is an effect jiroduceil upon the parts that are developing bj' other (lovelopinK parts or by an extrinsic factor in the environment. Three elements are conseeiuentlj- involved: first, the stimulus; second, the reception of the stimulus; third, the response. The first is some other organ or external agent ; the second and third are functions of the organ in process of formation. Lack of evidence has been the chief obstacles to the acceptance of Dreish's theory of induction.
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The term induction' implies an effect or change pioduced without contact. But, in respect to the primordium of the muscular and skeletal ti-ssues, there is a definite .sj'ncj'tial continuitj-. Consequently, any effect produced by either tissue upon the other would l)c through 'conduction' and not through 'induction.'
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In this action, through conduction of the ileveloping skeletal and muscular tis.sues upon each other, the factor of force is inherently involved. The primordial blastemal skeleton is undergoing the most rapid growth, as a consequence of which a tensional elongating or .stretching action is bound to be exerted upon the surrounding and less actively growing, continuous, syncytial mesenchyme. It is desired, therefore, to emphasize the following facts:
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First, that there is a force manifested by rajiid skeletal growth.
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Second, that this force exerts a ten.sional or .stretching action upon the surrounding mesenchyme, influencing the first steps of myogenesis.
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Third, that the first differentiated muscles react upon the primordial blastcnud skeleton resulting in a definite series of changes. These are seen in the formation of the conden.sed cartilaginous skeleton and later, as the muscles become more developed and vigorous in physiological function, in the formation of the osseous skeleton.
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This action and reaction of forming parts results in the condition that at .Tny period of development the degree of differentiation of the musculature and skeleton represents an e(|uilibrium estabii.shed l)etween oppo.sing myogenic and skeletal forces. .Mechanically, therefore, skeletal and the related muscular tis
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GROWTH MOTIVE FORCE 203
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sues are interdependent, one relying upon the other for its initial and continued differentiation.
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The foregoing appUes to the skeleton and skeletal cross-striated musculature. Concerning the smooth muscle of the intestine there is a similar interaction of differential forming parts. The epithelial lining of the alimentary tube is the most active region of growth. The growth in diameter in the early stages is due almost entirely to the rapid degree of mitosis of the epitheliimi and not to the surrounding mesenchyma forming the bulk of the wall. As a consequence the lumen rapidly increases in diameter, and it is this increase which causes primarily the diametrical growth of the intestine. It is readily apparent that the rapid distention of the lumen due to epithelial growth would cause a tension upon the relatively passive, contiguous, syncytial mesenchyme. This action would tend to draw out or stretch the mesenchymal cells in a concentric manner somewhat similar to the tension put upon the strained elastic fibers of a rubber balloon when distended with air, the pressure of epithelial growth being comparable to the air pressure.
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Once the encircling mesenchymal cells have formed a definite ring, the expanding lumen would meet a resistance to growth in diameter. The growth force, pursuing the lines of least resistance, would be directed in a longitudinal manner due to the shifting of the planes of mitosis from a longitudinal to a transverse direction. This shift is directly due to the external resistance of the first-formed ring of inner circular smooth muscle.
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At this point the term force is one that will stand close scrutiny and careful thought on the pai-t of the embryologist. A force is one of a pair of equal, opposite, and simultaneous actions between two bodies by which the state of their motions is altered or a change in form in the bodies themselves is effected. Pressure, attraction, repulsion, and traction are instances in point. Muscular sensation conveys an idea of force, while a spring balance gives an absolute measure of it, and a beam balance only a relative measure. In accordance with Newton's third law of motion that action and reaction are equal, opposite, and simultaneous, forces always occur in pairs.
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21(4 EBEN J. CAREY
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Foicp is exerted in eertuin reffion.s of the embryo I)}- the genesis of ;i rapidly dividing Kioup of eells upon a less active or relatively passive group of eells. In turn the relatively passive group react ujxm the former. This action and reaction is ohjectiveh' evident by a retardation or alteration of the rate of growth or by u change produced in the external form or internal structure of the cells involved.
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The most rapidly divitling grou)) of cells in a difTerential growing cellular field in syncytial continuity is subjected to a force tending to direct it in the path in which the resistance diminishes most rapidly, that is in the direction of a line of force. The mo.st rapitlly growing cells raise the kinetic energy of the field at the point of rapid growth above that of surrounding points, and hence a transference of encrg>' takes place until e(iiiilibrium is established. There will be a transfer of kinetic encrgj- from the growing to the passive group of cells resulting in an elongation of the latter and a consequent storage of potential energy due to position. On the other hand, there will be a transference of potential energy from the elongated relatively passive group of cells to the mo\'ing or growing group which will tend to restrict or retard the motion or growth of the fonner. This motive force of genesis, growth, and tlifferentiation continues until the difference in energj- disappears.
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These biological generalizations are analogous to electromotive force. If two metal spheres at different jwtontials be connected by a wire, a transfer of positive electrification will take place from the one of higher to the one of the lower potential, or a transfer of negative electrification from the one of lower to the one of higher potential, or of both, until the difference of potential disappears. The higher and lower electrical potentials are analogous to the continuous zones of rajiidly dividing and less active group of cells, resjiectively. The term electromotive force is applied to any agency which tends to produce a transfer of electrification as exemplifictl above. Growth motive force consequently may be defined as any agency which tends to produce a transfer of kinetic and potential energy in a cellular field of ditTercntial growth.
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GROWTH MOTIVE FORCE 205
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EARLY STAGES IN THE HISTOGENESIS AND MORPHOGENESIS OF THE DESCENDING COLON OF THE PIG (SUS SCROFA)
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The increase or decrease in size of certain parts of the intestine and the celkilar transformations which occur are of fiuidamental importance. By analysis and careful description of the changes which occur in sequence and by subseciuent synthesis of the data obtained, an interesting correlation in dynamics is thereby detected. Heretofore investigators of histogenesis have had independent and isolated view-points in their work on intestinal development, no correlation of the developmental processes being attempted. The admirable descriptive observations on intestinal development by McGill ('07) and Johnson ('11) fulfill the purpose of their respective authors, but lacked interpretation and correlation of the facts observed. Their point of view was descriptive morphology, not dynamic.
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In an embiyo 10 mm. in length the descending colon presents in cross-section an oblong ovaL or pear-shaped appearance, the convexitj^ of which is directed toward the interior of the abdominal coelomic cavity. The tapermg end is attached to the dorsal abdominal wall through the intermediation of the relatively long and thick dorsal mesentery. There are three main elements which demand close attention (fig. 1). The first of these is the inner epithelial tube; the second, the outer peritoneal epithelium, and the third, the intermediate mesenchymal zone.
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The inner epithelial tube in cross-section is oval in shape contaming a narrow oblong lumen with rounded ends. The lining cells of this tube form from two to three rows of nuclei. jNIitosis is usually found in the superficial row of cells. At this stage mitotic activity is prominent in the epithelial cells. The basal row of cells rest upon a well-marked basement membrane.
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This basement membrane is directly contiguous to the intermediate mesenchymal zone. In this zone no clear-cut cell is found. The entire region is composed of protoplasm in syncytial continuitj^ embedded in which are found the nuclei. The nuclei are oval or roimd and present averj' dense network of chromatin, especially well seen when stained with iron-hematoxylin. The membranes of the nuclei are decidedly distinct. The protoplasm
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206 EBEN J. CAREY
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is pramilar, prosontinp: an inomilar network structure. Scattered in tlie niesenchyinal rejijion are seen isolated discrete vesicles. These are especially con^iegated toward the dorsal mesenteric attachment. The vascular vesicles are variable in size and shape and inesent vari(jus ile^n^es of confluence.
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The thickness of the mesenchymal wall is nearly twice that of the diameter of the epithelial tube. It is to the rapid increase in diameter of the latter, due to rapid epithelial mitosis, that the uicreasc in width of the intestine is to be ascribetl. The mesenchyme remains relatively passive, and as a consequence is put under great tension by the internal distention of the epithelial tube.
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Attention is especially directed to this difference in the rate of growth between the inner epithelial lining and the intermediate zone of mesench>nnal cells. The continued differentiation of the intestine is pivoted upon this fact. Furthermore, the epithelial distention is not a uniform one., Mitosis takes place in a spiral manner from the anal toward the ileocecal \alve. Conseciuently, the rapid growth of the epithelial tube is a specific type from below ujiwards.
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The attention of the writer was directed to the fact, after l)lotting hundreds of intestinal epithelial mitotic figures, that these figures were usually confined to some definite region of the circumference of a single section. This region was found to change at diflferent levels of the serial sections. By graphic reconstruction (sections 45 to 04) this plot was found to form the path of a definite spiral describing a dexiotropic rotation in one case; in nineteen others the path was a left-handed sjMral. The si)iral itself presented a head or apical n^gion in which mitotic figures were found to be numerous and a tail or ba.sal end in which there were fewer and fewer figures. The apical end of the spiral path is always directetl toward the iliocecal valve and the basal end toward the rectum. (Jrowth is therefore from below upward in a sjjiral course. One sjjiral growth is (juickly followed by a second which rifles a i)ath slightly lateral to its predecessor. This in turn is followed by a third, in a path still more lateral, and so on around the circumference. This intermittent rhythm
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GROWTH MOTIVE FORCE 207
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of explosive spiral growth may be compared to that of the successive fire balls emitted by a roman candle in fireworks. The paths formed by this explosi\-e spiral growth may be compared to those within the barrel of a Winchester rifle.
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Lining the outer peripheral portion of the mesenchynae is the peritoneal epithelium. In the 10-mm. embryo this is a single layer of oval or cuboidal cells. These are continuous from the dorsal mesentery and envelop the primiti^'e colon proper. The cell walls of this layer are contiguous and give a beaded appearance to the peritoneal epithelium. Later in development this cellular layer becomes flattened and markedly elongated, the individual cells becoming more and more attenuated and spindle-shaped.
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The beginning of this flattening or elongation of the peritoneal epithelium is seen in a 14-mm. embryo (fig. 2). This cross-section represents the corresponding region of the descending colon in the 10-mm. embryo described above (fig. 1). In addition to the elongation of the nuclei, the cytoplasm is drawn out into a fine membrane between the separated nuclei. At the same time that the peritoneal epithelium is elongated, the epithelial tube is seen to have grown double in size, whereas the mesenchyme has only increased one-half that of the former stage observed.
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The lumen of the epithelial tube is directed more transverse than vertical to the long axis of the gut . The lining cells appear to be overcrowding at the lower pole of the lumen due to rapid mitosis. This condition gives a stratified appearance to the epithelimn. This rapid mitosis constantly causes an increase of free surface, and consequently the lumen rapidly dilates in width.
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Concomitant with the rapid increase in width of the epithelial tube, there is observed a change in shape and rearrangement of the surrounding mesench>^^^al cells. The nuclei and surroundmg granular protoplasm become elongated in a definite direction. Instead of the irregular arrangement characterizing the oval nuclei and stellate cytoplasm lieforc. there is now observed a definite tendency for the cells to form concentric layers. This tendency is more marked in the midzone of the mesenchjane between the epithelial basement memlirane and the outer shnple epithelial peritoneum. In this miilregion there is a condensation
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20S EBEN J. C.VKEV
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more dofinitp at the upjior (fig. 2) than at the lower pole of the epithelial tube and greater in cither polar region than on the lateral aspects of the tube.
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With a further absolute increase in diameter of the epithelial tube (fig. 3) over that of the intestinal wall, the smooth muscle elements become more elongated, flattened, and spindle-shaped, and the definitive inner circular smooth muscle layer becomes more clearly defined out of its fonner nebulous state (fig. 2). By actual measurement with the filar micrometer, the intestinal wall is seen to become thiimer as the epithelial tube constantly increases in size. The embrj'o is now approxunately 20 mm. in length, and during this jieriod it is convincingly seen that the long axis of the elongated nuclei are arranged along the paths of concentric circles. The longitudinal gianular fibrils are likewise arrangetl in this concentric manner.
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^^'ith the constant increase in width of the epithelial tube there is a progressively greater and greater elongation of the muscle elements — nuclei and granular fibrils. These fibrils branch and anastomose with neighboring fibrils, and constantly maintain the original continuity of the protoplasmic sjTicj-tium. With the ever-increasing tension of the fibrils there is a progressive loss of water and increase in viscosity.' Definite physicochemical changes take jilace in the granular fibrils resulting in condensation and fusion of the granules into a continuous coarse irregular strand. Near the nuclei the swellings upon the strand are marked, but toward the poles of the nuclei the fibrils are more attenuated.
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As fonnerly reporte<l by McCill, there is the same tendency in the development of the colonic, nuiscles to form coarse and fine myofibrils as detected in the oesophagus. These fibrils are of variable length and run through several neighboring cells in many cases. The coarse and fine granular fibrils are seen side by side. The coarser ones being primarily located at the periphery' of the ill-defined spindle cell, whereas the finer graimlar myofibrils are located more internally and nearer to the nucleus. Between the fibrils more or less undifi"erentiated granular cytoplasm persists.
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' The chemical elianges in myogenesis will be reported later with my colleague in biochemistn', Victor K. Levine.
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GROWTH MOTIVE FORCE 209
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In embryos, between 24 and 4() mm., the descending colon increases rapidly in length. Peripherad to the inner smoothmuscle coat there is found the beginning of elongation of cells similar to that described for the inner smooth-muscle coat. Similar changes in shape and arrangement of the components take place, however, in a longitudinal rather than in a transverse plane. At first this layer is more or less uniform throughout (figs. 3 and 4), but there is soon detected a greater proUferation of cells immediately underlying the dorsal mesentery. This aggregation of cells represents the inception of the longitudinal mesenteric taenia coli band of fibrils. This is definitely seen in figure 6.
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The initial genesis of the mesenteric taenia coli before the other bands appear is significant. If we remember that this location represents the outer curvature of a coiled tube in the process of rapid formation, it is readily seen that more definite tension of differential growth is exerted at this location. These bands are more definitely developed nearer the ileocecal valve. The dynamics involved will be considered later.
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The longitudinal muscle, however, is only slightly developed at 28 mm., and at 45 mm. is not as conspicuous as the myenteric Auerbach's plexus. This plexus is located between the welldeveloped circular smooth-muscle coat and the attenuated outer longitudinal-muscle coat. The nerve plexus at these stages 10 to 46 mm. is composed of a continuous layer of groups of cells with crowded nuclei and many non-medullated fibers.
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The inner submucous plexus of Meissner is not as prominent as the outer one. It is similarly constructed, although it contains fewer and much smaller ganglia and the meshes of the plexus are much finer. The tenninal nerve fibers were traced to the epithelium and between the epithelial cells at 46-mm. stage. The plexus first appears along the inner border of the inner circular coat.
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The muscularis mucosa is not differentiated at 45 nmi. The lymphatic channels, however, are abundant at 32 mm. along the line of the mesenteric attachment. L>^nphatic nodules are not formed, on the other hand, in the submucosa until the 150-mm. stage is reached.
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210 EBEN J. CAREY
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The lumen of the doscoiuliuK colon is patent thiougliout developnient; no sign of atresia is observed. Between the 10- and l4-niin. stages small vacuoles were found, but no diverticulae are seen. At 10 and 14 mm. the colon is round or slightly elliptical in shape, gradually enlarging toward the cloaca. The lumen possess in tlie earliest stages a shape comparable to that of the entire tube. Between 53- and 46-mm. stages, however, lateral, evaginations are do\eloj)ed which give the lumen a crucial instead of a round or elliptical appearance. These evaginations push out at the lateral aspects where the circular muscle is least developed, along Unes of least resistance. At the dorsal and ventral poles of the lumen the smooth muscle forms a thicker layer than on the lateral aspects. In addition, resistance is still further increased by the formation of the longitudinal mesenteric taenia along the dorsal, attached margin of the descending colon.
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GROWTH MOTIVE FORCE TX INTESTINAL DEVELOPMENT
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In the inorganic world that which jiroduces motion or pressure is considered as due to a force. This entity has already been defined. One result of its action on an elastic body, namely, a strain, should now be considered. This is imperative, for if mechanical forces are at work on organic matter the\' tend to ])roduoe similar results as those acting upon inert matter. Too frequently the term self-difTerentiation is applied to alteration of form and internal structure of developing cells without searching the inunediate environment of the specializing cells or syncytium to ascertain whether or not these changes are attributable to forces outside of the differentiating zone. This applies particularly to the differentiation of bone and muscle tissue. If a cell changes in form successively through the spherical, ellip.soid, and spindle stages it undergoes a strain. A strain is usually due to an external force wliich elicits internal reacting stres.ses in the body acted upon, ("ytological differentiation is frequently a manifestation of these internal reacting stresses.
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It will prove to be an illuminating study to search for the celhilar forces outside of the inimediate differentiating zone under
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GROWTH MOTIVE FORCE 211
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observation. This search necessitates lower magnifications in order to enlarge our field of view. Heretofore cytological differentiation has been studied per se with magnifications of 1000 to 2000 diameters which considerably reduces our range of view. The higher magnifications are profitable in revealing cytological detail,, but the interpretation of the process is lost unless in conjunction with the higher, intermediate magnifications are used. By employing all possible magnifications of the microscope in connection with naked-eye studies we are less likelj^ to lose the forest for the trees. Such a method is likely to reveal the interaction of related developing jiarts. Before applying this method it will be of advantage to consider biiefly the different types of strain with wliich we are concerned.
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DEFINITION AND CLAS.SIFICATIOX OF STRAINS
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Elastic bodies are those in which a change takes place in the relative positions of their parts in contradistinction to rigid bodies in which no change occurs in the relative positions of their parts. Elastic bodies may suffer changes in their size or shape. Any definite alteration in the form or dimensions of an elastic body is called a strain.
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This fact may be brought out in the following illustration: A rod which becomes longer or .shorter is strained. Water when compressed is strained. A stone, beam, or mass of metal in a building or in a piece of framework, if condensed or dilated in any direction or bent, twisted or distorted in any way is said to experience a strain. A ship is said to 'strain' if, in launching or when working in a heavy sea, its different parts experience relative motions.
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The simplest strain is a Unear one. The stretching of an elastic cord is an example. This strain is called homogeneous when every portion of the cord has its length changed in the same ratio, so that the ratio of the initial to the final length of each part is the same as this ratio for the whole. The ratio of the final to the initial length is called the ratio of the strain; it represents evidently the quantity by which the initial length must be multiplied to obtain the final length. The elongation is the
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212 EBEX J. CAREY
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ratio of the change in the length to the initial length. A negative elongation, or shortening, is called a compression. A j)ositive elongation, or lengthening, is called a tension.
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When all linos in a bodj* parallel to a certain direction are changed in the same ratio, and no lines peqjendicular to these arc changed either in length or direction, the bodj' suffers a strain of simple elongation. If. however, a second set of lines at right angles to these also suffer such a change, then there is elongation in two perpendicular directions: and if these lines are all in the same ])lane, the strain is a surface strain. A square elastic sheet, if the longation be e in a direction parallel to one edge, and e' parallel to another, will be converted by the strain into a rectangular sheet, the sides of which are proportional to the strainratios. Evidentlj- two equal and parallel lines drawn on the square will remain equal and parallel after the change in form; and the strain will be homogeneous. If the elastic sheet be circular, the strain will change the circle into an ellipse, the two perpendicular directions which remain perpendicular after the strain becf)ming the axis of the ellipse. If these lines remain parallel to their original directions, the elongations take place along them and the strain is called a pure strain. If not, the strain is compounded of a pure strain and a rotation.
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As seen above, the jjrincipal axis of a strain is the principal axis of the ellipse into which the strain converts a circle. If the increase of length along one such principal axis is equal to the decrea.se of length along the other principal axis, the strain under these circumstances is called a .shear. Evidently in a shear the area of the plane itself remains unaltered. Any plane figure may be converted into a strained figure; that is, the shearing strain may be jiroduced simply by fixing one of its sides, and moving all lines parallel to this fixed side in their own directions, through spaces which are proportional distai>ces from this fixed line. The amount of this sUding motion which takes place between lines which are unit distance apart is called the amount of shear.
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When a solid body undergoes a strain, a change may take place in its dimensions in one or more of three perpendicular directions. If the strain is such that all parallel lines within it are altered in
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GROWTH MOTIVE FORCE 213
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length ill the same ratio, the strain is called a uniform or homogeneous strain, as previously pointed out. Thus, for example, a sphere when subjected to strain is converted into an ellipsoid, a sohd every plane action of which is an eUipse. This ellipsoid is called a strain-ellipsoid. In any homogeneous strain of a solid body there are three directions at right angles to one another, which remain perpendicular after the strain. These directions are those of the three principal axes of the strainellipsoid.
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Along one of these directions the elongation is greater and along another less than along any other direction in the body. Along the remaining one the elongation is intermediate. The principal axis of a strain is the principal axis of the ellipsoid into which it converts a sphere. The principal elongations of a strain are the elongations in the direction of its principal axis. According to Thomson and Tait, Any strain may be viewed as compounded of a uniform dilatation in all directions, superimposed on a simple elongation in the direction of one principal axes, superimposed on a simple shear in the plane of the other two principal axes." With this brief account of the nature of strain we may now pass on to the consideration of the effects of differential growth in intestinal development.
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The most rapidly growing part of the intestine is the epithelial tube (figs. 1 to 6). In 10- to 23-mm. embryos the descending colon grows relatively more rapid in diameter than in length. The increase in diameter is due primarilj^ to the rapid growth of the entodermal epithelial tube and only partiall}' to its surrounding mesenchymal cloak. The latter is relatively passive in growth with respect to the former. It is during this early increase in diameter that the inner smooth-muscle coat is in the process of formation. The mesenchymal cells are drawn out gradually in a definite series of concentric rings. These rings appear not unlike those of the planet Saturn and the annular nebula in Lyra.
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A definite centripetal force is active in the rapid, spiral growth of the intestinal epithelial tube. The surrounding mesenchymal cells arc thrown into a definite series of concentric rings accord THE ANATOMICAL RECORD, VOL. 19. NO. 4
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214 EBEN J. CAREY
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ing to their various densities. Those possessing the greatest density joining the outer ring in the tangential path of the force, '.vhoreas the inner rings will he composed of bodies forming a gradient of decreasing dcMisities. The cells forming the outer ring will he most elongated. Their water content decreases and viscositj^ increases.
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As this concentric initial sniooth-nuiscle laj-cr becomes differentiated it tends to restrict the diametrical growth of the epithelial tube. The epithelial mitotic figures under this restriction shift their i^lanes of division from a right angle to a parallel position with the smooth-muscle colls. This shifting results in an elongation of the intestine.
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In embryos 25 to 40 mm. in length, the elongation of the descending colon is more rapid in growth than that of the diameter. It is iluring this period that the outer longitudinal muscular coat is in the process of formation. The rapid growth of the epithelial tulie in length tends to elongate the peripheral undifferentiated mesenchymal cells which were not directly involved in the formation of the inner smooth muscular coat.
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The differentiation of the outer longitudinal muscle coat therefore coincides, in time, with the rajiid growth in length of the intestinal ejiitheliimi. The inner smooth-muscle coat, on the other hand, is formed during the period of the rapid growth of the intestinal epithelial tube in diameter.
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In this study, the initial zone of rapid growth is found in the epithelial cells. Kinetic energy is transferred from within to the surrounding splanchnic mesenchjnie by rapid spiral expansion of the entodernial epithelial tube. The less actively growing cells of the perii)heral region of the intestinal wall are elongated. Later the potential energy of the elongated cells is tran.sferred to those of theepitholium, resulting in a retardation of the growth in diameter. Inuncdiately following this retardation of diametrical growth, the period of rapid growth of the intestine in length takes place. In this development, therefore, the factor of growth motive force, as a cause in the transference of kinetic and j)otential energy, is definitely detected.
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'
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GROWTH MOTIVE FORCE 215
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Once the formation of the inner circular muscular rings is fairly established, a resistance to growth in width is encountered by the cells surrounding the rapidly dilating lumen. These cells then grow primaril}^ along the path of least resistance in a longitudinal manner. At this stage the lontitudinal muscle cell, spherical in shape in figure 15, is elongated to a spindle-shape structure in figm'e 16.
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In conclusion an interesting correlation in the development of the oesophagus in the human may be cited. This correlation was detected in the work of Jackson ('09) and in that of Keibel and Elze ('08). The former investigator studied the developmental topography of the oesophagus, the two latter the histogenesis of the oesophagus. Jackson states that the descent of the stomach is accompanied by a great elongation of the oesophagus. In a 9.4-mm. specimen the oesophagus measm-es 1.8 mm. ; at this proportion, it should measure 4.3 mm. in an embryo 22.8 mm., but its actual length is found to be 8 mm. The year previously Keibel and Elze reported that the oesophagus in 12.5-mm. embryos show a circular but no longitudinal muscle layer; in 17-mm. embryos they find a circular layer with the longitudinal layer faintly indicated. The histogenesis of the outer longitudinal layer of the oesophagus as studied bj' Keibel and Elze coincides in time with the rapid elongation of the oesophagus, due to the descent of the stomach, as recorded by Jackson.
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GROWTH MOTIVE FORCE IN LIMB DEVELOPMENT
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The detailed description of the direct observations made on bone and skeletal muscular development will be reserved for a subsequent communication.
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When the embryo is approximately 10 mm. in length, the first indication of the limb is a bud filled with a densely packed mass of uniform mesenchymal cells. Eventually, when the embryo is 14 min. in length, a condensation of nuclei is detected in the center of the bud. This central condensation represents the primordial blastemal skeleton. It is the most rapidly moving or growing part of the hmb. This is evident by the greater number
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216 EBEN J. CAUEY
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of mitotic figures and bj* the relative scarcity of cytoplasm and conso(niont closely compact nuclei. As the central core of the linil) pushes forth more ra])icll}' tiian that of the ])eripheral continuous mesenchymal cells, there is a tendency for the latter to be pulled out, stretched, or elongated l)y the former. The traction force of the rapidly growing a})jiendicular core exerted ujion the surrounding mcsenchj-me is the internal stimulus of a correlated part, resulting in the elongation of the nuclei of the prenniscular mass in the direction of the blastemal skeletal growth.
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From this direct observation that the cells of the premuscular mass are elongated in the direction of skeletal growth, we detect the objective evidence of the transference of kinetic energy from the zone of rapid growth to that of the relatively passive one. As differential growth continues and the growth motive force becomes more and more manifest, there is also detected a drawing out or stretching of the perii)heral syncytial cyto])Iasm in the direction of the skeletal growth. This is first shown l)y the appearance of relatively parallel rows of discrete, isolated granules which represent differences in density of the cytoplasm due to the traction to which it is subjected. This is comparable to the tendency of a viscid substance, like egg albumen, to collect in droplets if placed between two glass slides when these are separated In- a shearing force.
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When the viscosity of the cytojilasm increases, on the other hand, with increased structural differentiation, these granules fuse and form a continuous condensed cytoplasmic strand known as the myofiliril. At first this myofibril is coarse, l)ut as the traction of skv'letal growtli continues it gives rise to numerous fil)rils finer in texture. Thus, there is a direct proportional increase of the cytoplasmic comjionents with continued skeletal growth. The formation of the embryonic skeletal nuisdes represents a definite reaction to the growth of the skeleton. These muscles tend to restrict the growth of the skeleton in length. This is manifesteil by an increasing condensation of the skeletal core.
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This condensation is seen in the transition of the densely nucleated syncytial blastemal skeleton into the cartilaginous skeleton. The greater stability of the latter counteracts the deforma
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GROWTH MOTIVE FORCE 217
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tion that would naturally occur in the former as the primitive muscles begin to contract. On the other hand, with increased skeletal condensation there is presented a more rigid base, and this in turn acts as a stimulus to more definite muscular differentiation. This is detected by direct observation in the splitting up of the uniform premuscular masses into its individual muscular components. Muscular foi'ces become consequently more definitely applied and the definitive parts of the skeleton become more clearly outlined.
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As the growth motive force of differential growth continues, the musculature becomes too vigorous for the cartilaginous base. The blastemal skeleton, as noted above, is supplanted by the cartilaginous one; there is now found another replacement of the cartilaginous by the osseous skeleton.
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The changes which occur in a cartilaginous component of the skeleton, as the femur, in the formation of the more stable bonj" base, together with the concomitant muscular changes are as follows :
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1. There is a bending of the cartilaginous femur with the con^•exity of the bow directed toward the M. quadriceps extensor. This deformation is incident to the contractilitj' of the thigh musculature and the inception of the adduction action in rotatiozi of the hind limb. This femoral strain is due to active and passive muscular stresses.
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2. A strain fibrosis is detected on the weaker convex tensile aspect of the cur\ed femur resulting in the histogenesis of the primary perichondrium which subsequently encircles the shaft.
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3. Concomitant with increased muscular differentiation and subsequent activity there is a progressive dehydration, increase of viscosity, and increase of total acidity (table 1).
 +
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4. Inception of necrobiosis of the cartilage cells is seen immediately underlying the initial location of formation of the primary encapsulating perichondrium. This necrotic change is ilue to the diminished blood supply caused by the restricting action of the forming perichondrium. By injection and serial sectioning methods it is revealed that all capillaries and incipient discrete \esicles, precursors of capillaries, are peripherad to the primary perichondrium.
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 +
 +
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218
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 +
 +
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EBEN J. CAREY
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 +
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5. The vesiculated cartilage cells are arranged along definite curved tensile and conipressile stress lines. Previous to the bending of the femur these cells are irregularly related to one another.
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6. Hyalinization of cartilaginous matrix in the central zone of the cur\eil femur is next observed.
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 +
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T.\BLE 1
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 +
 +
LENOTH or EMBRTO
 +
 +
 +
TITBATION or 1 ORAM Of EUBRTONIC PREUFSCLB AND UCSCCLAR TISSUE TO .'"^ NaOH
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 +
 +
mm.
 +
 +
 +
«■
 +
 +
 +
10
 +
 +
 +
2 5
 +
 +
 +
12
 +
 +
 +
3.5
 +
 +
 +
13
 +
 +
 +
3.5
 +
 +
 +
u
 +
 +
 +
4.9
 +
 +
 +
16
 +
 +
 +
9.0
 +
 +
 +
19
 +
 +
 +
11.0
 +
 +
 +
20
 +
 +
 +
13.0
 +
 +
 +
22
 +
 +
 +
14.0
 +
 +
 +
23
 +
 +
 +
13 5
 +
 +
 +
24
 +
 +
 +
13.8
 +
 +
 +
25
 +
 +
 +
17.0
 +
 +
 +
27
 +
 +
 +
23.0
 +
 +
 +
30
 +
 +
 +
21.5
 +
 +
 +
32
 +
 +
 +
24
 +
 +
 +
35
 +
 +
 +
27.8
 +
 +
 +
37
 +
 +
 +
31
 +
 +
 +
39
 +
 +
 +
32.1
 +
 +
 +
40
 +
 +
 +
31.5
 +
 +
 +
42
 +
 +
 +
34.0
 +
 +
 +
45
 +
 +
 +
35.5
 +
 +
 +
 +
7. Calcification then takes place in the hyalinized matrix. These intergrading steps in the condensation of the matrix is incident to increased muscular growth and functional activity and to the passive resistance of the musculature to skeletal elongation.
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8. .\ subperiosteal osteogenetic and constricting cellular zone is begun immediately underlying the initial zone of fibrosis on the summit of the convexitj- of the curved femoral rod. This osteoblastic constriction fjuickly encircles the shaft. This is the
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GROWTH MOTIVE FORCE 219
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beginning of a consecutive series of bony deposition. This bony deposit is due to two factors: first, the stimulus of the functionally active thigh muscles and, second, the stimulus of the restriction to growth at the ends of the rapidly elongating femoral rod due to passive muscular resistance. These two factors tend to stimulate the formation of the osseous skeleton in replacing the calcified cartilaginous skeleton.
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From the foregoing brief account it is desired to emphasize the following :
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That there is a direct transference of kinetic energy from the more rapidly growing skeleton to the less actively growing primitive musculature and a reactive transference of potential energy from the latter to the former, tending to a condition of equilibration. With the inception of functional muscular activity there is a direct transference of kinetic energy from this tissue to the growing skeleton tending to retard or alter its motion or growth. The resistance passively manifested by the muscles is an additional factor tending to inhibit skeletal growth. This fact is also noted by Holl, Schomberg, and especially by Bardeen. In this case there is a transfer of potential energy due to position from the muscles to the skeleton. This acti^'e and passive play of the muscles on the cartilaginous base resulting in a condensation of a more stable framework and the consequent more definite effect of the latter on the former is due to a direct transference of energy by conduction. This transference of energy is of fundamental importance and is produced by the motive force of differential growth.
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SUMMARY Intestinal development
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1. The region of most active mitosis, per mm. of cross-section, in the intestine is the entodermal epithelial tube. The mitotic figures primarilj' follow a path of a left-handed helLx.
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2. The region of least active or relati\-ely passive growth per mm. cross-section is the mesenchyme, derived from the splanchnic mesoderm, surrounding the epithelial tube.
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■_"_'() EBEN J. CAREY
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3. The rapid oxpansioii duo to epithelial growth in a rotating spiral inaniipr of" the iiitostiiial lumoii is firoator than the activity uianifpst in the suiroundiiiK* mesenchyme. This causes a pressure in the latter lesultinR in a flattening and an elongation of the mesenchymal cells. The successive changes in .shajie of these cells through the spherical, ellipsoidal, and spindle cellular pha.ses are seen. The mesenchymal wall decreases in thickness, due to tension caused l)v epithelial tul)ular dilation.
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4. The rotating spiral growth of the epithelial cell.'f causes the formation of a series of mesenchymal cellular and fibrilla