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THE
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ANATOMICAL RECOED
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EDITORIAL BOARD Irvixg Hakdestt Wakren H. Levhs
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Tulane University Johns Hopkins UnlverBlty
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Clarence M. Jackson Charles F. W. McClure
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University of Minnesota Princeton University
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Thomas G. Lee Wiluam 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 Hcber, Managing Editor
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1330 Hill Street, Ann Arbor, Michigan
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VOLUME 16
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MARCH-AUGUST,
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PHILADELPHIA THE WISTAR INSTITUTE OF ANATOMY AND BIOLOGV
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CONTENTS
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1919
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NO. 1. MARCH
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C. W. M. PoYXTER. Some observations on wound healing in the early embryo. Twelve
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figures ^
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ExRA. Allen-. A technique which preserves the normal cytological conditions in both
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germinal and interstitial tissue in the testis of the albino rat (Mus norvegicus albinus).
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Eleven figures 2o
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Harrison- R. Hunt. The variations of the inferior thyroid vein of the domestic cat.
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Seven figures 39
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NO. 2. APRIL
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Eben J. Carey. Teratological studies. A. On a phocomelus, with especial reference to the extremities. B. The external form of an abnormal himaan embryo of 23 days.
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C. The anomalies of an anencephalic monster. Complete craniorrhachischisis
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D. A second anencephalic monster. Complete craniorrhachischisis. Seventeen figures 45
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Maby Drusilla Flather. The blood supply of the areas of Langerhans, a comparative study from pancreas of vertebrates. (Preliminary paper.) Eight figures 71
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Inez Whipple Wilder. An anomaly in the portal circulation of the cat. Four figures. 79
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Harbison R. Hunt. Vascular abnormalities in a domestic cat (Felis domestica). One figure 87
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Ezra Allen. Degeneration in the albino rat test is due to a diet deficient in the watersoluble vitamine, with a comparison of similar degeneration in rats differently treated and a consideration of the Sertoli tissue. Seventeen figures 93
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NO. 3. MAY
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Robert Retzer. Ralph Edward Sheldon. In Memoriam 119
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Proceedings of The American Association of Anatomists. Thirty-fifth session 129
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Proceedings of The American Association of Anatomists. Abstracts 137
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Proceedings of The American Association of Anatomists. Demonstrations 170
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American Association of Anatomists. Officers and list of members 175
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Frank Blair Hanson. On teaching the germ layers. Five figures 193
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Frank Bl,\ir Hanson. The coracoid of Sus scrofa. Six figures 197
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H.E.Jordan. Studies on striped muscle structure. IV. Intercalated discs in voluntary
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striped muscle. One figure 203
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NO. 4. JUNE
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H. E. Jordan. 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. Three plates (thirty figures) 217
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H. D. GooDALE. Interstitial cells in the gonads of domestic fowl. Four figures 247
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RcTH Rand Atterbury. Bursa and tonsilla pharyngea; a note on the relations in the
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embryo calf. Eight figures 251
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C. V. Morrill. Sjonmetry reversal and mirror imaging in monstrous trout, and a comparison with similar conditions in human double monsters. Three plates (eight figures) 265
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NO. 5. JULY
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Edward Phelps Allis, Jr. The innervation of the intermandibularis and geniohyoideus muscles of the bony fishes. One figure 293
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Fra.ncis Marsh Baldwin. Variations in the carotid arteries of the rabbit. One plate (twelve figures) 309
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James Frederick Rogers. The leverage of the foot. One figure 317
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Robert W. Henderson. The adult lymphatic system of the striped ground-squirrel (Spermophylus tridecemlineatus Mitchell). Six figures 319
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NO. 6. AUGUST
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Otto F. Kampmeier. A summary of a monograph on the morphology of the lymphatic system in the anuran amphibia, with especial reference to its origin and development 341
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George W. Tannreutuer. Partial and complete duplicity in chick embryos. Six
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figures 355
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Leo C. Ma.ssopust. A simple method of preparing daylight glass 369
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Harrison R. Hunt. Birth of two unequally developed cat fetuses (Felis domestica).. Two figures 371
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Edga:< F. Cyriax. A brief note on "floating" clavicle 379
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Resuniido por el autor, C. W. M. Poynter.
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Algunas observaciones sobre la cicatrizacion de las heridas en el
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embri6n j6ven.
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El proceso de la cicatrizaci6n de las heridas ha sido estudiado por el autor en embriones de gallina muy j6venes, observados en gota pendiente, y tambien en cortes. Las heridas producidas en el blastodermo extra-embrionario se cicatrizan a consecuencia de la actividad de las tres hojas blast odeniiicas. En el embrion este proceso estd limitado casi exclusivamente al ectodermo. En la cicatrizacion pueden reconocerse cuatro estados: 1, ajustamiento de las celulas; 2, desdiferenciacion ; 3, emigraci6n celular; 4, rediferenciacion. La desdiferenciaci6n tiene lugar muy temprano en el proceso, tomando las celulas el mismo caracter, de tal modo que presentan el mismo aspecto y reacciones bajo la acci6n de los colorantes. Las celulas desdiferenciadas se \aielven a diferenciar de nuevo en celulas con el mismo tipo que las caracterfsticas de la hoja blastodermica que las origino. La emigraci6n de las celulas es de un caracter amiboide y la- prolif eraoi6n celular no toma parte en el proceso de la cicatrizacion.
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Translated by Dr. Jos^ Xonider Columbia University
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author's abstract of this - PAPER ISSUED BT THE BIBLIOGRAPHIC SERVICE, FEBRUARY 24
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SO:^IE OBSERVATIONS OX WOUND HEALING IN THE
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EARLY EMBRY0
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C. W. M. POYXTER Anatomical Department, University of Xebraska Medical College, Omaha, Nebraska
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TWELVE FIGURES
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"VMiile engaged in the study of degeneration of ceUs in the early chick embn'O. it became necessan^ to observe the reaction of cells under the stimulus of an injur\'. The present paper is concerned with the reaction of tissues to injur}- and the suggested process involved in wound healing. The use of young embrj'onal material, on account of its elemental structure, permits us to study the healing process under somewhat simplified conditions and by direct observ-ation.
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Chick embn,"os ranging from ten to twenty-nine somites were selected for the experunents. Eggs were incubated for from eighteen to forty-eight hours, then opened under aseptic precautions and the embry^os injured with a fine knife or hot needle: some were then placed on the hanging drop for immediate observation while others were sealed and returned to the incubator for various periods up to one hundred and twenty hours. The operations consisted in incisions of various parts of the blastoderm, removal of sections of tissue and cauterization of the embryo at different points.
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For periods of short duration up to four hours the hangingdrop method was employed and direct observations made; all of this material was also sectioned for additional stud}-. This method has been so frequently' described that it is not necessary^ to re\dew it in detail. It was originated, I beheve, by Harrison and has been developed by a large group of workers, notable among whom are ^NlcWhorter and Whipple ('12), who fii-st applied it to the study of the entire embryo.
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2 C. W. M. POYNTER
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For this study I have used the technique suggested by Margaret R. Lewis ('11), growing the embryo in Locke's solution without dextrose. An electrically heated stage incubator was employed in which it was possible to keep the chick ahve for seven hours. I found it most satisfactorj'^ to transfer the embryo from the egg to warm Locke's solution for removing the vitelline membrane and washing away the excess yolk before placing on the hanging drop. In some cases the embryo was operated on while in the solution, but it was generally more satisfactory to first place it on the cover-slip; this facilitated handling, permitted operation under high-power observation w^hen desired and allowed adjustment in the moist chamber with the least disturbance of the embryo. It is desirable to use aseptic precautions throughout the manipulations and very necessary to keep the embryo very near incubator temperature. For the observation of the grow^th process I used a monobjective binocular, for it permits the use of high magnifications, produces a certain amount of stereoscopic effect and, what is more important to me, permits several hours' continuous observation without producing excessive fatigue of the eyes. When any observed process reached a desired point the chick on the cover slip was fixed in osmic acid and so carried into paraffin. When in 70 per cent alcohol, slight care to see that the fluid circulates freely between the embryo and the glass wdll insure the easy removal of the embryo from the cover-glass in the embedding process. The usual methods of sectioning and staining were employed and merit no comment.
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OBSERVATIONS ON THE LIVE CHICK
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Some of the changes which may be observed in the live embryo appear so simple as to be hardly worthy of record, and it is only when one remembers the large amount of material and the hours of patient work necessary to gain the same information from slides that the value of this method is reahzed. It must alsobe remembered that this method gives added value to the stained sections, for a process can be watched till it reaches the desired stage or one difficult of interpretation and then fixed.
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WOUND HEALING IN THE EARLY EMBRYO 6
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After injury changes take place very rapidly, so it is desirable to place the hanging-drop preparation under the microscope as soon as possible. If a wound is examined a minute or two after it has been made the edges appear ragged and broken. The border is made up of fragments of cells and free cells. Within five minutes the borders of the wound have become smooth in outline due to the readjustment of cells. The broken cells are carried away and the free cells move about till all irregularities are overcome. The cells from one germ layer do not become incorporated in the other germ laj^ers, but these readjustments take place independentl}^ in each layer. In observing the beha\dor of the cells during this period one is reminded of the repulsion and attraction which electric poles have for a pith ball. There is a. noticeable current in the fluid of the drop directed away from the wound; this is probably an out-pouring of the fluids of the tissues and is undoubtedly one of the factors involved in the movement of the debris away from the wound margin. In the case of certain detached cells there is an attraction sufficiently strong to overcome the movement of fluid away from the wound and cause them to move back again in contact with the undisturbed cells and become incorporated in the growing margin. This behavior of the unattached cells suggests the experiments of Driesch ('96) who, by shaking, displaced the primary mesenchymal cells of Echirus. In the course of a few hours these scattered cells rearranged themselves so that development proceeded in a normal wa}. Both are examples of what Roux ('96) called 'cytotaxis' and which he suggested was due to local differences in the superficial tension of the cells. I have not seen injured cells, i.e., cells which have had part of their cytoplasm cut away, incorporated in the growing wound margin, but think farther observations should be made on this point.
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Observations on the extra embryonal blastoderm show that all three germ layers take part in the healing process. The ectoderm and the entoderm are somewhat more active than the mesoderm. Within thirty minutes after the operation the borders of the wound are noticeably thicker than the region farther back and the rent is narrower than in the beginning
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4 C. W. M. POYNTER
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(fig. 1). The piling up of the cells at the edge of the wound is a constant feature of all wounds observed in the extra-embryonal blastoderm. It would seem to be an expression of the difference between the gradient resulting from wound stimulus and the force of surface tension of the germ-layer mass.
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At this time all of the cells of the wound margin are round and more transparent than those of the undisturbed blastoderm. They may be said to have taken on an indifferent character for the indi\idual cells in their morphologj^ furnish no indication of the germ layer from which they have been derived. I must make an exception to this in the case of the cells of the entoderm of the area opaca which may still be identified by the yolk granules present in the cells. The cells of the different germ layers are alike only in appearance. Dedifferentiation has occurred to the extent that the characteristics of the parent germ layer are lost and to this extent the cells are in an indifferent state. They are, however, only relatively indifferent for, at least as long as normal stimuli operate, each cell will remain in the germ-layer group of common origin and later differentiates, or redifferentiates, into the germ-layer type from which it sprung. At no time during the healing process are the cells distributed evenly over the wound, but those derived from each layer remain together to build up, or advance, that layer. I have never observed any cell from one layer become incorporated with those of another layer, even when the relations seemed most favorable for such an adjustment. For example, when examining a border in which the ectoderm was slightly behind the other layers none of the cells pushed in to fill the gap. This is illustrated in figure 2.
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The process of healing, or building up of the wound margin, is difficult to interpret, notwithstanding that the process takes place immediately under the eyes and can be readily observed. At first, as cited above, there is an adjustment of cells on the edge of the wound so that the surface becomes regular and in the case of syncytium an adjustment of cytoplasm about the border nuclei with the formation of recognizable cell membranes (fig. 1). The cells near the border seem to become loosened
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TS'OrXD HEALIXG IX THE EARLY EMBRYO O
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from each other and approach spherical shape. The cj^toplasm increases, becomes less granular and the nuclei and nuclear membrane almost indistinguishable. There is a for^'ard movement of the entire tissue mass and frequently at some distance from the wound border individual cells may be seen moving toward the border more rapidly, edging their vi-ay among the other cells till they reach the margin where they take on the characters of the border cells. The healing process is quite rapid; a fissure 2 mm. wide had entirely closed in two hours and twenty minutes, leading only a slightly more transparent area to indicate the line of juncture. As soon as the two wound borders come in contact the cells of the thickened borders begin a readjustment which soon leaves the cell layers of the same uniform thickness they were before the wound was produced. The cells of the borders graduall}' resume the tj^Dical appearance of those in the undisturbed laj^ers and within four hours no visible evidence of a wound remains. The activity of the border distal to the embrj'o seems to be as great as that next to the embryo. An observation of the wound margin for some time suggests that growth acti\'ity is not constant for the whole. This produces a shghtly v^-avY appearance; for example, an area was noticed which advanced for a tune more rapidh' than that on either side of it ; then a period of decreased acti\ity ensued of such duration that the area became the most retarded in the region and appeared as a depression; later growth acti^-ity was resumed. I can only suggest that possibl}" the products of cell metabohsm, which on account of the great acti\'ity are not ehminated, act as an inhibitor to cell movement.
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Injuries of the embri'o present a slightly different picture. If the wound borders are close together, in contact, there is a shifting of the cells of the wound margin and the appearance of the clear cells already described which come in contact with those of the opposite side and so produce union per primam intentionem. All of the germ layers seem to take part in this process and union is brought about through cell dedifferentiation and adjustment.
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b C. W. M. POYNTER
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"When tissue is cut away, as in the removal of a lateral portion of the embryo, there is a readjustment of cells similar to that described for the extra-embryonal blastoderm, then the process becomes very much slower. During a four-hour period of observation the ectodermal and entodermal borders could be seen to advance slowly over the exposed mesenchyme b}^ the process noted above, with the exception that the ectoderm was much more active then the entoderm and the cells of the border did not tend to pile up. The only response of the mesenchyme to wound stimulus seemed to be a shifting of cytoplasm so that a continuous cytoplasmic border could be seen. This border was like a cell membrane, but, except in the case of the mesothelium, was never observed to produce a distinct layer of surface cells.
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The behavior of the spinal cord was observed in various regions, but may be best studied in transverse sections. As in the other tissues, immediate proximity of the cut surfaces seems to stimulate cell activity, and primary union is observed to take place in two to three hours. In the case of an exposed surface reaction is very slow. Adjustment of cells closes the end of the canal and covers the surface with closely arranged cells. This surface layer is derived by the shifting of cells. It seems that certain cells which are exposed by the cut do not take part in this general movement, but are finally covered by other cells which come to occupy their place in the superficial layer. Careful observation has failed to discover any distinguishable difference between cells which are active in forming the surface layer and those which are covered by it.
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From the most careful observations I was able to make I did not discover an instance of indirect cell division. The healing process seems to be accomplished through a general movement of cells and cell layers and changes in the cells which, with modification, may be called dediff erentiation ; only at a later period can we consider normal cell multiplication as a factor in wound repair.
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WOUND HEALING IX THE EARLY EMBRYO 7
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STUDY OF SECTIONS
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Figure 1 is taken from experiment 170. The age of this embn'o at the tinie of operation was about forty hours. The operation consisted in making a long cut in the outer border of the area pellucida, about opposite the heart and to the right of the embrs'o. The wound margins separated widely, due to the pressure of the yolk. After incubating for two hours the blastoderm was fixed for examination.
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The edges of the wound show the pihng up of dedifferentiated cells at the border of each germ layer as already described in the preceding section. These cells are large clear cells with distinct ceU membrane, the}' take the stain Hghtl}' and those of one cell layer are indistinguishable from those of the other layers. All examples of the early periods of the heahng process show that the activity of the three germ laj^ers of the extra-embrs'onic blastoderm is nearly the same. There are no evidences in any of these sections of indirect or direct ceU di\dsion.
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Figure 3 is taken from experiment 172, in which the wound was a tear made with a fine needle with the object of removing only the ectoderm laj'er. The experiment was fairly satisfactory', for the major portion of the wound consisted of an area of from i to 2 mm. broad denuded of ectoderm: at one end of the wound the needle entirely pierced the membranes, which was an advantage, for it permitted the study of different degrees of injurs^ for comparison. The figure shows an area in which there has been a union of the two torn margins of ectodenn. .\11 of the wound margin is made up of dedifferentiated cells, and when, as in the figure, the borders have fused there is as yet no evidence of redifferentiation. In this experiment the healing process was allowed to proceed for seven hours.
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A study of these sections shows that the wound stimulus is not transmitted from an injured to an uninjured cell layer. When, as in the figure, the ectoderm is destroyed there is a reaction of the border cells of this layer but none of the mesoderm although it is exposed. Wound stimulus is apparently directly related to the injury or separation of cells in any cell
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8 C. W. M. POYNTER
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layer, the different layers behaving for the time being as separate individuals. It seems that the ectoderm is uninfluenced in the speed of its reaction by the presence of the other layers. A wound, for example, 1 mm. broad involving the ectoderm alone closes in the same time as one involving all three layers, other conditions being the same.
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p]xperiment 173 was an operation similar to those described above, on an embryo forty-eight hours old with five hours as the duration of the healing process. This wound was almost 2 mm. broad with rough edges and included all three germ layers. When examined at fixation, the wound was found to be entirely closed. The wound area was very easily made out, for the juncture of the two margins was marked by a thickening due to the large number of indifferent cells present. The division between the ectoderm and mesoderm is not distinguishable nor is it possible to discover any line of juncture of the wound borders. All of these dedifferentiated cells appear so much alike that there are no physical characters to suggest from which germ layer any of them have sprung. At this stage, while there is no indication of a wound border it has been found that the wound can be easily reopened. Repeatedly in experiments showing perfect union at fixation, the most careful handling has not prevented a ruinous tear before the material could be safely embedded.
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Experiment 201 is illustrated in figure 5. A blastoderm about twenty-four hours old had a large hole torn in the extra-pmbryonic blastoderm. The egg was resealed and allowed to incubate for twenty-four hours. When the blastoderm was removed from the 3^olk a large hole still remained, but the edges of the opening appeared smooth and healed. The stained sections show that the wound margins are filled with indifferent cells and that through these the germ layers are fused. Except in primary union, 1 have not found the germ layers of the border united in this way earlier than eighteen hours after the injtiry was inflicted.
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Figure 6 is taken from experiment 11 in which the conditions were the same as in experiment 201 except that the healing proc
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WOUND HEALING IN THE EARLY EMBRYO 9
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ess was allowed to proceed for twenty-eight hours. In this experiment the gejrm layers are still separated and the picture very much resembles figure 1, only there are more redifferentiated cells at the border of each layer. It seems that the three germ layers remain separate at the wound margin, as in figure 6, till such time as the freedom from embryonal dominance produced by wound stimulus is overcome, then the indifferent cells fuse into one mass and redifferentiation begins. The mass of dedifferentiated cells seldom exceeds in size that seen in the figure. In wound margins of this type, which are twenty-four hours old or older, the outer cell layer of the indifferent mass frequently shows degenerative changes or even distintegration. These changes are probably due to lack of nutrition.
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Experiment 28, shown in figure 7, was an operation similar to that of experiment 201, in a blastoderm of twenty-hours' incubation. The healing process was allowed to proceed for fiftyfour hours. In this, as in all experiments when the healing process has been allowed to continue for forty-eight hours or more, the fusion of the border layers is complete and redifferentiation has occurred. The ectoderm joins the entoderm so that the line of juncture is hardly discernible and the mesoderm fuses with mesoderm to form a single continuous plate.
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Wounds of the amnion were observed to behave in the same way as those I have just outlined, so it is unnecessary to repeat the observations made on this membrane. Barfurth, '02, and Lillie, '03, have both observed the closure of wounds of the amnion.
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Experiment 212 was made on an embryo about thirty-four hours old. A cut was made parallel to the long axis of the embryo and a short distance lateral to the spinal cord, completely dividing all of the tissues. The wound edges were separated widely, the egg resealed and allowed to incubate for five hours. The sections show the difference in reaction between the embryo and the extra-embryonic blastoderm. The denuded mesenchyme shows a definite border where the readjustment already described had occurred, but there has been no active dedifferentiation of cells. The advancing border of ectoderm
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10 C. W. M. POYNTER
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shows dedifferentiated cells at its edge, but there is no tendency for these to pile up in the way observed above. The entoderm shows much less reaction to the wound stimulus than the ectoderm. At later stages when the ectoderm has almost covered the exposed mesenchyme of the somatopleure there is a shifting of cells of the mesenchyme, so that the coelom becomes closed through the fusion of the two mesodermal plates. The process seems to be brought about, at least in part, by shifting and fusion of dedifferentiated mesothelial cells. Figure 8 is taken from this experiment.
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Figure 9 is taken from experiment 54 in which conditions were the same as in experiment 212 except that healing was allowed to proceed for twenty-four hours. This shows the tw'o plates fused, covered by ectodermal epithelium and the healing process complete except for the redifferentiation of mesodermal cells where the two mesenchymal plates joined.
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If a large area has been denuded of its epitheUum it wall take more than twenty-four hours for it to become covered. In all wounds of the embryo the greater activity of the ectoderm as compared with the entoderm is very noticeable. The tendency of dedifferentiated cells to pile up along the advancing border of either ectoderm or entoderm is very much less than in the extra-embryonic blastoderm. After about twenty-four hours mitotic figures can occasionally be seen in the cells of the wound margin, but never in sufficient numbers to warrant the conclusion that cell division is more active here than in regions more remote, nor that cell division, even at this time, plays a major role in the healing process.
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A study of wounds of the spinal cord shows that there is no apparent change after the first readjustment of cells observed in the section above. After a longer or a shorter time the ectodermal epithelium covers the exposed cord tissue in the same manner as that just described for the mesenchyme. Figure 10 is taken from an obUque section cutting through a transected cord in which the healing process had proceeded for twenty-four hours. The section shows the advancing border of the epithelium and the reaction of the cord cells on the wound margin.
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WOUND HEALING IN THE EARLY EMBRYO 11
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Figure 11 taken from another experiment on the cord is shown to illustrate the closure of the neural canal. I have alreadyspoken of the early closure of the canal by a shifting of cells. This is followed by a collapse of the canal for a distance of from 0.3 to 1 mm. from the transection. The two lateral walls of the cord come into contact as if through lateral compression and the canal is entirely obliterated. There is, however, no true fusion of the cells of the two lateral halves of the cord and a distinct line of separation can always be made out.
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All of the examples I have used in this study have been from incised or torn wounds. The experiments in which the hot needle was used were not entirely satisfactorj\ It was necessary to work very rapidly with the needle or it would become too cool to cauterize properly. This made it impossible to do careful operations or exactly limit the amount of damage to the tissues. If the needle was too hot it tended to stick to the tissues and in freeing it much unintentional damage was inflicted. In the experiments studied there was the same type of reaction to wound stimulus as when a simple incision was made, but the process was much more difficult to interpret because of the injured cells and necrotic tissue present. Figure 12, taken from experiment 62, shows the effect of forty-eight hours' heaUng of a wound of the somatopleure produced with a hot needle.
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The experiments cover observations on embryos as young as the ten-somite stage and as old as the twenty-nine-somite stage. No differences in the degree or type of reaction have been noted for the different ages. Observations were made up to 120 hours after the injuries were inflicted. This is a longer time than is necessary for processes covered in this paper, for redifferentiation is complete in most cases by the end of sixty hours. The later observ^ations suggest that the chick may survive very serious mutilation and go on developing in a normal way but that it is incapable of regeneration in the sense that the term has been used for the simpler animals. Simple wound heaUng seems to be the only reaction to wound stimulus of which warmblooded animals are capable and in this respect the embryo, at least the chick embryo, reacts as does the adult.
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12 C. M'. M. POYNTER
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DISCUSSION
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The reaction, common to all animals, by which wound surfaces become closed through a process called healing has long been recognized. Within the last two hundred years observations and experiments on the possibilities of regeneration have broadened our knowledge of this important reaction and suggested problems of the greatest biological interest. The earlier studies concerned themselves with the behavior of organs and tissues of adult vertebrates. More recently the ability of different animals to regenerate lost parts or to regenerate an entire individual from a fragment has received the major attention of biologists. The general questions concerning the extent of regeneration, its histogenesis and the conditions effecting it furnish a field for research of the most fundamental importance.
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'\^'ound healing seems to be one step or phase of the general process of regeneration. In the lower animals the closure of the wound is followed by continued local growth leading to a more or less complete restoration of lost parts. The higher we go in the animal scale the greater the complexity of organization and the less the power of a part to reproduce the whole. Among the higher vertebrates almost all that remains of the process of regeneration is the reaction of wound repair. Wound heahng, particularly in man, has been very extensively studied. There are, however, many unsolved problems still confronting us. A comparative study of the regenerative process in embryos and adults of the higher vertebrates has received very little attention. The reaction of the embryo to wound stimulus offers an opportunity to study the process under somewhat simplified conditions and not only adds to our knowledge of the problem of regeneration, but throws light on the general growth question as well.
 +
 +
Fraisse ('85) studied the regeneration of epidermis on the tail of amphibian larvae and gave an historical account of epithelial regeneration for vertebrates. He concluded that, in adults, the epithelium regenerated from epithelium by cell proliferation. Tliis was contrary to the generally accepted theory that epi
 +
 +
 +
WOUND HEALING IN THE EARLY EMBRYO 13
 +
 +
thelium might arise as the result of a metamorphosis of leucocytes and contran' to his own observations on larvae, or rather in spite of the fact that he saw no evidence of cell di\'ision nor new cell formation.
 +
 +
Barfurth ('9-i) studied regeneration of the germ layers of amphibian larvae. He noted that the time of closure of the wound was directh' dependent on its size and that the ectoderm reacted more rapidly than the entoderm, due, he believed, to its greater elasticity and the firmer manner in which the cells are held together. He made a sharp distinction in the healing time between a cut and a tear, finding that a clean cut healed more rapidly. In the chick there is very Uttle difference in the reaction time of the different germ laj^ers of the extra-embrv^onic blastoderm, and except in the time of adjustment, which is ■neghgible, it seems to make no difference whether a wound is incised or torn. Barfurth noticed the piling up of cells, "consisting solely of cells torn from the IsLjer," which he called, after Roux, Extraovata. He said, The extraovata after reaching a certain size comes under dominance of the embrj^o. If it passes beyond the dominance of the embryo it will develop into a separate embryo." It is probable that the extraovata is of the same character as the mass of indifferent cells I have noted on the border of the wound in the chick. In the chick, however, the mass does not reach a size nor behave in a way to suggest an extraovata. The higher organization of the chick and the consequently greater dominance of the embryo probably accounts for the difference between the two forms.
 +
 +
Born ( 96) also studied amphibian larvae and concerned himself with the way in which the cicatrix was covered by the epithelium. He observed (p. 579): "On account of the time in which the epithelial covering is completed, mitotic division of cells is not to be thought of. It appears to me, that the epithelium as a whole is concentrically shifted (vergeshoben) over the wound surface, — for the picture does not suggest an active wandering out of the individual cells." As already pointed out, I am in entire agreement with the conclusions that there is a general shifting of the epithelial layer and absence of cell divi
 +
 +
 +
14 C. W. M. POYNTER
 +
 +
sion. but in the chick tlie border of the wound suggests the locus of greatest cell reactiim and I see no evidence for the conclusion (p. 572) that the movement of the whole layer is due to the vital effort of the individual cells to flatten themselves over the greatest possible surface. It is impossible to observe the loosening up of cells near the border and the behavior of the cells at the extreme margin without being impressed with the fact that the advance is an active, not a passive one. I must conclude, as Rand ('05) has for the earthworm, that "We are compelled to look in the indi\'idual cell itself for the immediate source of activit3\"
 +
 +
Oppel ('13) and Osowski ('14) studied the beha\^or of the epithelium on explants of frog larvae and concluded that the movements of the epithelium are responsible for the covering of the wound, not through some pressure behind, but as a direct result of the activity of the cells themselves. Osowski speaks of the action as due to 'Massenbewegung.' He observed no pseudopodia, consequently does not look on the movement as amoeboid in character.
 +
 +
Holmes ('14) repeated the work of Osowski but reached a different conclusion concerning the way in which the cells moved. He decided that "The extension of epidermis in both larval and adult forms is due to the amoeboid activity of the hyaline protoplasm along the margin of the extending mass." I was unable to observe pseudopodia on any of the advancing cells, but this is valueless as negative evidence, for Holmes pointed out that, "The pseudopodia of epithelial cells of amphibian larvae are so short and so fine that it would scarcely be possible to detect them when they are extended over other parts." Tomorphologists who find satisfaction in tangible structure, the discovery of pseudopodia will offer additional proof of individual cell activity.
 +
 +
Harrison ('14) has shown that cells growing in vitero possess stereotropism and suggests that this may explain in a measure cell movement on wounds. The phenomena of stereotropism and cytotaxis, already alluded to, suggest that the movement of epithelial cells is in response to a direct stimulus of chemico
 +
 +
 +
WOUND HEALING IN THE EARLY EMBRYO 15
 +
 +
physical nature. We ha\'e already s^een that the beha\dor of the ectoderm of the extra-embryonic blastoderm is different from that on the embryo. If the behavior were the same we would not have a gap in the blastoderm bridged, but the ectoderm would immediately advance over the mesoderm to unite with the entoderm and a healed border would result; a reaction which does not take place till several hours have elapsed, and then only in extensive wounds. JNIay it not be that in tissues remote from the embryo the wound stimulus, for a time, frees the cells of the border from the natural gradients and makes them behave as independent individiials ; later as the stimulus is exhausted the normal gradients are reestablished and the ectoderm behaves as it does on the embryo?
 +
 +
LilUe ('03) studied the powers of regeneration of various organs in the chick. He was interested primarily in correlative dififerentiation, but recognized the existence of wound repair in these embryos. Shorey ('09) also studied regeneration in the chick. Both observers concluded that, beyond wound repair, no regeneration is to be expected for the chick.
 +
 +
I have referred to the changes which take place in cells of the wound margin by which they lose their distinguishing germlayer characters. These cells may be said to have dedifferentiated or become indifferent, but they always take on again later, when normal 'conditions are reestabhshed, the type form they had before the wound stimulus was operative. So much has been written of dedifferentiation in recent years that it is not necessar}' to review the literature. In lower animals, as those in which a whole part or individual may regenerate from a fragment of tissue, the commonly held theory seems to be that the new part or individual is developed by the dedifferentiation of the old tissue cells and their redifferentiation into tissues of the new individual.
 +
 +
Minot (08) presented a different view, he said "If the head or tail of a planarian is cut off the part lost is regenerated, not bj^ growth of the old tissue, but perhaps wholly by multiplication and differentiation of 'formative' cells w^hich migrate to the place where the}' are needed and produce the structure required."
 +
 +
THE ANATOMICAL RECORD, VOI-. 16. NO. I
 +
 +
 +
 +
16 C. Vi\ M. I'OYNTKR
 +
 +
Agaiii he called these cells "of enibryoiuil type, that is to say, cells of the young type." It would seem that there is much experimental evidence lacking to establish the theory of 'formative' cells, and while there are many connective-tissue cells which are difficult to classify, their behavior is not sufficiently understood to warrant the conclusion that they are 'young cells' capable of differentiation in any direction.
 +
 +
If we accept the theory that cells under certain conditions are capable of dedifferentiation and redifTerentiation it may be qualified, for an examination of the experimental work in this field indicates that the potentialities of dedifTerentiated cells are influenced by certain known factors. The cut end of a planarian may be made to grow either a head or a tail at the will of the experimenter; but as we advance to animals of more complex organization the extent of regeneration becomes less and less. Child ('15) has pointed out, "That the inhibition or retardation of new individuation by the dominant region of an individual occurs when the original gradient is sufficiently fixed in protoplasm." That would mean that the further we advance in the animal scale the greater the dominance of the 'original gradient,' hence the more limited the process of regeneration. If the original gradient limits the process of regeneration, it probably does so through determining the type of redifferentiation of the dedifferentiated cells and through limiting the extent of dedifferentiation. The indifferent cells which appear on the wound border of the chick, as the result of wound stinuilus, are dominated by the original gradient or gradients to the extent that they redifferentiate only into the germ-layer type from which they sprung.
 +
 +
 +
 +
WOUND HEALING IN THE EARLY EMBRYO 17
 +
 +
SUMMARY
 +
 +
Wounds of the chick blastoderm heal with great facility and the process can be watched for a number of hours in hangingdrop preparations.
 +
 +
In wounds of the extra-embryonic blastoderm all three germ layers take part in the healing process, but the ectoderm and the entoderm are somewhat more active than the mesoderm. As the result of wound stimulus the cells dedifferentiate and all take on the same general appearance and stain reaction. The dedifferentiated cells pile up along the border of the wound, but these indifferent cells of the three germ layers do not fuse and form a healed margin till many hours after the wound has been made. In the inter\'al, before fusion, the masses of the three layers remain separate and advance by amoeboid movement of the individual cells till the opposite wound border is encountered when the two fuse. Later the dedifferentiated cells redifferentiate into cells of the type from which they sprung and wound healing is complete.
 +
 +
Wounds of the embryo heal by dedifferentiation of the ectodermal epithelium and the migration of these cells over the cicatrix. The process is through dedifferentiation, migration by amoeboid movement and redifferentiation into epithelium. There is no regeneration of the underlying parts and the entoderm takes very little part in the process. The directive stimulus which causes the migration of the epithelial cells is probably of a chemico-physical nature and the covering of the wound is effected without the occurrence of cell proliferation.
 +
 +
The wound stimulus is not transmitted from the injured to the uninjured tissue layers in the chick, and even dedifferentiated cells are so Limited in their potentialities that regeneration, in the sense that it occurs in the lower animals, is not observed. It would seem that wound repair is a step or phase of the process of regeneration and that the embryonic dominance is so pronounced that it prevents the wound stimulus from carrying the process beyond this phase.
 +
 +
 +
 +
18 C. W. M, POYNTER
 +
 +
LITERATURE CITED
 +
 +
Barfurth, D. 1894 Experimentelle Untersuchung iiber die Regeneration der Keimbljitter bei den Amphibicn. Anat. Heft., Bd. 3, S. 309-351.
 +
 +
Barfurth, D., Dietrich uxd Dragexdorff, O. 1902 Versuche iiber Regeneration des Auges und der Linse beim Hiihnerembryo. Anat. Anz., Erganz. zum Bd. 21, Ver. der anat. Ges. auf der 16 Versamul. in Halle.
 +
 +
Born, G. 1896 Ueber Verwachsungsversuche mit Amphibienlarven. Arch. f. Entw-Mech., Bd. 4, S. 349-465; 517-623.
 +
 +
Child, C. M. 1915 Individuality in organisms. Univ. Chicago Press, Chicago.
 +
 +
Driesch, H. 1896 Die taktischc Reizbarkeit der Mesenchymzellen von Echinus microtubcrculatus. Arch. f. Entw-Mech., S. 362-380.
 +
 +
Fraisse, p. 1885 Die Regeneration von Geweben und Organen bei den Wirbelthieren, besonders Amphibien und Reptilien. Theodor Fischer, Cassel und Berlin.
 +
 +
Harrison, R. G. 1914 The relation of embryonic cells to solid structures. Jour. Exp. Zool., vol. 17, pp. 521-544.
 +
 +
Holmes, T. J. 1914 The behavior of epidermis of amphibians when cultivated outside the body. Jour. Exp. Zool., vol. 17, pp. 281-296.
 +
 +
Lewis, R. IM., and Lewls, W. H. 1911 The cultivation of tissues from chick embrj'os in solutions of NaCl, CaCl, KCl, and NaHCO. Anat. Rec, vol. 5, pp. 277-293.
 +
 +
Lillie, F. R. 1903 Experimental studies on the development of the organs in the embryo of the fowl. Biol. Bull., vol. 5, pp. 92-123.
 +
 +
McWhorter, J. E., AND Whipple, A. O. 1912 The development of the blastoderm of the chick in vitro. Anat. Rec, vol. 6, pp. 121-139.
 +
 +
MiNOT, C. S. 1908 The problem of age, growth and death. G. P. Putnam's Sons, New York.
 +
 +
Oppel, a. 1913 Demonstration der Epithelbewegung im Explantat vom Froshlarven. Anat. Anz., Bd. 45, S. 173-185.
 +
 +
OsowsKi, H. E. 1914 Ueber aktive Zellenbewegung im Explantat vom Werbeltierembryonen. Arch. f. Ente-Mech,, Bd. 38, S. 547-5^3.
 +
 +
Rand, W. H. 1905 The behavior of the epidermis of the earthworm in regeneration. Arch. f. Entw-Mech., Bd. 19, S. 16-57.
 +
 +
Roux, W. 1894 Ueber die Selbstordnung (Cytotaxis) sich "beruhrender" FurchungszcUcn des Frocheies durch Zellenzusammenfiigung, Zellentrinnung und Zellengleiten. Arch. f. ?]nt\v-Mech., Bd. 3, S. 381-468.
 +
 +
Shorey, M. L. 1909 Differentiation of neuroblasts. Jour. Exp. Zool. vol. 7, pp. 25-63.
 +
 +
 +
 +
PLATES
 +
 +
 +
 +
19
 +
 +
 +
 +
PLATE 1
 +
 +
EXPLANATION OF FIGURES
 +
 +
1 Section through the wound border of the area pellucida. From experiment 170 on chick forty hours old, wound healing of two hours' duration. Left margin shows the indifferent cells of the three cell layers. The tendency to pile up is most noticeable in the ectoderm. X 450.
 +
 +
2 Section through the same wound shown in figure 1, but at a different level. When the three layers have relations which are favorable for fusion, they remain independent of each other. The clear indifferent cells are a constant feature of this stage.
 +
 +
3 Section through wound of experiment 172 in which healing process has proceeded for seven hours. The ectoderm only was wounded and the fissure has filled with indifferent cells so that the line of juncture cannot be discovered. The other cell layers have not reacted to the wound stimulus of the ectoderm.
 +
 +
4 Section through a wound of the extra-embryonic blastoderm which has just closed. Experiment 173 allowed to heal for five hours. Indifferent cells so packed together that it is difficult to distinguish those of the mesoderm. X 450.
 +
 +
5 Section through wound of extra-embryonic blastoderm of experiment 201. Healing has progressed twenty-four hours. Somatopleure and splanchnopleure have fused and entoderm is continuous with ectoderm. At this stage the cell layers have lost the seeming repellence which acted to keep them apart in earlier stage shown in figure 1.
 +
 +
6 Section through wound of same region shown in figure 5, experiment 11; wound repair time, twenty-eight hours. The two plates of mesoderm have fused, but the ectoderm and entoderm are still separate. Except for the migration of the wound border and a somewhat larger number of dedifferentiated cells, the figure is the same as figure 2, indicating a slowing up of the reaction produced by wound stimulus.
 +
 +
7 Section through healed wound from experiment 28. The process of repair has been allowed to continue for fifty-four hours. This is a later stage of the conditions shown in figure 5. The dedifferentiated cells have redifferentiated and it is impossible to discover the line of juncture of the two plates.
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 +
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20
 +
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 +
WOUND HEALING IN THE EARLY EMBRYO
 +
 +
C. W. M. POYXTER
 +
 +
 +
 +
PLATE 1
 +
 +
 +
 +
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COEL
 +
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^v:'=^¥;v^V--so PL
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21
 +
 +
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 +
PLATE 2
 +
 +
nXPLAXATION OF FIGURES
 +
 +
S Photomicrograph .showing transverse section of wound cutting through the splanchnopleure and somatopleure of embryo. The denuded mesenchyme has not yet been covered b.y the ectoderm and the coelom is not closed. Time of healing, five hours. Reduced in publication. X oOO.
 +
 +
9 Photomicrograph from experiment 54, in which healing has proceeded for twenty-four hours. Region same as figure 8. Wound is closed and covered by ectoderm, a few iiulifforcnt colls can be scon where the two mesenchymal plates join.
 +
 +
10 Photomicrogra])li of a transection of the spinal cord after twentyfour hours. The ectoderm has only partially covered the cicatrix of the cord.
 +
 +
11 Photomicrograph of an oblique section of a transected cord. This picture is shown to illustrate the way in which the neural canal closes for some distance beyond the wound. The* cells lining the neural tube come in close contact but the line of juncture is always very distinct.
 +
 +
12 Photomicrograph of a cauterized wound, experiment 67, after fortyeight hours. Section is of the embryonic somatopleure and shows a largeamount of dead tissue Aviiich has not as vet been eliminated.
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22
 +
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 +
WOUND HEALING IN THE EARLY EMBRYO
 +
 +
C. W, M. POYXTER
 +
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PLATE 2
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^ /
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8 T%^
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10
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23
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Resumido por el autor, Ezra Allen.
 +
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I'll iiuHodo para la fijaci6n tie los testiculos de la rata, mediante
 +
 +
ol f'ual se conservan los detalles citol6gicos asi como las
 +
 +
relaciones norniales entre los tiibiilos y los
 +
 +
tejidos intersticiales.
 +
 +
T.a relacion normal entre el tejido intersticial y los tiibulos en el testiculo de la rata puede eonservarse inyectando los vasos sanguineos con el fijador "B-15" (descrito en mi trabajo acerca de los Experimentos sobre Tecnica, (16) ), despues de expulsar la sangre con solucion salina normal o con soliicion de Locke. Una presion de 15 a 20 mm. de mercurio es suficiente para la inyecci6n. Para conocer la presion se une el frasco de presi6n con un manometro de mercurio, comprimiendo el liciuido por medio de una pera de goma, vertiendo agua gota a gota o mediante el aire comprimido. Tan pronto como los testiculos se endurecen, se separan del cuerpo del animal y se colocan en el liquido fijador templado, durante treinta a sesenta minutos, al cabo de los cuales se cortan en rodajas de 2 a 4 mm. de espesor. Tanto el animal como los liquidosa inyectar deben eonservarse a una temperatura de unos 38°C. durante el proceso de la inyeccion. La deshidratacion, aclaramiento e infiltraci6n se realizaran por cambios muy graduates de los litjuidos empleados, que se verteran gota a gota. Este metodo fija muy bien todos los detalles citologicos, incluso los cromosomas en los estados en que tienden a aglomerarse, Otros organos se fijan tambien muy bien para trabajos citologicos. Para expulsar toda la sangr^ de los rifiones se necesitara una presion algo mayor que la indicada.
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 +
Translated by Dr. 3os6 Nonidez Coliimbi.'i University
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ACTHOK S ABSTRACT OF THIS PAPER ISSUED BY THE BIBIJOGR.\PHIC SERVICE, FEBRT-VRY 24
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A TECHNIQUE WHICH PRESERVES THE XOR^IAL CYTOLOGICAL CONDITIONS IN BOTH GER.MINAL AND INTERSTITIAL TISSUE IN THE TESTIS OF THE ALBINO RAT (MUS NORVEGICUS ALBINUS)
 +
 +
EZRA ALLEN
 +
 +
T?ie Wistar Institute of Anatomy and Biology and the Zoological Laboratory of the University of Pennsylvania
 +
 +
ELEVEX FIGURES
 +
 +
In a recent paper (Allen, '16), I described a method by which the c}i:ological details of the germ cells in the albino rat might be demonstrated. WTiile this method is successful for the purpose named, it does not preser\'e the normal relationships between the tubules and the interstitial tissue. This tissue is torn away from the tubules and distorted. These effects are shown in figures 3, 5, and 7. The normal conditions appear in figures 4, 6, and 8. Interstitial tissue in the rat testis is much less in relative quanity than in most mammals, and is so delicate that if the notoriously impermeable tunica albuginea is ruptured to admit the fixing fluid freeh', the interstitial tissue is badly torn.
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 +
The purpose of this paper is to describe a method by which the normal histological and c}i:ological relationships of the two tissues involved may be preser\-ed. It is pubHshed with the hope that it may also be of service in suggesting a solution of similar problems in other tissues. A list of reagents and apparatus will be given and then a description of their use. An extended experience has shown that no detail may be omitted in the process without danger to the material, and for that reason the description of reagents and processes is full.
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26 EZRA ALLEN
 +
 +
REAGENTS AND APPARATUS
 +
 +
Reagents
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Washing fluid for removing the blood: either 0.9 per cent salt or Locke's solution. Fixing solution:
 +
 +
A. Picric acid, saturated aqueous solution 75.0 cc.
 +
 +
Formal, chemically pure 25.0 cc.
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Glacial acetic acid 10.0 cc.
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 +
B. Chromic acid, crystals, C.P 1.5 grams
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 +
Urea, crystals, C.P 2.0 grams
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 +
To prepare: Mix the reagents under A and warm to 38°C. in a closed vessel. Then stir in the chromic acid until completely dissolved ; after which add the urea, stirring while it is being added. The resulting fluid should be transparent and rather dark brown in color. If a white precipitate forms, the difficulty is doubtless with the formalin. Ordinary commercial formalin is almost certain to produce this result. That put up by Schering never gave this trouble. The representatives of this firm are now putting out a product that seems about equal for this purpose to that formerly imported. If the solution is turbid, the fault may lie %\"ith either the formalin or the chromic acid. This latter should be as nearly equal in quality to the Kahlbaum as may be obtained. Deep red crystals have proved satisfactory.
 +
 +
After standing an hour or thereabouts, the fluid will turn green on account of the formation of chrome acetate, when it is not as effective for fixation as before.
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 +
Other reagents
 +
 +
5 per cent, 10 per cent, 50 per cent, and 70 per cent alcohol.
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 +
Saturated aqueous solution of lithium carbonate.
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Analin oil, C.P.
 +
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Synthetic oil of wintcrgreon (methyl salicylate), C.P.
 +
 +
52° or 50° paraffin — the lower temperature is preferable.
 +
 +
The anilin oil should be nearly colorless. If doubt exists as to its purity, it should be distilled, when it will be practically colorless. A slight discoloration does not stain the tissue detrimentally.
 +
 +
Too great care cannot be taken to see that the chemicals are pure.
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CYTOLOGICAL CONDITIONS IN TESTIS OF ALBINO RAT 27
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Apparatus for injection
 +
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1 Woulff bottle of about 500 cc. fitted with three necks and one-hole rubber
 +
 +
corks ,
 +
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2 200-cc. bottles (preferably aspirator) for the washing and fixing fluids, fitted
 +
 +
with perforated rubber corks. Either an atomizer bulb or a large supply bottle (preferably aspirator) for holding
 +
 +
the water which will supply the pressure. If not of the aspirator type, this
 +
 +
will need to be fitted with a siphon, and the same is true of the 200-cc.
 +
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bottles. 1 glass U-tube.
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Rubber tubing and short pieces of glass tubing for connections. Clamps for rubber tubing (six usually suffice). Those of hard rubber, through
 +
 +
which, the tube passes, are most easily used. Their outline is shown in
 +
 +
figure 1. One or more glass cannulae adapted to the rat's thoracic aorta, with an opening
 +
 +
of a millimeter. Or a heart cannula, which may have an opening of 2 or 3
 +
 +
mm. 1 mercury manometer. For this a U-shaped tube may be made of small glass
 +
 +
tubing, as shown in figure 1. The arms should be long enough to allow a
 +
 +
movement of 20 mm. of the mercury coliunn in each. A scale for reading the manometer. This is easily made from paper rules in
 +
 +
millimeters. 1 thermometer. 1 dissecting pan. 1 vessel for holding warm water, through which the rubber tube carr5ang the
 +
 +
injecting fluids will pass.
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Apparatus for treatment of tissue after injection (Allen, 16)
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 +
Either a mechanical agitator for agitating the fluids during dehydration, or
 +
 +
a current of air which is passed through the fluids, thus mixing them
 +
 +
quickly and thoroughly. This latter may be obtained from a pressure
 +
 +
bottle (fig. 2). Bottle for holding the alcohols and oils. While aspirator bottles are preferable,
 +
 +
the fluids may be siphoned through the necks of ordinary bottles. Two or three short tubes drawn at one end to a capillary size. These are to
 +
 +
control the flow of alcohol and oils while they are being dropped (fig. 2). The rate of dropping may be controlled by a faucet, as shown in figure 2, or by
 +
 +
the size of the capillary tube or by a plug of cotton. Paraffin water-bath or a carbon filament electric bulb of about 50 candle-power,
 +
 +
which will melt the paraffin.
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28
 +
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 +
 +
EZRA ALLEN
 +
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 +
 +
DETAILS OF THE METHOD
 +
 +
Injecting. For this purpose, the pressure-bottle apparatus rather than the s^Tinge has been employed, since the pressure required is low, and by this method it may be measured and controlled. The Woulff bottle serves as the reservoir for compressed air. The pressure may be obtained either from a bulb, as shown in figure 1, or from a cun'ent of water flowing into the reservoir from a height sufficient to produce a pressure of 20 to 25 mm. of
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 +
 +
 +
Fig. 1 Injecting apparatus. Instead of the atomizer bulb shown in this figure, pressure may be obtained from an elevated bottle of water connected by tubing to the Woulff bottle. See figure 2.
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 +
 +
mercury against the rat's resistance. The height required is about 2 feet. This method of securing the pressure is shown in figure 2, W. B.
 +
 +
The injecting apparatus is shown in figure 1, which demontrates the mode of connecting the bottles. A T-tube of glass is inserted in the delivery tube. By this means air bubbles or excess of fluid may be discharged. The rubber tube which connects the T-tube with the cannula should be as short as will permit of use. I have found that 8 inches is long enough.
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CYTOLOGICAL CONDITIONS IN TESTIS OP^ ALBINO RAT 29
 +
 +
Test the apparatus for freedom of flow. Avoid any air bubbles in the injecting fluids. The longer portion of the tube conveymg these fluids is passed through a vessel containing warm water, so that the injecting fluid may be discharged from the cannula at about 38°C. The quantity of water should be a quart or two, and should be held at a temperature which will maintain the 38°C. point at the cannula when the injecting fluid is flowing slowly. To preserve this temperature, as well as for another reason stated below, it is desirable to have the tube between the T-tube and the cannula as short as possible.
 +
 +
During the process of injection the rat should be kept warm. This may be accomphshed by placing the dissecting pan over a deep tray of equal size, in which hot water has been placed. Or the tray may be warmed on an electric heater.
 +
 +
"When all is in readiness, the rat is lightly anesthetized by either chloroform or ether. It is important that the heart be beating or that it has just stopped beating, as in many cases a brief delay after the heart stops seems to interfere with the free passage of the washing fluid at the low pressure employed. I have injected through the thoracic aorta rather than the heart. To expose this vessel, an incision is made from the penis to the anterior ribs, severing the ribs a little to the left of the sternum. A second incision is made at right angles to the first, just posterior to the ribs, and the diaphragm cut on the left side so that the thorax on that side may be thrown open by bending the ribs back and breaking them. After removing the slight amount of fat about the artery, the cannula is inserted, care being taken that a slight flow of the washing fluid is maintained in order to prevent air bubbles. As soon as the cannula is secured in place, I increase the pressure gradually but quickly until the vena cava is well filled at a part just anterior to the liver. The vena cava is then cut at this point and the pressure turned on full — 20 to 25 mm., counting the sum total of the movement in both arms. As washing proceeds, I watch the intestines and liver. Usually by the time the former are cleared of blood and the latter is beginning to pale, the "testes have been thoroughly washed out. It is well, however, as a final test, to examine the testes by pulling
 +
 +
 +
 +
30 EZRA ALLEN
 +
 +
thcni into the body cavity (if not already retracted), and noting whether they are white. During the injection of both the washing and fixing fluids it seems advantageous to let the testes lie within the scrotum.
 +
 +
When washing is seen to be complete, the tube is changed from the washing bottle to that containing the fixing solution. The excess of washing fluid is washed out of the discharge tube through the ann of the T-tube designed for that purpose, as previously noted, without removing the cannula from the artery. At the same time any air bubbles which may have entered with the fixative may be passed out by the same channel. During this changing, the clamp between the T-tube and the cannula has been closed. As soon as this clamp is removed the fixative will begin to flow toward the animal. This fluid will mix in the short tube between the T-tube and the cannula, but since its capacity is so small the fixing fluid at full strength almost immediately replaces the washing fluid, a ^'e^y important consideration if good fixation is to be secured.
 +
 +
If the rat is large, the fixative should flow until about 100 cc. has been used. X less quantity will be sufficient for smaller rats. The picric acid quickly changes the color of the feet and the intestines, so that the progress of the fixative is easily observed. It is well to let the flow continue until the testes feel quite hard, which will usually be their condition after about 75 or 100 cubic mm. of fixing fluid has passed through. As soon as hard, the testes are removed from the body withovit cutting the tunica albuginea.
 +
 +
HARDENING AND DEHYDRATION
 +
 +
The subsequent steps are as important as the process of injection. Injection has been employed to secure quick and thorough distribution of the fixative throughout the organ without rupturing the tunic. The next problem is to maintain the fixation through the subsequent chtinges of fluids. The connective tissue holding the tubules together is so delicate that it is very easily torn by sudden changes. Ry proceeding from one fluid to another very gradually, this disaster is avoided. One method is described below. Others perhaps simpler may be found later.
 +
 +
 +
 +
CYTOLOGICAL CONDITIONS IX TESTIS OF ALBINO RAT
 +
 +
 +
 +
31
 +
 +
 +
 +
To complete the hardening of the testes, they are placed immediately upon removal from the body in fresh fixative at 38°C., where the}' remain at that temperature for thirty minutes, after which they are cut into pieces of about 4 nmi. thick or less by the blade of a safety razor, and the process of dehydration begun.
 +
 +
This is canied on by the drop method. That is. the fluid to be added is transfeiTed drop by drop to the fluid in which the tissue lies. By keeping the mixture thus produced in constant motion,
 +
 +
 +
 +
/=^^
 +
 +
 +
 +
 +
<Air
 +
 +
 +
 +
K\\\\\^^\\\\\\\\\\\\\1
 +
 +
 +
 +
Drying hottle
 +
 +
 +
 +
Fig. 2 Dehydrating apparatus. P.B., pressure bottle; <S'.. siphon; S.d., siphon discharge; S.B., supply bottle for alcohol or oil; W .B., water bottle; C, container for tissue. See Allen ('16).
 +
 +
 +
 +
these drops are rapidly and intimately mixed ^^•ithout exposing the tissue to a sudden difference of densitj' or flow of fluids. The agitation is so gentle that the tissues need not be moved by the currents. ('Allen, '16.)
 +
 +
Dehydration is accompUshed by the following steps: iroiw the fixing solution the tissue maj' be transferred directly to 5 per cent alcohol without injury. It may remain in this fluid for 45 minutes, after which the dropping of the 10 per cent alcohol into the 5 per cent is started. To this 10 per cent alcohol a small
 +
 +
THE .ANATOMICAL RECORD, VOL. 16, NO. 1
 +
 +
 +
 +
32 EZRA ALLEN
 +
 +
quantity (say, 1 per cent) of a saturated solution of lithium carbonate has been added. This salt hastens the removal of the picric acid. After the mixture has reached a strength of 10 per cent alcohol, it may remain for one or two hours, agitation being maintained, and a few drops of lithium carbonate solution may be added from time to time by a pipette; or the mixture of 10 per cent alcohol and lithium carbonate be dropped in as previously,
 +
 +
but ver\^ slowly one drop in ten seconds. At the expiration
 +
 +
of the two hours, change the tissue into fresh 10 per cent alcohol and begin dropping in 50 per cent alcohol and about 1 per cent lithium carbonate solution, about one drop per second, until enough of the mixture is added to l)ring the fluid up to 30 per cent alcohol, and in this strength the tissue should remain for about an hour.
 +
 +
Determination of the strength of alcohol in which the tissue will lie after such a dropping process may be made by estimating the quantity of the new fluid, to be added to that of the lower percentage, which will be required for the purpose, and this quantity placed in the sup])ly bottle.
 +
 +
From the 30 per cent alcohol, the tissue is to pass to a mixture of equal parts of 50 per cent alcohol and anilin oil. By experiment it has been found that this is as high a concentration of anilin as will mix well with 30 per cent alcohol. This mixture should be added in very small drops and at the rate of not more than one in five seconds. If a precipitate appears after the flow has continued for a few minutes, it is a sign that the fixing fluid has not been entirely removed from the tissue, which must then be returned to the 30 per cent alcohol and lithium carbonate for a longer period.
 +
 +
When the new mixture reaches the stage of equal parts of anilin and 50 per cent alcoliol the next fluid should be started, which is equal parts of anilin and 70 per cent alcohol, dropped as slowly as before. WTien the ne^^■ mixture reaches the stages of this last fluid, the tissue is changed to fresh 70 per cent and anilin, and pure anilin is started dropping at the rate of about one drop in ten seconds. If the drop is reduced to the minimum in size, the rate may be one in five seconds. The anilin is so much heavier than
 +
 +
 +
 +
CYTOLOGICAL CONDITIONS IN TESTIS OF ALBINO RAT 33
 +
 +
alcohol that the exchange must take place very slowly. It may well require twelve to fourteen hours, so that this part of the process may take place during the night. Dehydration will be complete when the tissue is clear like amber and has been passed through one change of pure anilin.
 +
 +
It should be stated that at the time of changing from one fluid to another higher in alcohol or anilin content, the tissue should be placed in fresh fluid of the strength to which it has arrived, as stated definitely in the step from 5 per cent alcohol to 10 per cent, and again in the step to anilin.
 +
 +
CLEARING AND INFILTRATING WITH PARAFFIN
 +
 +
The clearing oil should be added by the same method as that used for the alcohol and anilin. It is important to remove all of the anilin from the tissue in order that the paraffin may infiltrate thoroughly-. For clearing, I have found the sjTithetic oil of wintergreen more satisfactory for the rat testis than any other clearing agent, although the cedar-wood oil is also very excellent.
 +
 +
The mixing of paraffin with any clearing oil is difficult if the necessary shrinkage of the specimen incident thereto is to be gradual. For this reason the paraffin must be added slowd3^ I have found that carefully graduated strengths of a mixture of the oil and paraffin give very satisfactory results. The steps employed have been eight, beginning with 10 per cent melted paraffin in wintergreen oil, then 20 per cent, 30 per cent, 40 per cent, 50 per cent, 60 per cent, 80 per cent, 90 per cent, and finally pure paraffin, keeping the tissue warmed to the necessary- temperature during these changes. It is better to err on the side of too gradual than too sudden a progress. Not less then two hours should be consumed in this process. Four or five changes of paraffin, requiring two or three hours, are then necessary to remove all traces of the oil.
 +
 +
Up to the present time I have used no method of agitating the oil durmg the addition of the paraffin, and consequently have not attempted to employ a dropping mechanism in the paraffin oven. The oil of wintergreen is so much heavier then melted paraffin that it does not mix readih- without agitation. A dropping and
 +
 +
 +
 +
34 EZRA ALLEN
 +
 +
agitating mechanical device might be devised for working at a temperature required for melted paraffin.
 +
 +
IMBEDDING AND SECTIONING
 +
 +
The remaining steps of imbedding and sectioning are carried on as usual. The sections should be spread to the limit by heating them to a degree just below the melting-point. Overhead electrical heat is preferable to the flame for this purpose. It is easily employed by using a rather high-power carbon filament bulb (50 candle-pc^wer) in a reflector. If the slides are supported on glass rods or'other small framework rather than laid directly upon the table, the paraffin spreads more slowly and there is very little danger of overheating the material. A temperature control is readily supplied by an extra slide upon which some of the waste .paraffin sections are floated. "\Mien spreading is thus complete, the water should be drained off and the sections oriented if necessary. While dr>dng, the sHdes should be kept as warm as possible without melting, in order to prevent the slight shrinkage of tissue which occurs if the sUdes dry cold. Both the spreading and drying may be carried in paraffin ovens properly regulated in temperature for each procedure.
 +
 +
RESULTS
 +
 +
The figures show that by the method described the dehcate interstitial tissue is retained in its normal position attached to the limiting membranes of the tubules: that the cytological details of the cells in both tubules and interstitial tissue are also retained.
 +
 +
In normal rats no extravasation has been observed, nor stretching of the vascular walls. In some rats in poor condition extravasation has occurred.
 +
 +
If the washing fluid is run for a longer time than necessary to wash out the testes, each of the internal organs in the abdominal cavity will be freed from blood and may be used for cytological purposes . The kidneys may require a little higher pressure. The method preserves the wall of the alimentary canal very well, preserving with extreme delicacy the central portion of the villi.
 +
 +
 +
 +
CYTOLOGICAL CONDITIONS IN TESTIS OF ALBINO RAT 35
 +
 +
With this tissue it is well to remove a portion of the intestine while the low pressure is still on and inject the lumen with the fixing fluid by means of a pipette, and then drop the piece into the fixing fluid and treat as described for the testis. The division figures in the mucosa cells are thus very well differentiated.
 +
 +
LITERATURE CITED
 +
 +
Allen, E. 1916 Studies on cell division in the albino rat. II. Experiments on technique, with description of a method for demonstrating the cytological details of dividing cells in brain and testis. Anat. Rec, vol. 10.
 +
 +
 +
 +
PLATE 1
 +
 +
 +
 +
EXPLANATION OF FIGURES
 +
 +
 +
 +
The figures are photomicrographs made with a Zeiss projection ocular, a Watson condenser, and objectives chosen according to the magnification desired. They were all reduced one-third in reproduction. The sections were cut at In.
 +
 +
3 and 5 Sections of testis fixed by cutting the organ into small pieces with scissors. Stained with iron haematoxylin. X 47.
 +
 +
4 and 6 Sections of testis prepared by the method here described. Stained with iron haematoxylin and acid fuchsin. X 47.
 +
 +
7 Portion of interstitial tissue from the same section as figure 3. Stained with iron haematoxylin. X 667.
 +
 +
5 Interstitial tissue from same preparation as shown in figures 4 and 6. The glandular and endothelial nuclei are prominent. The dark line running up and down in the figure is the membrana limitans out of focus. The interstitial takes the stain much more deeply than the germinal tissue. Stained with iron haematoxylin and acid fuchsin. X 667.
 +
 +
9 Germinal tissue, showing chiefly first spermatocytes in late prophase and metaphase. From same section as figures 4 and 6. X 333.
 +
 +
10 and 11 Two cells from same portion of tissue shown in figure 9 photogra|)hod under the oil-immersion lens to show fixation of the chromosomes in metaphase. X 667.
 +
 +
 +
 +
36
 +
 +
 +
 +
CYTO LOGICAL COXDITIOXS IN TESTIS OF ALBINO RAT
 +
 +
EZRA ALT,EN
 +
 +
 +
 +
PLATE 1
 +
 +
 +
 +
 +
 +
 +
X
 +
 +
 +
 +
 +
 +
 +
 +
 +
 +
5
 +
 +
 +
 +
 +
 +
 +
 +
6
 +
 +
 +
 +
 +
§
 +
 +
 +
 +
m"^
 +
 +
■j^^ r
 +
 +
 +
 +
-^
 +
 +
1
 +
 +
 +
 +
 +
• ^
 +
 +
 +
/• • *
 +
 +
 +
->.^
 +
 +
 +
 +
-^
 +
^ t
 +
 +
 +
«:^
 +
 +
 +
 +
 +
.^.
 +
 +
 +
 +
 +
"^. >
 +
 +
 +
..it
 +
 +
 +
 +
 +
 +
„^
 +
 +
8
 +
 +
 +
 +
'■ '^
 +
 +
 +
4 ■•■
 +
 +
 +
 +
ft
 +
 +
 +
 +
 +
 +
 +
 +
 +
 +
 +
f
 +
 +
 +
 +
 +
-^^■.
 +
 +
 +
m
 +
 +
 +
1
 +
 +
 +
 +
 +
II ' ^
 +
 +
 +
 +
 +
 +
Resumido por el alitor, Harrison H. Hunt.
 +
 +
Las variaciones de la vena tiroidea inferior del gate domestico.
 +
 +
La \ona tiroidea inferior vierte la sangre que conduce en cualquiera de las siguientes venas: innominada izquierda, yugular interna izciuierda, innominada derecha, Aiigular externa derecha, yugular interna del mismo lado y precava. En uno de los casos la \'ena tiroidea inferior se dividia en su extremo posterior en dos ram as una de las cuales entraba en la \'ena innominada derecha, la otra en la izquierda. Proximamente en la mitad de los gatos estudiados la tiroidea inferior se vertia en la innominada izquierda. En su extremo anterior la vena en cuesti6n, generalmente, aunque no siempre, se divide dicotomicamente. Generalmente esta ramificacion esta situada entre los lobulos de la glandula tiroides, auncjue en algunas ocasiones, se presenta en el mismo nivel que el extremo anterior de la glandula tiroides o posteriormente a dicha glandula.
 +
 +
Translated by Dr. Jos6 Xonidez Columbia University
 +
 +
 +
 +
aithor's abstract of this paper issued by the bibliographic service, february 24
 +
 +
 +
 +
THE VARIATIONS OF THE INFERIOR THYROID VEIX OF THE DOIVIESTIC CAT
 +
 +
HARRISOX R. HUNT
 +
 +
West Virginia University
 +
 +
SEVEX FTGFRES
 +
 +
The inferior thyroid veins of man vary considerabh^ The following obser^^ations, made on thirty-three domestic cats selected at random, show that the same is true of this vein in the cat. Each of the accompanying figures represents, somewhat diagrammatically, the conditions in a single animal. These seven animals suffice to give a fairly complete idea of the variations in the remaining twenty-six.
 +
 +
Figure 1 shows the inferior thjToid vein (1) communicating anteriorh^ with the left internal jugular, receiving branches from only the left lobe of the thjToid gland {14), then passing obhciuely backward across the trachea {13) to join the right innominate vein (10). The veins labeled 2 and 3 in this and the following figures were not homologized with certainty with the human superior and middle th\Toid veins. Two other dissections resembled figure 1 very closely, except that in one of them the inferior thyroid vein joined the external jugular vein at a.
 +
 +
Figure 2 resembles figure 1 in some respects. However, the inferior th}Toid vein {!) in figure 2 receives a branch (a) from the right lobe of the thyroid gland {1^), empties into the right internal jugular vein (4), but in the dissection did not appear to communicate directly with the left internal jugular. The inferior thyroid vein in a second cat joined the jugulars at m
 +
 +
39
 +
 +
 +
 +
40 HARRISON R. HUNT
 +
 +
(fig. 2), and its transverse branch (fig. 2, a) could not be traced as far as the right lobe of the thyroid gland. In a third indi\idual, vessels a and 3 (fig. 2) were connected by a conspicuous vessel running along the dorsal surface of the right lobe of the thyroid gland, and the inferior thyroid vein entered the right innominate at n (fig. 2). In all other respects the inferior thyroid veins in these three cats were very similar.
 +
 +
In one case (fig. 3) the inferior thyroid vein (/) was formed by the union of a branch (2) from each of the internal jugular veins (4 and 5). The inferior thyroid, after receiving branches from the right lobe of the thyroid gland (14), passed obliquelj^ backward, joining the left innominate vein (11) near its union with the precava.
 +
 +
The resemblance between the inferior thyroid veins (1) in figures 3 and 4 is evident. However, in figure 4 the inferior tln-roid apparently was unconnected, at its anterior end, with the internal jugular veins; it lay close to the left lobe of the thyroid gland; and its junction with the left innominate vein was considerably anterior to the junction shown in figure 3. A small vein (fig. 4, 15) ran along the dorsal side of the left lobe of the thyroid gland parallel to the inferior thyroid vein (1), connecting anteriorly and posteriorly with the latter vessel. One other cat showed practically the same conditions as those represented in figure 4, though the vein 15 (fig. 4) was not found, and the inferior thyroid vein emptied into the innominate at a (fig. 4).
 +
 +
In figure 5 the two vessels uniting to form the inferior thyroid vein (1) passed backward a short distance before coming together, Th(> inferior thyroid vein was median in position, receiving small side branches from both lobes of the thyroid gland {14)- Except for the fact that 16 and 15 (fig. 4) lay on opposite sides of the trachea, their locations and courses were quite similar. In four other individuals the inferior thyroid vein strongly resembled the same vein in figure 5, though in one case it joined the precava at e (fig. oj.
 +
 +
 +
 +
INFERIOR THYROID VEIN OF DOMESTIC CAT
 +
 +
2 a
 +
 +
 +
 +
41
 +
 +
 +
 +
 +
EXPLANATION OP FIGURE NUMERALS
 +
 +
 +
 +
/, inferior thyroid vein; 2 and 3, branches of the internal jugular veins; 4 right internal jugular vein; 5, left internal jugular vein; 6, right external jugular vein; 7, left external jugular vein; 8, right subclavian vein; 9, left subclavian vein; 10, right innominate vein; 11, left innominate vein; 12, precava; 13, trachea; 14f thyroid gland. (For the significance of 15, 16, and the letters, see text.)
 +
 +
 +
 +
42 HARRISON R. HUNT
 +
 +
In the animal from which figure 6 was drawn a vein ran backward near the medial margin of each lobe of the th>Toid gland m), the two veins uniting at the level of the isthmus of the gland. One of these vessels (2) branched off from the right internal jugular vein. The inferior thyroid vein (1) emptied into the innominate where the external jugular and subclavian veins joined (8). The variations of the inferior thyroid vein in thirteen more cats can best be described by reference to the lettering in figure 6. In twelve of these animals the vein branched at approximately the following points : in one case at a (the branching thus closely resembling the branching of the inferior thjToid vein in fig. 5) , in four cases at c, in six animals at the place where the inferior thyroid vein branches in figure 6, and in one animal as far back as d. The approximate points at which the inferior thyroid vein in these thirteen cats emptied into the innominate and external jugular veins varied greatly (fig. 6). In four cases this union was at o, in four cases at n, in two at I, and in three cases at the points e, h, and i, respectively. In two of these individuals the left anterior branch could be traced to the left internal jugular vein; in two cases, including the animal shown in figure 6, the right anterior branch came from the right internal jugular vein.
 +
 +
Incomplete records of the inferior thyroid veins in four animals show that the vein emptied on the right side in three of them, and into the left internal jugular in the fourth animal.
 +
 +
Figure 7 represents the posterior end of the inferior thyroid vein (1) in one animal. The anterior portions of the vein were not drawn. The vessel divided into two branches which joined the innominate veins {10 and 11) at the places shown in the figure.
 +
 +
Possibly some very small veins emptying into the inferior thyroid vein were not well injected in all the cats examined, thus escaping observation. This might explain the failure in many cases to find connections between the inferior thyroid and internal jugular veins near the anterior end of the thyroid gland.
 +
 +
 +
 +
INFERIOR THYROID VEIN OF DOMESTIC CAT 43
 +
 +
TABLE 1
 +
 +
 +
 +
Inferior thyroid vein unbranched at its anterior end
 +
 +
Inferior thyroid vein divided into two branches at the anterior end of
 +
 +
t he thyroid gland
 +
 +
Inferior thyroid vein divided into two branches at varying positions
 +
 +
between the lobes of the thjToid gland
 +
 +
Inferior thyroid vein dividing into two branches posterior to the
 +
 +
thyroid gland
 +
 +
 +
 +
NUMBER OF CATS
 +
 +
 +
 +
3
 +
 +
6
 +
 +
17
 +
 +
1
 +
 +
 +
 +
TABLE 2
 +
 +
 +
 +
 +
 +
NUMBER OF CATS
 +
 +
 +
Inferior thvroid vein emptying into left innominate
 +
 +
 +
17
 +
 +
 +
Inferior thyroid vein emptying into the left internal jugular
 +
 +
 +
1
 +
 +
 +
 +
 +
 +
 +
Number of cases in which the vein emptied on left side
 +
 +
 +
■ 18
 +
 +
 +
Inferior thyroid vein emptying into right innominate
 +
 +
 +
6
 +
 +
 +
Inferior thyroid vein emptying into right external jugular
 +
 +
 +
3
 +
 +
 +
Inferior thyroid vein emptying into right internal jugular
 +
 +
 +
]
 +
 +
 +
Inferior thyroid vein emptying on the right side (exact position not noted)
 +
 +
 +
3
 +
 +
 +
 +
 +
 +
 +
Number of cases in which the vein emptied on the right side
 +
 +
 +
13
 +
 +
 +
Inferior thyroid vein emptying into precava
 +
 +
 +
1
 +
 +
 +
Inferior thyroid vein emptying into both innominate veins
 +
 +
 +
1
 +
 +
 +
 +
 +
 +
 +
 +
SUMMARY
 +
 +
The results of this investigation may be summarized best in tabular form. Table 1 shows the variation in the dichotomous branching of the inferior thyroid vein at its anterior end. Table 2 summarizes the variations of the point at which the vein emptied posteriorly into the larger veinous trunks.
 +
 +
Thus the inferior th>Toid vein in the majority of cases branches between the lobes of the thyroid gland and enters the larger veins on the left side.
 +
 +
 +
 +
Morgantown, West Virginia, November 22, 1918.
 +
 +
 +
 +
w^^
 +
 +
 +
THE AXATOMIC.VL RECORD, VOL. 16, NO. 2 APRIL, 1919
 +
 +
 +
 +
Resumido por el autor, Eben James Carey.
 +
 +
Estudios teratol6gicos.
 +
 +
A. Sobre un phocomelus, con especial menci6n de las extremidades. El caracter principal de esta clase de monstruos es un acortamiento anormal y cesaci6n del desarrollo de algunos o todos los huesos largos de las extremidades. El presente estudio re\'ela el hecho de que en ausencia completa o desarrollo rudiment ario de una parte del esqueleto, se encuentra tambien una fait a completa o parcial de los musculos relacionados con el. Lo in verso es tambien cierto, pues un excesivo desarrollo de las partes esqueleticas esta acompanado por un grado mayor de desarrollo en los musculos relacionados con ellas. B. La forma externa de un embri6n humano anormal de veintitres dias. El autor da una detalla da descripci6n de la forma externa de este embri6n y una descripci6n de la interesante malf ormacion de la region cervical. El estado de desarrollo de la forma exterior coloca a este embri6n entre el descrito por Bremer, de 4 mm. de longitud y 21 dias de edad, y el descrito por Mall, de 7 mm. y 26 dias, de modo que la edad probable del que se describe es 23 dias. C. y D. Las anomalias de los monstruos anencefalicos : cranioraquisquisis completa. El hecho mas interesante con relacidn a los monstruos anencefalicos, ya notado por varios observadores, es que generalmente pertenecen al sexo femenino. Las anomalias bien marcadas, que se describen en los presentes estudios, son: la falta de cerebro, generalmente tambien de medula espinal y la falta de desarrollo de los huesos que integran la b6veda craneal y la lamina de la columna vertebral. La boca tipicamente abierta de los monstruos anencefalicos esta relacionada con la falta de la b6veda craneal y la perdida correspondiente de la porci6n anterior del musculo temporal. Las disecciones revelan tambien la existencia de una interrelaci6n definida entre el desarrollo de los tejidos 6seo y muscular.
 +
 +
Translation by Josd F. Nonidez Columbia University
 +
 +
 +
 +
atthor's abstract of this paper issued bt the bibliographic service, march 17
 +
 +
 +
 +
TERATOLOGICAL STUDIES
 +
 +
A. ON A PHOCOMELUS, WITH ESPECIAL REFERENCE TO THE
 +
 +
EXTREMITIES
 +
 +
B. THE EXTERNAL FORM OF AN ABNORMAL HUMAN EMBRYO OF
 +
 +
TWENTY-THREE DAYS
 +
 +
C. THE ANOMALIES OF AN ANENCEPHALIC MONSTER.
 +
 +
COMPLETE CRANIORRHACHISCHISIS
 +
 +
D. A SECOND ANENCEPHALIC MONSTER. COMPLETE
 +
 +
CRANIORRHACHISCHISIS
 +
 +
EBEN J. CAREY
 +
 +
Department of Anatomy, Creighton Medical College, Omaha, Nebraska
 +
 +
SEVENTEEN FIGURES
 +
 +
ACKNOWLEDGMENTS
 +
 +
1 wish to express my sincere thanks to Drs. Alonzo Mack, J. S. Foote, T. J. Dwyer, and C. J. Nemec, for the specimens herein studied, and to Dr. A. F. Tyler, for the skiagraphs of the skeletons, and would also acknowledge the helpful interest and suggestions of Prof. H. von W. Schulte, Director of the Department of Anatomy in this school.
 +
 +
A. ON A PHOCOMELUS WITH ESPECIAL REFERENCE TO THE
 +
 +
EXTREMITIES
 +
 +
The term phocomelus is derived from the Greek cf) u x v, seal, and iJL k\ s, limb. The chief characteristic of monsters belonging to this class is an abnormal shortening and arrest of development of some or all of the long bones of the extremities. The feet and hands are usually composed of the normal number of skeletal elements, but generally appear to arise directly from the
 +
 +
45
 +
 +
 +
 +
46 EBEN J. CAREY
 +
 +
pelvic and shoulder-girdles, respectiveh', which lends them the fantastic appearance of a seal's flippers.
 +
 +
The specimen described was obtained by Doctor Mack, Professor of Obstetrics, Creighton ]\Iedical College, February, 1917. It was a full-term, still-bom fetus, and parturition was marked by excessive dystocia. The weight was 2500 grams and the crownrump measurement 25 cm. Through the shoulder and peh'ic regions it measured 12 and 10 cm., respectively.
 +
 +
External form
 +
 +
The marked umbilical hernia, in which the coils of the intestines show through the attenuated walls at the base of the umbilical cord, is readily apparent in figure 1. This is due to arrested development. Xonnally, fi\'e or six primitive intestinal loops, by rapid elongation in embryos between 17 and 20 mm. in length, push their way into the umbilical coelom, producing the normal hernia funiculi umbilicalis physiologica, where they remain until the embryo reaches a length of between 35 and 45 mm. Soon after the latter period the intestinal loops return to the abdominal cavity proper.
 +
 +
The lateral contour of the abdominal and thoracic regions is exceedingly convex, depending upon the excessive size of the Uver. Normally, the liver at term is one-twentieth of the total body weight in the still-bom, Jackson ('09). The liver in this case, however, weighs 490 grams, or about one-fifth of the total body weight. The excessive size of the liver is due to two factors: first the umbiUcal hernia; second, the cleft sternum, both operating to release the liver from the confinement which is nonnally present. The liver in coelossomic monsters, like the brain in cases of hydrocephalus, shows a tendency to assume an unnatural bulk when relieved from the nonnal pressure of relational structures.
 +
 +
In the embryo the ventral wall of the trunk is at first very thin, and the heart with its various parts as well as the liver and other viscera may be seen through it. From the sides the anlagen of the skeleton and musculature grow into the walls: arrest of this growth may occur and ])roduce ectopia cordis and fissura stemi.
 +
 +
 +
 +
TERATOLOGICAL STl'DIES
 +
 +
 +
 +
47
 +
 +
 +
 +
 +
Fig. 1 Phocomeius. ventral view.
 +
 +
Fig. 2 Phooomelus, right lateral view.
 +
 +
Fig. 3 Phocomeius, left lateral view.
 +
 +
Fig. 4 Phocomeius. dorsal view.
 +
 +
 +
 +
48 EBEX J. CAREY
 +
 +
which depend ii])()ii the disturbance in the thoracic region. A portion of the intestine, as noted above, nonnally projects into the lunbihcal cord at the tune that the outward growth of the abdonimal walls occurs. Nonnally, the intestinal hernia recedes into the abdominal cavity with the further development of the abdominal walls, but if the latter are an-ested in their development, the heniia persists, as is seen in this specimen.
 +
 +
The upper extremities are much distorted and resemble in no way, except in the contour of the shoulder and in the digits, the extremities of a nonual full-tenn fetus. The palmar surfaces of the hands are turned mesiad, a retention of the position which is nonnal in embryos of 18 to 25 mm. in length.
 +
 +
The median raphe extending from the anus to the scrotum is well marked. The scrotmn is composed of two fat-filled pouches which do not enclose the testicles. These organs are found in the inguinal canal about read}' to emerge at the external abdominal ring.
 +
 +
The lower extremities also show the degree of rotation characteristic of a normal embryo 18 to 25 nun. in length. The knees are directed ventrolateral, while the jilantar surfaces of the feet are turned mesial and consequently are opj^osed to each other. The dorsum of each foot is unusuallj' high. The abducted position of the great toe and the metatarsal pads are especially clearly seen in the right foot. This is characteristic of embrj'os of about 25 mm. in length. The metatarsal i)ads normally undergo a gradual retrogression and their outlines become indistinct during the fourth and fifth months. The phalangeal pads of the great toe, and in a less degree the second and third toes, of the right foot are clearly shown.
 +
 +
The right upper extremity is best seen in figure 2. The shoulder and wrist are recognizable and a slight groove dorsally in the region of the axilla marks the i)osition of the elbow. The lianb is so placed that the extensor surface is directed laterad. The five digits are distinct; the thumb is certainly i-udimentary. The hand is unusually broad toward the base of the fingers; this is another early fetal characteristic which has been retained.
 +
 +
 +
 +
TERATOLOGICAL STUDIES 49
 +
 +
In the lower extremity the heels are well marked and the foot is extended as a result of the contractm^e of the gastrocnemius muscle: this occasions the talipes equinus variety of club-foot. In addition, the foot is inserted so that the soles are opposed to each other by the contracture of the tibialis anticus muscle, resultmg in the talipes varus variety of the club-foot. This is mereh' arrested development, however, for the position described above is a normal phase of limb rotation and is regularly present in embryos of 35 mm.
 +
 +
The head is abnonnally large: the forehead is especially protuberant. This is partly due to arrested development and parth' to its hydrocephalic condition. The anterior and posterior fontanelles and sagittal suture gape in an abnormal manner because of the distended cerebral hemispheres. The protuberant forehead resembles the condition found in prosencephahc monsters. In addition to hydrocephalus, there is an extensive meningeal hemorrhage incident to labor.
 +
 +
The root of the nose is deeply depressed, and the nose as a whole is very low and broad. The upper lip projects, whereas the lower one recedes. The depression between the root of the nose and forehead is nonnal in embryos between 18 and 42 nun, in length, but later this character is effaced.
 +
 +
The shoulders are distincth' marked, as seen in figure 3. The protuberance due to the acromial process of the scapula is especially distinct on the left side. The disproportion between the segments of the limbs is striking. In each lower limb a dorsal groove is seen which corresponds to the popliteal space. It is at once evident (fig. 4j that the region of the thighs is gi'eatl^' shortened, and a corresponding shortening of the proximal segment of the upper limb is also apparent.
 +
 +
The left lateral aspect is reproduced to show the s\^mnetry of the surface abnonnalities (compare figs. 2 and 4;. Externally a tendency is detectable to subdi\'ision of the upper extremity into ann. forearm, and hands by grooves which lunit these regions. Rudiments of the finger nails may be detected, but these structures have not broken through the overlying epidennis.
 +
 +
 +
 +
50 EBEX J. CAREY
 +
 +
In the lower extremity tlie regional outlines are not as distinct as in the upjier. The area corresponding to the knee is directed cejihalolateral, but there is no definite demarcation between the dorsum of the foot and the leg. The toe nails and toes are not a*^ well developed as the finger nails and the fingers.
 +
 +
The rotundity of the cheeks is quite marked (fig. 4), and welldeveloped sucking pads were found on dissection.
 +
 +
The symmetrical arrest of development of the lower extremities is clearly seen in figure 5.
 +
 +
Internal anatomy
 +
 +
The section of the alimentarj^ canal, contained in the umbilical hernia, consists of the cecum, appendix, 2 cm. of the ascending colon, and 10 cm. of the ileum. The latter possesses a marked ^Meckel's diverticulum, from the apex of which a fibrous strand extends into the cord for some distance, eventually to be lost in its connective tissue. The remaining coils of the small intestine are arranged in the normal manner. Coil no. 1 forms the duodenum; the secondary derivatives of coils nos. 2 and 3 are found in the left hypochondriac region, those of coil no. 4 are found in the right hypochondriac region, while those from coil no. 5 are located in the left iliac fossa. So far the arrangement of the small intestine is normal; however, the derivatives of coil no. 6, instead of occupying the hypogastric region, extend directly to the base of the umbilical cord and enter into the umbilical hernia as noted above.
 +
 +
The liver is nearly three times the size of the organ normally found in still-born infants by Jackson ('09), and the spleen is nearly six times its normal weight. The kidneys and spleen are also found to be overweight. The pancreas, bladder, prostate, and testicles are about the normal size.
 +
 +
The heart is hypertrophied; it is about doul)le the average size. The two lungs are much compressed, being only of about onehalf the normal size. The thymus is double the average weight, whereas the thyroid is about normal. To facilitate comparison with ccMiditions in still-born infants of the tenth month, the
 +
 +
 +
 +
TERATOLOGICAL STUDIES
 +
 +
 +
 +
51
 +
 +
 +
 +
 +
Fig. 5 Phocon.elus. caudal view.
 +
 +
Fig. 6 Phocomelus, skiagraph from in front. Natural position of lin.bs.
 +
 +
Fig. 7 Phocomelus, skiagraph. The arms abducted to show curvature of the radii.
 +
 +
Fig. 8 Phocomelus. Skeleton of the upper extremity.
 +
 +
 +
 +
ol
 +
 +
 +
 +
EBEN J. CAREY
 +
 +
 +
 +
TABLE 1
 +
 +
Rilalivc sizes of Ihc fiial organs of the slill-bont phocoiiu las com/iarcd (o those in still-born infants by Jackso7i
 +
 +
 +
 +
Brain
 +
 +
Thymus
 +
 +
Heart
 +
 +
Right hing
 +
 +
Left lung
 +
 +
Liver
 +
 +
Spleen
 +
 +
Right kidney
 +
 +
Left kidney
 +
 +
Right suprarenal Left suprarenal. . Thyroid
 +
 +
 +
 +
MALE STILL-BORN TENTH MONTH (JACKSON)
 +
 +
 +
 +
Cat. number
 +
 +
 +
 +
71 65 80 69 69 71 70 9 9
 +
 +
 +
 +
26
 +
 +
 +
 +
Per cent
 +
 +
 +
 +
12.91 0.296 0.69 0.9S 0.79 4.81 0.27 0.367 0.341 0.101 0.111 0.111
 +
 +
 +
 +
MALE STILL-BORN PHO COMELUS TENTH MONTH.
 +
 +
TOTAL WEIGHT 2500
 +
 +
GRAMS
 +
 +
 +
 +
Weight.
 +
 +
 +
 +
gra7ns
 +
 +
4.-0.00
 +
 +
12.5
 +
 +
30.0
 +
 +
10.0
 +
 +
10.0
 +
 +
300.0
 +
 +
40.0
 +
 +
25.0
 +
 +
25.0
 +
 +
3.0
 +
 +
3.0
 +
 +
4.0
 +
 +
 +
 +
Per cent
 +
 +
 +
 +
18.00
 +
 +
0.5
 +
 +
1.2
 +
 +
0.4
 +
 +
0.4 12.2
 +
 +
1.6
 +
 +
1.0
 +
 +
1.0
 +
 +
0.125
 +
 +
0.125
 +
 +
0.16
 +
 +
 +
 +
weights of the several organs and their percentage of the total body weight are given in table 1, to which are added the findings of Jackson in his series of still-born infants.
 +
 +
 +
 +
Skeletal and muscular systems
 +
 +
The scapula is peculiar in that it possesses no glenoid articular cavity; in its place there is a large rounded protuberance which fits into a corresponding cartilaginous depression of the humerus. The body of the scapula is ossified, but the vertebral border, inferior angle, coracoid process, and acromion are cartilaginous.
 +
 +
A supraspinous muscle arises from the corresponding fossa, but no omohyoid nor levator anguli scapulae muscles are present. The trapezius and rhomboid muscles arc normally located. From the infraspinous fossa arises an infras]:)inatus and from the vertebral border the teres major and minor take origin. The fibers of the deltoid and trapezius muscles are, for the most part, directly continuous over the spine of the scapula, but there
 +
 +
 +
 +
TERATOLOGICAL STUDIES 53
 +
 +
is a deep fibrous inscription which unites this complex muscle mass to the spine. There is a well-marked cartilaginous supraglenoid tubercle for the attachment of the long head of the biceps; the short head of this muscle arises in common with the coracobrachialis muscle from the joracoid process. Both heads of the biceps, the coracobrachialis and the deltoid muscles, fuse to fonn one large complex which is inserted into the radius, no fibers whatever finding attachment on the humerus. From the infraglenoid tubercle, which is cartilaginous, arises the middle or long head of the triceps ; this is the only representative of the normal triceps muscle, the other two heads being absent.
 +
 +
The humerus is represented b}^ a small, all but shapeless mass of soft cartilage. On its superior aspect it presents a deep articular cavity into which fits the head on the scapula described above. This head is finn and calcified, but no secondary ossification center is present : absolutely no calcification is found in the humeral mass. Xo doubt this difference in density" is the immediate cause for the reversal of curvature at the shoulderjoint, determining the presence of a scapular head and a humeral articular cavity. Caudal to this cavity the humerus is produced into a rounded process of cartilage surrounded by a dense mass of fibrous tissue, upon which is inserted the teres major and minor, supraspinatus and pectoraHs minor muscles. Xo brachiahs anticus muscle is present. A few fibrous strands extend from the pectorahs major and latissunus dorsi, to the dense perichondrium of the humeral mass, but the major part of the insertions of these two muscles are by tendon into the proximal end of the radius.
 +
 +
The common origin of the flexor gi'oup of muscles of the foreann, for the most part, is from the proximal end of the radius. There is a small direct continuit}-, however, on the part of the flexor muscles with the biceps l^y means of muscular slips. Smiiliarly, the extensor gi'ou]3. arising in the main from the j^roximal end of the radius, has dii'ect muscular continuity with the triceps.
 +
 +
The radius is the largest and longest bone of the upper extremity. It is well ossified and bowed in adaptation to the abnormal stresses and strains to which it is subjected. At its upper end it presents a concavocon\ex articular surface which artic
 +
 +
 +
54 EBEN J. CAREY
 +
 +
ulates with the lower convex surface of the humerus. The uhia does not enter into the f(^rniation of the elbow-joint and is merely a cartilaginous l)ar extending from the upper extremitj^ of the radius to the carpus.
 +
 +
The carpal elements, navicular, lunate, triquetral, pisifonn, greater multangular, lesser multangular, capitate and hamate, are each defina)3le. They are, however, nothing but cartilaginous nodules presenting but a very faint resemblance to the normal comj'jonents of the carjnis.
 +
 +
In the metacarpus and i^halanges the nonnal nmnber of elements are present, but they are abnormally shortened, especially the metacarpals. All are in a cartilaginous state except the terminal phalanges in which ossification is beginning at the distal extremities. The proximal articular ends of these phalanges are cartilaginous.
 +
 +
The wrist is extended and the hand is adducted towards the ulnar side. It is interesting to note at this point that the flexor carpi ulnaris and the extensor carpi ulnaris are practically one muscle. At their origins these muscles are inseparable. The former is inserted partly- into the pisiform and partly into the ulnar side of the base of the fifth metacarpal element. The latter muscle is inserted also, on the ulnar side of the base of the fifth metacarpal element. The greater muscular mass of the extensor group combined with the physiological unity of the flexor and extensor carpi ulnaris muscles explains the extended position of the wrist and the inclination of the hand to the ulnar side.
 +
 +
The sternum is widely cleft, indeed, union is present only at its cephalic extremit}-. This point evidently represents the persistent episternal band which has become chondrified. Through this band the clavicles are in direct continuitj^ across the ventral median line. The extent of development of the thoracic walls is comparable to that of an embryo of about 17 mm. in length (Muller, '06). The sternal ends of the lower eight cartilaginous ribs do not extend medialward beyond the midaxillary line, and in this connection it is interesting to note that both the rectoabdominales are absent. It is highly probable that their development was initiated, but that subsequently they degenerated, for
 +
 +
 +
 +
TERATOLOGICAL STUDIES 00
 +
 +
a rectus sheath was found on dissection containing a mass of adipose tissue. The obhque and transversalis are imperfect especially towards the thorax. The nerves of the region appear normal and have the usual course and distribution, so the defect in the skeletogenous tissue would seem to be the important factor in the development of these muscles. Towards the pehis the musculature is more nearly normal. Two small p\Tamidalis are present, extending from the pubis to the rectal sheath, and the caudal portions of the flat muscles are readily defined, but less developed than in a normal fetus at term.
 +
 +
^'entrally between the condyles is a smooth cartilaginous elevation attached to the femur at the site of the patellas trochlea. The inhibition of development here present would seem to be associated with the failure of limb rotation and in particular to the imperfect condition of the quadriceps extensor, which has alike failed to detach the patella and to bring the limb into normal position. The muscle is represented by a small rectus, associated with which are a few fascicuU on each side corresponding to the vastus mediahs and lateraUs. With the latter the gluteus maximus is continuous. Xo traces were found of either the vastus intermedius or the subcrureus. The gluteus medias and gluteus minimus are inserted into the greater trochanter on its lateral aspect, into its ventrocephalic .surface a fused muscle mass, representing the p}Tiformis. obturator intemus and gemelli, is inserted.
 +
 +
The adductors magnus, longus, and brevis are small ; separable at their origins, they insert by a common tendon into a ridge immediately above the medial condyle. The psoas iliacus inserts into the lesser condyle: the pectineus is attached immediately distal to it. Xo popliteus nor plantaris muscles are present. The gastrocnemius is a very large mass, and no septal di\'ision of this mass is found which would reveal an underlying soleus. The former muscle arises prmiarily from the dorsal aspect of the tibia, however, a few muscular and fibrous prolongations are found attached dorsally to the distal extremity of the femur mmiediately cephalad to each condyle.
 +
 +
1 1 e tibi . like the rc/Uu-^ of the upper extremity, is abnormally curved, with the convexity directed ventrad, but not to such a
 +
 +
 +
 +
56 EBEN J. CAREY
 +
 +
degree as the radius. The tibial diaphysis is completely ossified, being separated from the epiphyses by intermediate zones of growing cartilage.
 +
 +
There is no fibula.
 +
 +
As a result of the persistent continuity of the patella with the femur, there is no retropatellar extension of the cavity of the kneejoint.
 +
 +
Into the cartilaginous knob, which represents the patella, are inserted a few fibrous bundles from the tendon of the very small rectus f em oris.
 +
 +
Here again emphasis should be placed on the fact that the quadrice])s extensor muscle is represented chiefly bj^ a rudimentary rectus femoris. The vastus internus and externus possess but a few muscular strands, which arise from the mesial and lateral aspects, respectively, of the greatly shortened femur. The vastus intennedius and subcrureus are absent. We have already noted the fact that the adductors, although present, are very small. Here again the normal stimulus to muscular differentiation and development is either absent entirely or minimal. All the nerves are present. The only absent element which we can discover in the thigh is the diaphysis of the femur. Evidently, then, the teratological evidence indicates that the more rapidly developing skeletal (blastemal-chondrous or osseous) axial zone is the nonnal stimulus in nmscular development, and if it is absent entirely or very much reduced, we find also retarded development in the musculature. This fact further explains the failure of separation and rudimentary condition of the patella as correlated to the inhibited development of the quadriceps extensor.
 +
 +
The flexor muscles of the leg form a larger mass than the extensors. This directs the convexity of the tibial bow ventrad. The large gastrocnemius inserts into the cartilaginous calcaneus. The tibialis posticus and the flexor digitorium longus are fused at their origins, but separable at their insertions. The latter muscle also gives rise to the tendon of the flexor hallucis longus, which has no independent belly.
 +
 +
The tibialis anticus is a large muscle and not only has its normal insertion but distributes the tendons normally belonging to
 +
 +
 +
 +
TERATOLOGICAL STUDIES 57
 +
 +
the extensor longus digitoruni. These tendons, however, are small; the latter muscle is absent as well as the three peroriei muscles which nonnally find their origin on the fibula.
 +
 +
In the tarsus the calcaneus, astragalus, cuboid, and navicular are discrete cartilages, but the cuneiform elements form a fused mass.
 +
 +
The metatarsals and phalanges are represented by short, thick cartilage rods. The terminal phalanges have ossification centers at their distal ends. This is comparable to the terminal phalanges of the upper extremity (fig. 8).
 +
 +
The intrinsic muscles of the plantar surface of the foot were not well defined and formed a common muscle mass in which considerable fatty degeneration had taken place.
 +
 +
The condition of club-foot in this monster is readily understood in reference to the extent of development and contraction of the muscles; those belonging to the tibia are well developed, but the fibular muscles are absent except for some of their tendons of insertion which have become amalgamated with the tibial muscles, in consequence the latter group of muscles are practically unopposed in their action. The tibiahs anticus manifests its action by inverting, the strong gastrocnemius by extending the foot, resulting in a talipes equino varus.
 +
 +
In concluding this section I wish again to emphasize the fact brought out in this study, that in the complete absence or rudimentary development of a part of the skeleton, we also find a complete defect or rudimentary development of the related muscles. The converse is also true that an overdevelopment of the skeletal parts is accompanied by a greater degree of development of the related muscles.
 +
 +
B. THE EXTERNAL FORM OF AN ABNORMAL HUMAN EMBRYO OF TWENTY-THREE DAYS
 +
 +
This specimen was given to the writer by Dr. C. J. Nemec, Instructor in Surgery, Creighton University Medical School, January 31, 1917, three hours after miscarriage. The history of the pregnancy is as follows:
 +
 +
 +
 +
58 EBEN J. CAREY
 +
 +
The woman, twenty-one years of age, Bohemian, had been niarried five years. She began menstruating at twelve years of age and invariably' suffered from dvsmenorrhea. Leucorrhea was always evident two to four (lavs before each period. Her time was irregular; it was not unusual for her to miss a periotl completely. She had given birth previously to three sicklv children, the second of which died two months after birth. The last child was born July 31, 1917. During lactation there was the usual condition of amenorrhea. The nursing child was weaned Januarv 6, 1917. Her first coitus since the birth of her last child was on January 7, 1917. On January 25, she noticed a slight flow, the first since her last conception. This condition of metrorrhagia continued until January 31, 1917. At first she thought this was the reappearance of her normal menstruation. But, on the latter date, a hemorrhagic mass was passed, and then I was called on the case. I saw immediately that the uterine decidua had been passed and I had no difficulty in finding the chorionic sac imbedded in this bloody mass. I put the entire mass in 10 per cent formalin, within one hour after it had been expelled, when I returned to my laboratory.
 +
 +
The chorion was found covered with villi 2 mm. in length. The chorionic sac measured 20 x 19 x 10 mm. I opened it and found the abnonnal embryo with its neck extended contained in an amnion with the normal amount of liquor amnii. The chorion was sectioned and was found to be normal, save that it was covered with necrotic syncytium. In this syncytium there was a slight round-cell infiltration. The embryo was unbent in the cervical region obliterating the nape flexure. Especial care was taken to preserve the embryo in the exact position in which it was found. It remained in Zenker's fluid eighteen hours, and excellent preservation was obtained, the surface relief standing out prominently. *
 +
 +
Age. No approximate age in days can be computed from the menstrual history, since the woman was in a condition of amenorrhea at the time cohabitation and fertilization occurred. The former took place January 7, and the miscarriage occurred January .31. Undoubtedly, a living ovum was in the outer third of the Fallopian tube at the time of cohabitation. Allowing twentyfour hours until the time that fertilization occurred, the aborted ovum would be approximately twenty-three days old. The embryo is certainly not over one month old, as the external anatomy agrees very closely wuth the description of embryos between the
 +
 +
 +
 +
TERATOLOGICAL STUDIES
 +
 +
 +
 +
59
 +
 +
 +
 +
 +
Fig. 9 Phocomelus. Skeleton of the lower extremity.
 +
 +
 +
 +
Fig. 10 Twenty-three-day embryo. A pointer is in the amniotic cavity. Fig. 11 Twenty-three-day embryo. Fig. 12 Twentj^-three-day embryo. Fig. 13 Twenty-three-day embryo.
 +
 +
 +
 +
Chorion (above) and deciduae (below)
 +
 +
Ventral view. Right lateral view. Left lateral view.
 +
 +
 +
 +
THE ANATOMICAL RECORD, VOL. 16, XO. 2
 +
 +
 +
 +
60 EBEX J. CAREY
 +
 +
twenty-first and the twonty-thinl days. The embryo stands very close to the embryo a of His's nonnentafeln; embryo 112 of Keibel's collertion. noniiontafohi of Kicbol and Elze. and embryo G 31 of the Anatomical l^iological Institute of Berhn. The specimen is younger tlian the twenty-six-day-old normal embryo described by Mall ( '91 ). In Mall's embryo the eyes are further developed, the liver swelling is more prominent, the branchial arches and clefts are more differentiated, especially the maxillary process of the mandibular arch : the nasal pits are larger, and the limb buds more extended from the body wall. The monster under consideration, however, is older than the 4 mm. embryo described by Bremer, which is estimated approximately at twenty to twenty-one days old. In Bremer's embryo there is no surface marking for the eye and no posterior limbs. The shape, size, and degree of development are midway between Bremer's 4nun. embryo, aged twenty-one days, and ^Mall's 7-mm. napebreech embryo, twenty-six days old, and twenty-three days in all probabihty is its age. The measurements of the embryo before fixation are as follows:
 +
 +
m m .
 +
 +
Height of yolk-sac when it projects fror.. ur. bilicus 0.9
 +
 +
Maxin al height of yolk-sac 2.5
 +
 +
Length of yolk-sac 4.0
 +
 +
Length of posterior portion of body, measured from the point of
 +
 +
emergence of yolk-sac 0.9
 +
 +
From fore-brain to tip of coccyx following curvature 13.0
 +
 +
Straight line from l)oundary between neck and thoracic region.'? to _
 +
 +
twelfth thoracic segment (nape-breech) 40.0 - . A
 +
 +
Greater length in a straight line (crown-breech) 6.0
 +
 +
From vertex to behind the m.andibular process 0.9
 +
 +
From vertex to behind the heart 3.3
 +
 +
External form
 +
 +
It is readily ai:)parent from the photographs that the cervical flexure of the embryo has been abnoniially unbent. This is further seen in the sharp groove on the nape separating the neck from the back. There is a very marked degree of curvature noticed in the dorsal, lumbar, and coccygeal segments. If the neck
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TERATOLOGICAL STUDIES 61
 +
 +
and head had not unbent, the embryo would fomi ahnost a complete cncle; the tail would he m close proximity to the head, if not actually touching it. The body is bent anteriorly and at the same tune sphally twisted about its axis so that the head is turned shghtly to the right and the pelvic end to the left.
 +
 +
The first, second, third, and fourth arches are clearly defined, especially the nodular ventral end of the mandibular arch ffig. 13). The maxillary processes are perceptible on both sides, not to the extent, howe^'er. found in ^vlall's twenty-six-day old embryo. The second bar is not so bulbous as the first nor the third so prominent as the second. The region of the sinus praecer^-icahs is distinct, but not so depressed as in flail's embryo. The fourth arches are barely perceptible on both sides. They lie deep m the groove of the sinus praecervicalis and are covered b}' the third arches. The clefts begm to show a shght irregularity. Above the branchial region (^approximateh' above the second visceral groove) on both sides there is a smaU oval depression inunediateh' above the otic vesicle measuring 0.25 nmi. in diameter.
 +
 +
The head shows the outline of the bram and the marked elevation over the region of the Gasserian ganghon. The shape of the cerebral hemisphere, the interbrain. midbrain, and afterbrain are plainly recognizable, and the boundaries of the fourth ventricle are sharply defined. From the dorsolateral aspect I was able to define the neuromeres in the lateral waUs of the fourth ventricle: these appeared as bilaterally s}inmetrical transverse folds. The optic vesicles are circular in fonn on each side and measure 0.3 mm. in diameter. The nasal pits are oval and shallow, but not as large as [Mali found them in his embryo. The mouth is a large shallow pentagonal depression bounded above b}' the nasofrontal process: below and lateral by the nodular mandibular processes on both sides: and lateral, the mmute elevations craniad to the mandibular processes, the incipient maxillary processes. It is readily apparent that a line dra\\Ti vertically through the ventral ends of the four visceral arches would be approximately straight and would cut the forebrain some distance in front of the optic ^•esicles. The marked prominence of the forebrain noticed in the phocomehc monster we see is a very characteristic human feature in earh' embrj'os.
 +
 +
 +
 +
(>2
 +
 +
 +
 +
EBEN J. CAREY
 +
 +
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Fin. 14 ('raniorrharhischisi.s. \'('iitral view.
 +
 +
Fig. 15 Craniorrhachischisis. Hifiht lateral view.
 +
 +
Fig. 16 Craniorrhachischisis. Skiaura|)h. Dorsal view.
 +
 +
Fig. 17 Craniorrhachischisis. Skiagraph. Lateral view.
 +
 +
 +
 +
TERATOLOGICAL STUDIES 63
 +
 +
The anlage of the heart projected ff-om the ventral surface of the body as a large nodular swelling: its prolongation on the right side extends forward as the aortic bulb. If the neck was normally bent, the relief of the aortic bulb would extend to the edge of the mandibular arch. The atrial portion of the heart is seen as a protuberance on the lateral wall through the thin wall of the pericardial canity. The atrial swelling is more marked on the left side and the swelling of the aortic bulb on the right. Caudal to the heart the \4teUine vesicle projected from the umbiUcus; this vesicle was shrunken and pear-shaped.
 +
 +
The hver swelling is poorh' developed and the tail is curved to the left between the cardiac swelling and the body stalk.
 +
 +
The marked coccygeal and pehde cur\^e is seen from the left as a hook-like process. The tail is conspicuous as is usual in human embryos of this age.
 +
 +
In the posterior region of the trunk four parallel ridges are present; two belong to the axial zones, the medullary and somitic ridges; two belong to the parietal zone, the Wolffian and marginal ridges. There are thirty somites present.
 +
 +
The upper extremities are simph' oval moimds; thej^ have not become plate-hke as yet. The lower extremities are but ill-defined ridges.
 +
 +
The umbihcal cord is large and lies on the left side; a similar condition is found in the embryos described by Mall, Waldeyer, and Janosik, a departure from the usual right-sided position of the cord in human embryos.
 +
 +
C. THE ANOMALIES OF AX AXEN'CEPHALIC MONSTER— COMPLETE CRANIORRHACHLSCHISLS
 +
 +
The specimen represented in figures 14, 15, 16, and 17, was given to the ^Titer by Dr. J. S. Foote, Professor of Pathology Creighton University ^Medical School, in 1914. Xo clinical data were obtainable. The specimen, approximately eight months, old, weighed 1.500 grams, and was 20 cm. in length from the breech to base of skull at its dorsal aspect.
 +
 +
The interesting fact in regard to the anencephalic monsters is that they are usuallv of the female sex : the monster under con
 +
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 +
64 EBEX J. CAREY
 +
 +
sideration was a female. The marked abnormalities are the absence of the brain, spinal cord usually, and lack of development of the bones of the vault of the cranimn and of the lamina of the vertebral colmim.
 +
 +
Surface anatomy
 +
 +
Ventral aspect (fig. 14.) : The anns are in an unnatural positionThey were forcibly dra^^-n lateral to the lower limbs in order to procure a clearer view of the face and ventral regions. The striking feature is the attitude of the head. It is sunk between the shoulders and extended. Owing to the absence of the cranial vault, the face is very prominent. The tongue protrudes from the mouth, the eyes project markedly from their sockets and look upward. This is due to the fact that the forehead is abnonnally sloped backward, the supraorbital plates are rudimentary and are necessarily tilted in the same direction as the forehead. The nose is broad and flat and the mouth is partly open.
 +
 +
The broad shoulders and the general plump appearance of the trunk and the overdeveloped upper extremities present a curious contrast to the defonned head. The excessive development of the shoulders and upper limbs usually gives rise to serious dystocia. The abnormal shape of such a head generally leads to face presentation. Owing to the exposed condition of the base of the brain, there is frequently a marked increase in the amniotic fluid.
 +
 +
There is a partial development of the frontal, parietal and occipital bones towards the narrow base of the skull. These rudiments slant mesiad and are not prominent. The brain is represented by a conglomerate mass of membranes, blood-vessels, and connective tissue. There is absolutely no trace of nervous tissue of the cerebrospinal axis. These i-udiments of the central nervous system, just enumerated, entitle this monster to be classed as a pseudoencephalus, according to Geoffroy Saint-Hilane, who reserves the term anencephalus for those monsters in which absolutely no membranous rudiment of any kind is present.
 +
 +
 +
 +
TERATOLOGICAL STUDIES 65
 +
 +
Xo neck is definable. The umbilical cord possessed one vein, but only a single artery, a fact noted by Gillaspie and Henston ('17) in the anencephalus described by them.
 +
 +
Right lateral aspect (fig. 15). The partial development of the frontal and parietal bones and their marked slope inward is well sho"\;\Ti. The exposed membranes, connective tissue and bloodvessels are seen as a protuberance on the dorsocephalic aspect of the head. The well-developed and plump appearance of the trunk and upper lunbs are seen in this view, and forms a decided contrast to the abnormal head. The slit on the lateral aspect of the right thigh was made in taking out the femur.
 +
 +
Dorsal aspect (fig. 16). The condition of craniorrhachischisis is apparent. The lack of development of the calvarium. consisting of the squamous part of the occipital, parietal bones and frontal bone, is well sho\Mi. The membrane and connective tissue over the dorsal aspect of the base of the skull and floor of the vertebral canal, which is wide open, were left intact. The edges of the peduncles of the vertebra form a contmuous ridge on both sides of the wideopen vertebral canal. These are seen as fight linear ridge? on both sides of the dark groove. The broad welldeveloped shoulders stand out prominently.
 +
 +
Left lateral aspect (fig. 17). The more marked buigmg of the left eye is better seen in this view. The lack of development of the left supraorbital ridges together with its acute slope inward causes this eye to look upward and to protrude more than the right eye. The eversion of the right foot and inversion of the left are manifest. The club-foot condition of the former is of the tafipes calcaneus variety: of the latter, of the talipes varus variety.
 +
 +
Internal anatomy
 +
 +
The topogi'aphical relations within the thorax were nonnal. The lungs and th\Tnus showed no marked abnomiafities. The heart showed a high degree of defect in its septa both in the atrium and in the ventricle. The septum primum and septmn secundum of the auricular partition were nidunentary, lea\-ing an abnormally enlarged foramen ovale. The ventricular septum
 +
 +
 +
 +
66 EBEN J. CAREY
 +
 +
was represented Idv mere ridges. The auricular-ventricular valves were quite inadequate and did not function as valves at all. There was evidently marked cardiac incompetency.
 +
 +
In the abdomen the intestines, liver, pancreas, spleen, kidneys, and suprarenals were normal. It has previously been pointed out that there was but one umbiUcal artery. Upon dissection this proved to belong to the left side. A persistence of but one umbiUcal artery belonging to the right side was pictured and described by Gillaspie and Henston ('17). In their specimen the uterus was displaced to the left, owing to the fact that the aorta was directly continuous in the median hne with the right h\'pogastric artery. In my specmien a similar arterial condition existed in the pelvis with the difference that the persistent umbiUcal artery belonged to the left side which in turn caused a displacement of the uteiois to the right instead of to the left.
 +
 +
Although the muscular system was dissected and studied, no detailed report will be made here except to state that a stemalis muscle was found on both sides in this specimen, but not in the second monster. The arteries to the limbs were nonnal as well as the peripheral nervous system. The condition of the skeleton is well depicted in the skiagraph, figures 16 and 17. Note especially absence of the spinal lamina as well as the cranial vault in the dorsal aspect (fig. 16). The base of the skull was accessible to the examining finger. The sella turcica and the anterior and posterior clinoid processes were easily palpated.
 +
 +
The styloid process of the right side is precociously ossified and throws a dark shadow in the skiagraph.
 +
 +
In consequence of the ill-development of the laminae of the cervical vertebrae, there is a lordosis in this region (lateral aspect skiagraph). It is also definitely seen that there is a compensatory kyphosis of the upper thoracic vertebrae, extending the head and allowing it to sink between the shoulders, and giving the fetus an attitude characteristic of many forms of deficient head and spine development. There is also present a marked kyphosis in the lumbar region beginning at the twelfth thoracic vertebra and extending to the first sacral vertebra.
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 +
TERATOLOGICAL STUDIES 67
 +
 +
The position of the mandibula and the protrusion of the tongue, which are really an exaggeration of the first act of deglutition, are to be attributed to the unperfect development of the temporal muscles, allowing the depressors to predominate. Of the temporal muscles only the fascicuh arising from the lower part of the fossa are present ; these insert upon the coronoid process. They thus are largely representative of the posterior part of the muscle, which is active mainly in retracting the jaw. The large anterior portion, which elevates the jaw, is absent.
 +
 +
All the mandibular depressors are present, with only the small masseter and the internal pterygoid to oppose their action. Accordingly, the typical open mouth of anencephalic monsters is correlated to the defect in the cranial vault and the associated loss of the anterior portion of the temporal muscle.
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D. A SECOND ANENCEPHALUS :\IOXSTER— COMPLETE CRAXIORRHACHISCHISIS
 +
 +
This specimen was given to the ^mter in December, 1917, by Dr. T. J. Dwyer, Associate Professor of Surgery, Creighton University Medical School. It was prematurely bom at eight mqnths and at first presented by the face. However, because of the overdeveloped shoulder, even more marked than on the forgoing specimen, an obstruction was presented to the descent of the child which called for podalic version. There was a marked condition of hydramnios. Before birth, at six months, the child had been predicted by Dr. Dwyer to be an anencephalos. This condition was suggested by the hydramnios and the exaggerated intensity of the fetal movements which were also irregular and spasmodic in character.
 +
 +
The monster was a female. The condition of craniorrhachischisis was more extensive than in the fonner specunen. The spina bifida extended through the coc€jtc. Absolutely no remnants of the calvarium were present. No membranous rudunents were found and only a sUght amount of connective tissue covered the base of the skull. Both eyes bulged even more prominently than the left eye of the first specimen because of the greater slant and arrest of development of the supraorbital ridges and plate.
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68 EBEN J. CAREY
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Two arteries and one vein were found in the uni])ilical cord. No stemalis muscle was found. Outside of these differences the description' of the first specimen holds for the monster under consideration; but the abnormalities of the heart are if anything more extensive.
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 +
Ahlfield ('80) assigns as the direct and immediate cause of anencephalic monsters, hydrocephalus. If the serum accumulates early within the ventricles, the bram and its covering are ruptured at about the fourth week of embryonic hfe, they atrophy and disappear and the result is anencephalous. The accumulation of serum may make it impossible for the bony case of the brain to enclose the cranial cavity, causing thus varying defects of the skull through which the membranes and their contents protrude. If the serous effusion affects the spinal region as well as the cranial cavity before closure of the neural tube, which is thus prevented, there is an associated spina bifida resulting therefore in the condition of craniorrhachischisis.
 +
 +
The primary cause of hydrocephalus can only be surmised. Many have made a vague reference to the already overworked amniotic bands. It is interesting to note that Morgan has experimentally produced spina bifida in the tadpole of frogs by subjecting the eggs to a 0.6 per cent solution of common salt. This retards development and results in posterior spina bifida. In regard to the underlying cause of anencephalic monsters with spina bifida. Mall ('10) concludes: It is no longer'necessary for us to seek mechanical obstructions which may compress the umbihcal cord, such as amniotic bands, for it is now clear that the impairment of nutrition which naturally follows faulty implantation or the various poisons which may be in a diseased uterus, can do the whole mischief."
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TERATOLOGICAL STUDIES 69
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LITERATURE CITED
 +
 +
Ahlfeld, a. 1880-82 Die Missbildungen des Menschen. Parts I and II.
 +
 +
Leipzig. Bellard, Eugene G. 1882 Contribution a I'etude des monstres celosomiens.
 +
 +
Lille. Birmingham, A. 1889 On the nerve supply of the sternalis in an anencephalous
 +
 +
foetus. Trans. Royal Acad, of Med. of Ireland, vol. 7, Dublin. Bremer, J. 1906 Description of a 4-mm. human embryo. Am. Jour. Anat.,
 +
 +
vol. 5. Boemer, Emil C. 1887 Anatomische Untersuchung eines Kindes mit Phoco melie. Marburg. Broca, p. 1882 Note sur les monstres ectromelus. Rev. d'Anthrop., T. 10,
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Paris. Charon, E. 1880 Monstre ectromelien, se rapprochant du phocomelie. Journ.
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de med., chir. et pharmacal, T. IXX. Bruxelles.
 +
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Monstre ectromelien, se rapprochant du phocomelie. Presse med.
 +
 +
Beige, T. 23, Bruelles. Davis, E. W. 1885 A child born without arms. Med. Herald, Louisville,
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 +
vol. 4. GiLLASPiE AND Henston. 1917 Study of monster with craniorrachischisis. '
 +
 +
Anat. Rec, vol. 13, no. 5, pp. 289-295. Hallet, E. 1847 Monsters with eventration. Edinb. Med. and Surg. Journal,
 +
 +
vol. 68. Herve, G. 1886 Sur un cas d' hemimelle. Bull. Soc. d' Anthrop. de Paris,
 +
 +
T. 9. Hirst, B. C. 1889 A phocomelie monster. Univ. Med. Mag., Phila., vol. 2,
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p. 151. Hughes, A. W. 1887 The central nervous system and axial skeleton in anencephalous monsters. Lancet, vol. 2, p. 1212, London. Jackson, C. M. 1909 On the prenatal growth of the human body and the
 +
 +
relative growth of the various organs and parts. Am. Jour. Anat.,
 +
 +
vol. 9. Laulaigne, J. 1883 Contribution k I'etude de I'anencephalie; diagno.stique
 +
 +
pendant la grosse. ' Macdougall, J. 1878 Foetal monstrosity (phocomelus). Trans. Edinb. Obstet.
 +
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Soc, vol. 4. Mall, F. P. 1891 A human embryo twenty-six days old. Journ. Morph.,
 +
 +
vol. 5. Mayer, E. 1882. Acranial monsters with report of a case. Amer. Journ. Med.
 +
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Sci. Phil., N. S., 83. Mills, T. W. 1880 Case of congenital ectopia of abdominal organs. Canada
 +
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Journ. Med. Sci., vol. 5, Toronto. P.\TERSON, A. 1878 Notes of a case of anencephalous foetus born co-twin with
 +
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a healthy- child. Trans. Edinb. Obstet. Soc, vol. 4. RiBBERT, H. 1883 Beitrag zur Entstehung der Anencephalie. Arch. f. path.
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Anat., Berlin, Bd. 93. S 396-400.
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70 EBEN J. CAREY
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Sentex, L. 1SS6-87 Phocomelie accompagneed'entrodactylie. Journ. de Med.
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de Bordeaux, T. 16. Shephehd, F. J. 1884 The musculus sternalis and its occurrence in (human)
 +
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anencephalous monsters. Journ. of Anat. and Physiol., London,
 +
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vol. 19, pp. 311-319.
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1885 On the musculus sternalis occurring in anencephalous monsters.
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Trans. Acad. Med. of Ireland, vol. 3, pp. 439-446. Dublin. Westbrook, B. F. 1879-80 Microcephalus. Proceedings of Med. Soc. County
 +
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of Kings, vol. 4. p. 275. Brooklyn. V. Leonowa, O. 1890 Ein Fall von Anencephalus. Uber den feinen Bau des
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Rijckenmarkes eines Anencephalus. Arch, f . Anat. und Entwicklungs geschichte. Bd. 10, S. 403-422.
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70
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Resumido par la autora, ^Maiy Drusilla Flather.
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La irrigacion sanguinea de las areas de Langerhans; estudio comparativo del pancreas de los vertebrados.
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El presente trabajo es el primero de una serie de estudios comparativos sobre la irrigacion sanguinea especializada en las areas de Langerhans. La introduccion contiene un corto resunien de los trabajos ya verificados en el campo general sobre el origen y funcion de las areas insulares y su estructura histo16gica. La autora hace un estudio comparativo de la disposicion de las celulas y vasos sanguineos en las areas insulares del aligator, opossum, caballo, racoon (Procyon lotor), badger (Taxidea taxus), skunk (Alephitis putida), conejo y conejillo de Lidias. Los resultados obtenidos llevan a la conclusion de que, mientras que las areas vasculares son en extremo variables, incluso en el mismo individuo, hay ciertos rasgos distintivos — forma, tamano, red sinusoidea, etc., — que caracterizan a los islotes de las diferentes especies de vertebrados. El trabajo esta ilustrado con ocho figuras de los ejemplares examinados, dibujadas con la camara clara. La tecnica empleada en la obtencion de las preparaciones se describe en el texto.
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Translation by Jos6 F. Nonidez Columbia Univers ty
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AUTHOR S ABSTRACT OF THIS PAPER ISSUED BY THE BIBLIOGRAPHIC SERVICE, MARCH 17
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THE BLOOD SUPPLY OF THE AREAS OF LANGERHANS, A C0:MPARATIVE study from the PANCREAS OF VERTEBRATES. (PRELIMINARY PAPER.)
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MARY DRUSILLA FLATHER
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Bryn Mawr CQllege
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EIGHT FIGURES
 +
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INTRODUCTION
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Since 1895, when the islets of Langerhans were declared by L. A. Shaeffer to be endocrinous glands, secreting a substance capable of modifying the metabolism of carbohydrates in the tissues, the study of these organs has been provocative of deep interest and much controversy. It is my purpose in this paper to present a purely comparative study of the specialized blood supply in the islets. Therefore, in my consideration of the work already accomplished in the general field, I shall mention only those facts which are necessary for an adequate comprehension of my problem. A detailed summary of the literature up to 1906 is given by Laguesse in La Revue Generale d'Histologie, vol. 2, 1906-1908. Two important contributions since then are the papers of Lydia M. Dewitt in The Journal of Experimental ]\Iedicine, 1906, vol. 8, and of R. R. Bensley in The American Journal of Anatomj^, 1911-1912, vol. 12.
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It is generally conceded that islets are groups of internally secreting glands embedded in the pancreatic tissue of all species of vertebrates. Their origin is still a matter of controversy, although the careful work of Dewitt and of Bensley seems to prove conclusively that the islets and acini arise from common anlagen, later becoming differentiated and incapable of transformation one into the other. The cells, varying in form and structure, are always arranged in cords or masses separated by
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71
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72 MARY DRUSILLA FLATHER
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large ana>t()in()sing blood-vessels. The nature of this vascular network is analogous to that found in other endocrinous glands, especially the thyroid and sui^rarenals. According to Jordan and Ferguson, certain arterial branches enter the islets and form a plexus of large capillaries from which the blood is drained through the venous system. Dewitt, however, claims that the sinusoids communicate intimately with an interacinar capillary plexus and with larger \essels of venous origin onl}^ basing her theory upon lier inability to find near the islets any of the characteristic arterial endothelium.
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The islets vary in size and shape according to their vascular content and according to whether they are singular or compound. Harris and Gow find three distinct types of islets — those which are lym]:)hoid in appearance with many small, deeply stained nuclei in a syncytial mass of tissue; those having distinct cell outlines, and those consisting of compound cell groups divided into smaller areas by strands of connective tissue. It is probable that the first two types represent physiological differentiation only. Usually the cells toward the periphery of the islet are massed, while those in the center are arranged in irregular cords one or two cells in depth resting directlj' on the walls of the capillaries. As a rule, a connective-tissue sheath surrounds the islet, sometimes penetrating within, and frequently failing to separate the acinous and islet cells completely. It is often difficult to distinguish the islet from the peri-insular zone, but in general the islet cells may be recognized by their polymorphism, their slight colorability, their small size, and the large chromatin content of their nuclei. In addition to the rich blood supply there is also in the islet a plexus of nerve fibers, which was shown by Pensa to pass along the blood-vessels and in between the cells.
 +
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THCHXIQUE
 +
 +
In my own investigations on the histology of the islet cells I am much indebted to Dr. Frederick M. Allen for supplying me with the greater part of the material which I have used. The specimens of fdligator, opossum, horse, coon, badger, and skunk
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BLOOD SUPPLY AREAS OF LAXGERHANS 73
 +
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pancreas which I obtained from him had been fixed in either chrome subhmate or Zenker's solution and embedded in paraffin. From these blocks I cut sections 3 to 5 m thick, and stained them all in ]\Iallory's connective-tissue stain before mounting them for observation. Fresh material was taken from a guinea-pig and a rabbit. Following Bensley's directions, I employed all four of his methods of fixation, and used the neutral gentian stain. The most successful results were from the Zenker bichromate sublimate fixation. Both neutral gentian and Alallory's connective-tissue stain proved excellent in the differentiation of the islets and the surrounding tissue. The drawings were made with a camera lucida, using a Zeiss oil-inmiersion lens and no. 4 ocular, resulting in a total magnification of 1250.
 +
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THE BLOOD SUPPLY OF THE AREAS OF LAXGERHANS
 +
 +
A cursory glance at the accompanying figures shows how varied is the arrangement of the vascular areas in the islets of Langerhans. To a certain extent there may be variation even in the isiets from the same individual, but I shall endeavor to show that there are certain distinctive features which characterize islets in the different species of vertebrates.
 +
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In the alUgator, figoire 1, the islets are noticeably large, compound, and syncytial in appearance, with a very appreciable granular content due to great physiological activity. This latter feature msiy be due merely" to the youth of the specimen. With the physiological vascular injection produced by congestion it is easy to see how the distended blood-vessels surround the area, rarely penetrating within it, except in the connective-tissue sheaths, and forming ahnost a complete barrier between the islet and acinous cells. There is no differentiation between the peripheral cells and those of the interior of the islet, and no indication of a capillary network. In ten islets from the same individual there was no appreciable variation except in size. Many of the islets were larger than the one represented here.
 +
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The islet from the opossum, figiu'e 2, presents a quite different appearence with distinct cell divisions, a sinusoidal arrangement
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THE ANATOMICAL RECORD, VOL. 16, N'O. 2
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74 MARY DHUSILLA FLATHER
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of blood-vessels in the interior of the area, no encircling; vessels, and no definite capsule or sheath to se]xirate the islet from the acinous cells. A pecuUarity of the cell arrangement not found in any other pancreas observed is the radial grou])ing around capillaries, which is most suggestive of the radial form of acinous cells about their Imnina. These essential features were found in ten islets from the same pancreas.
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The islet from the horse, figure 3, is definitely ovoid in shape, and is surrountled by a frame of blood-vessels and connective tissue, which in places penetrate within the area. The cells are clearly outlined, but show no differentiation between the central and jDcripheral grouping in any of the ten islets studied.
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The distinctive feature of the raccoon islet, figure 4, is the compound form and lobular appearance. The smaller masses are separated by a network of blood-vessels and connective tissue which also lies between the acinous cells and the large islet area. Another characteristic is the extensive penetration of the lobules by the capillaries. The cell outlines are fairly distinct, but again there is no different iation, even where the blood-vessels have invaded the central mass. There was no variation worthy of note in ten islets from the same pancreas.
 +
 +
As might be ex])ected from their close relationship, the skunk and badger, figures 5 and 6, have islets with many shnilarities of structure. In both, the blood-vessels only partially separate the acinous from the islet cells. There is a definite sinusoidal netwoi-k running through the central mass. This makes it possible for neai'ly every cell to come in contact with the capillaries, a feature which should greatly facilitate the circulation of the secretion. Figure 6 shows a large accumulation of interlobular connect i\e tissue at one side where the area of the islet reaches the periphery of the lobule. From a study of ten islets from
 +
 +
Kid- 1 Island of L:inp;prh:uis frorn youiifi alligator. Aq. chrome subliiuattMallory. X 417.
 +
 +
Fig. "2 Island of Laiigerhans from opo.s.suiii. Zenk(MMallory. X 417. Fig. .3 Island of Langorhans from hor.so. Aq. choniosublimate Mallory. X 417. Fig. 4 Island of Langcrhans from racoon. Zenker Mallory. X 417. a. acinous cells; h, islet cells; r, blood vessels; (/. connective tissue.
 +
 +
 +
 +
BLOOD SUPPLY AREAS OF LAXGERHAXS
 +
 +
 +
 +
75
 +
 +
 +
 +
 +
MARY DRUSILLA FLATHER
 +
 +
 +
 +
 +
^ a
 +
 +
 +
 +
 +
 +
BLOOD SUPPLY AREAS OF LANGERHANS 77
 +
 +
each individual it was concluded that the islet areas were smaller in the skunk than in the badger pancreas.
 +
 +
In the islet of the rabbit, figure 7, the line of demarcation between the islet and acinous cells is difficult to define because the former frequently extend into the acinous area and there is no circle of blood-vessels or connective-tissue sheath to mark the division. The blood supply is sinusoidal in nature. In this fonn there is a slight indication of cord-Uke cell grouping and a massing of cells with larger nuclei toward the periphery. Unlike Dewitt, I found in the ten islets examined no radial arrangement sunilar to that which was observed in the opossmn.
 +
 +
The guinea-pig islet, figure 8, shows a fairly regular contour, a connective-tissue sheath separating the islet and acinous areas, and an irregular network of insular cells frequently but one cell in depth surrounding the large and abundant sinusoids. After careful observation of islets from two individuals and with due allowance for faulty fixation, I decided that these islet areas were the most sponge-like of any that I have examined.
 +
 +
From the islets which I have described I feel that there is an arrangement of the cells and blood-vessels which may be regarded as characteristic of a species. Within certain Imiits there may be variation in size and in abundance of capillaries with a consequent rearrangement of the islet cells. However, I beUeve that the special features can be proved pecuhar to the species. I realize that the proof is inadeciuate as yet owing to the fact that with one exception I have studied islets from only one individual of a species. It is my intention to continue the investigation with many more species and more individuals of the species. I am greatly indebted to Dr. David H. Tennent for his helpful supervision of the work.
 +
 +
Fig. .5 Island of Langerhans from skunk. Chrome sublimate Mallorv. X 417.
 +
 +
Fig. 6 Island of Langerhans from badger. Chrome sublimate Mallorv. X 417.
 +
 +
Fig. 7 Island of Langerhans from rabbit. Zenker neutral gentian. X 417.
 +
 +
Fig. 8 Island of Langerhans from guinea-pig. Zenker neutral gentian. X 417.
 +
 +
a, acinous cells; b, islet cells; c, blood vessels; d, interlobular connective tissue.
 +
 +
 +
 +
Resuniido por la autora, Inez Whipple Wilder.
 +
 +
Una anomalia de la circulacion de la porta en el gato.
 +
 +
En un gato macho de gran tamano y aproxiniadamente de un aiio de edad, un espacioso canal sanguineo colateral, formado por la anastomosis de los tributarios de la porta con la vena frenica izquierda, hacia posible el paso directo de la sangre desde dichos tributarios a la vena i)ostcava, evitando de este modo el trayecto normal a traves del higado, si bien este tra5^ecto estaba abierto. Con esta anomalia estaban asociados: un aumento de tamano de los riiiones y una disposicion irritable en extremo, por parte del animal.
 +
 +
Translation by Jos6 F. Nonidez Columbia University
 +
 +
 +
 +
AUTHOR S ABSTRACT OF THIS PAPER ISSUED BY THE BlBLIOGR.U>HIC SERVICE, MARCH 17
 +
 +
 +
 +
AN ANO:\IALY IN THE PORTAL CIRCULATION OF
 +
 +
THE CAT
 +
 +
INEZ WHIPPLE WILDER
 +
 +
Department of Zoology, Smith College, Northam-pton, Massachusetts
 +
 +
FOUR FIGURES
 +
 +
While injecting the circulatory system of a cat recently, I noticed that the injection of the systemic veins through the right femoral resulted in nearly filling the hepatic portal tributaries, so that when I came to make the usual yellow injection of the portal system through one of the mesenteric veins, I found these already filled with the blue venous injection mass.
 +
 +
L'pon dissecting this specimen I found that the hepatic portal vein was small, while there was a very large collateral connection between the hepatic portal system and the pqstcava. A comparison of this aberrant condition (figs. 1 and 2) with the normal condition (figs. 3 and 4) makes it evident that this collateral is formed by the anastomosis of the coronary veins of the stomach with the left phrenic vein, so that the collateral vein thus formed extends along the lesser curvature of the stomach, and enters the postcava at the level of the diaphragm. A voluminous anastomosis of the gastrosplenic vein with this collateral furnishes a very direct channel into the postcava from the whole system of mesenteric tributaries, as well as from the gastrosplenic vein itself. Near the junction of the collateral with the main portal vein, the collateral is joined by the combined pancreaticoduodenal and gastro-epiploic veins, thus completing the direct connection of all of the portal tributaries with the postcava through the coronary collateral. The blue injection mass had thus backed into the portal system directly from the postcava and had entered not only all of the portal tributaries, but the portal vein itself and all of its branches to the various lobes of the liver.
 +
 +
79
 +
 +
 +
 +
80
 +
 +
 +
 +
INEZ WHIPPLE WILDER
 +
 +
 +
 +
 +
FiK- 1 N'ontral view of dissection of anomalous cat showing tiic anastomosis of the coronary and gastrosplenic veins with the k»ft phrenic, resulting in the for.mation of a direct collateral drainage from the portal system into the postcava. The diaphragm is represented as slit from the midventral line to the postcava, the liver is lifted, and both liver and diaphragm are drawn anteriorly to display the relationships of the blood-vessels.
 +
 +
 +
 +
PORTAL CIRCULATION OF THE CAT
 +
 +
 +
 +
81
 +
 +
 +
 +
It seems probable from the large size of the collateral vein as compared with the unusually small size of the main portal vein, that a large proportion of the blood had habitually escaped its normal course through the liver capillaries, and had entered directly into the main circulation, carrjdng with it continually an excess of nutritive material and unconverted nitrogenous wastes.
 +
 +
 +
 +
 +
Fig. 2 Details of the connections of the portal system with the collateralchannel in the anomalous individual, shown by lifting the pyloric end of the stomach and carrying it anteriorh' and to the left.
 +
 +
 +
 +
It could scarcely be miagined that such a condition would not be accompanied by other abnormalities if not by actual pathological conditions. There was, however, nothing unusual in the appearance of the freshly killed specunen, which was a rather large male, well developed, but not unusually fat. Unfortu
 +
 +
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S2
 +
 +
 +
 +
INEZ WHIPPLE WILDER
 +
 +
 +
 +
nately, the abnormal condition of the circulatory system was not discovered in time to make any liistological study of liver or kidneys. In fact, no examination of these organs was made while the specimen was fresh, and as the preserving fluid had not well penetrated the anterior abdominal organs, it was impossible to
 +
 +
 +
 +
 +
Fig. 3 Ventral view of dissection of normal cat seen from a point of view similar to that of figure 1.
 +
 +
 +
 +
determine whether the somewhat shrunken and flabby appearance of the liver was due to faulty preservation or was the condition of the organ during life.
 +
 +
On the other hand, as might be expected from the inevitable increase in the amount of work devolving upon the kidneys as a
 +
 +
 +
 +
PORTAL CIRCULATION OF THE CAT
 +
 +
 +
 +
83
 +
 +
 +
 +
result of the interference in the normal functions of the liver, the kidneys were undoubtedl}^ enlarged. This fact is shown by the accompanying tabulation of measurements of kidney and total body lengths made upon the abnormal individual and upon ten apparently normal individuals taken at random from specimens
 +
 +
 +
 +
Po.«t>-e<>-tl't.o.
 +
 +
 +
 +
 +
Fig. -i Details of relationships of portal tributaries in the normal individual seen from a point of view similar to that of the anomalous individual shown in figure 2.
 +
 +
in the laboratory similarly injected and preserved by the same method as the abnormal one. The total length was measured from the tip of the nose to the posterior end of the ischiadic sjanph^'sis with the specimen lying upon its back upon the table, and
 +
 +
 +
 +
84
 +
 +
 +
 +
INEZ WHIPPLE WILDER
 +
 +
 +
 +
the head held back to approximately the samt degree. In the very nature of the case, however, these total-length measurement.^j have only an approximate degree of accuracy.
 +
 +
 +
 +
T.\BUL.\TIOX OF ME.\.SIRE.MENTS
 +
 +
 +
 +
TOTAL LE.VGTH
 +
 +
 +
 +
AVERAGE
 +
 +
LE.N'GTH OF
 +
 +
KIDNEYS
 +
 +
 +
 +
PROPORTIONATE LENGTH OF KIDNEYS
 +
 +
 +
 +
Normal individuals
 +
 +
 +
 +
Female
 +
 +
Male
 +
 +
 +
mm.
 +
 +
430 490 470 415 475 480 450
 +
 +
430
 +
 +
480 450
 +
 +
 +
mm. 31.5
 +
 +
43.0 40.0 30.0 38.5 37.0 43.0
 +
 +
37.5 49.0 36.0
 +
 +
 +
per cent
 +
 +
7.3
 +
 +
8.8 8.5 7.2 8.1 7.7 9.6
 +
 +
8.7
 +
 +
10.2
 +
 +
8.0
 +
 +
 +
\
 +
 +
 +
Female
 +
 +
 +
 +
 +
Female
 +
 +
 +
 +
 +
Female
 +
 +
Female
 +
 +
 +
 +
 +
Female
 +
 +
 +
Gravid (ad
 +
 +
Female
 +
 +
 +
vanced)
 +
 +
 +
Male
 +
 +
 +
 +
 +
Female
 +
 +
 +
Gravid (ad
 +
 +
 +
 +
vanced)
 +
 +
 +
Average
 +
 +
 +
456
 +
 +
 +
38.5
 +
 +
 +
8.43
 +
 +
 +
 +
 +
 +
Abnormal individual
 +
 +
 +
 +
Male.
 +
 +
 +
 +
500
 +
 +
 +
 +
60.0
 +
 +
 +
 +
12.0
 +
 +
 +
 +
It will be noted that although there is a considerable range of variation in both the actual and the proportionate length of kidnej^s of the normal individuals measured, in none of these does either the actual or the proportionate length equal that of the abnormal individual.
 +
 +
Inquiries were made to determine, if possible, whether there had been anything abnormal in the behavior of the cat or any indications in its history of a pathological condition. It was learned that the cat was about a year old and had always been peculiarly active and irritable. Even as a kitten it had never tolerated petting, and, to quote the informant, a member of the family of the donor, "it was the strangest acting cat" he had ever seen. It was at first denied, however, that the cat had ever been patho
 +
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PORTAL CmCULATIOX OF THE CAT 85
 +
 +
logical but the admission was finally made that it had had a 'fit' a short time before it had been donated to the laboratory, and that this fact, together with the increasing excitability of the animal, had led to its being donated to the laboratory. This account points rather significantly to an inability of the kidneys to cope fully with the extra work devolving upon them as a result of the interference with the full function of the liver.
 +
 +
This case would seem also to have some embrj'ological significance, since, as pointed out b}^ Huntington and AlcClure C07) in referring to conclusions based upon the dissection of 605 cats by Darrach TOT) although the average individual assumes the venous and l^^llphatic tj'pe considered normal for the species, '" by the well-known process of selection and continued development of certain embryonic pathways while others undergo degeneration, it has been found possible to "interpret all of the observed adult variants as examples of atypical persistence of early channels normally destined to disappear in the course of further development, but capable, by continued and unusual growth, of affording all of the variations of the adult venous system observed in the cat,"
 +
 +
So far as I know, an anomaly of this particular type has not before been reported. Undoubtedly, however, when the full report of the embr^'ological evidence collected b}' Huntington and AlcClure is published, this case will fall into its proper place as one of the variants due to the atypical persistence of embryonic channels.
 +
 +
BIBLIOGRAPHY
 +
 +
Darrach, William \'ariations in the postcava and its tributaries as observed in 605 examples of the domestic cat. Anat. Rec. vol. 1, p. 30.
 +
 +
HuxTixGTOx, George S., and McClure, C. F. The interpretation of variations of the postcava and tributaries of the adult cat, based on their development. Anat. Rec. vol. I. p. .33.
 +
 +
 +
 +
Resumido j^tor el alitor, Harrison R. Hunt.
 +
 +
Anonialias vasculares en un gato domestico (Felis domestica).
 +
 +
Las anomalias vasculares descritas a continuaci6n han sido observadas en un gato adulto. Las del sistenia venoso eran: Una postcava izquierda, venas renales dobles en cada lado, un orificio en la vena iliolumbar izcjuierda a traves del cual pasa la arteria correspondiente, vena esperniatica izquierda ramificada desde la postcava y la misma vena del lado derecho ramificada desde una de las venas renales derechas. El ureter estaba rodeando a la postca\a. En el sistema arterial, el arco aortico estaba situado en el lado derecho y la arteria innominada en el izquierdo; desde esta ultima se ramificaba la arteria carotida comiin y la subclavia izquierda, mientras que la subclavia derecha arrancaba de la base del cayado de la aorta.
 +
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Translation by Jos6 F. Nonidez Columbia University
 +
 +
 +
 +
ATTTHOR S ABSTRACT OF THIS PAPER ISSIED BY THE BIBLIOGRAPHIC SERVICE, MARCH 17
 +
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VASCULAR ABXOR^^IALITIES IX A DO^^IESTIC CAT (FELIS DOMESTICA)
 +
 +
HARRISON R. HUNT West Virginia University
 +
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ONE FIGURE
 +
 +
Recently the writer dissected, a male cat which presented so many interesting vascular anomalies that publication of the facts seemed justified. The accompan34ng figure is a semidiagrammatic representation of the main blood-vessels of this anmial as seen from the ventral side.
 +
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Posterior to the superior mesenteric artery (12) thepostcava (9) was situated at the left of the aorta (10) A The left ureter (28) looped around the postcava in the manner shown in the figure. The position of the spermatic vems was the reverse of the normal position, the left spermatic (23) branching from the postcava (9), while the right (20) emptied into the posterior right renal vein (17).
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Other observers have reported similar abnormalities in the cat. Darrach ('07) has described three cases in which the relations of the postcava, ureter, and sex veins were practically the same as m this individual. ]\IcClure COO) figures (fig. 3) a case in which each ureter looped around the persistent postcardinal vein, as the left ureter passed around the postcava in the accompanying figure. Hochstetter ('93) mentions one cat in which the postcava lay at the left of the aorta posterior to the superior mesenteric artery, and a second case (having two persistent postcardinal veins) in which each ureter looped around a postcardinal.
 +
 +
Two renal veins (l7 and 19) drained each kidney' (14)- Double renal veins were observed by AlcClure also ('00) in the cat.
 +
 +
' Unfortunately, my records do not show whether the superior mesenteric and coeliac arteries were on the right or the left side of the postcava.
 +
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88 HARIUSOX K. HUNT
 +
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The loft ilioliiiiibar artery (26) passed clorsally throiip;h a foramen in the left iliolinnbar vein. Such venous foramina have been rejiorted by several other observers (Darrach, '07; ]\IcC'lure, '00; Treadwell, '96; Weysse, '03; Smalhvood, '06).
 +
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The ex])lanation for these anomalies in the venous system must be sought hi embryology. ]\Iost of the distal portion of the left postcardinal vein in the cat embryo normally degenerates anteriorh' to the level at which the left spennatic vein branches ofif (Hochstetter, '93, '06). On the other hand, the right postcardinal vein persists, becoming part of the postcava. Normally, the right spennatic vein pennanently maintains its embryonic connection with the right ]:)ostcardinal. But apparenth^ in this animal the postrenal part of the left postcardinal, instead of the right, persisted as part of the postcava. Consequently the left spermatic vein retained its embryonic relation ^^ ith the left postcardinal.
 +
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Proba})h' the right postcardinal of this animal degenerated anteriorly as far as the right spermatic vein, so that the latter became a branch of the right renal.
 +
 +
Hochstetter's ('93, '06) observations on the development of the cat's veins show clearly why the left ureter encircled the postcava in this anmial. In the cat embryo each ureter is surrounded, at a certain stage, by a ^'enous island, consisting dorsally of a supracardinal vein, ventrally of the postcardinal (Prentiss, '15, fig. 274). In the cat, according to Hochstetter, and in other mammals only the dorsal, or supracardinal, limb of this island ]:)ersists as a part of the postcava. In this particular cat, and in shnilar cases which have been reported, doubtless the supracardinal limb of the island degenerated, and the postcardinal Umb survi\-cd as a part of the ]iostcava, causing the ureter to pass around the dorsal side of the postcava (jMetcalf, '18).
 +
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Probably the most infrequent abnormality hi this cat was the position of the aortic arch. Normally it lies on the left side of the annual, but in this case it was on the right side. The left subcla\'ian artery (4), instead of connecting directly as usual with 1he aortic arch, came from the distal end of the unusually short innominate artery. The right subchuian ((1) ])ranched
 +
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 +
 +
VASCULAR ABNORMALITIES IN DOMESTIC CAT
 +
 +
 +
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89
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 +
Fig. 1 Ventral view of the arterial and venous systems. The hepatic veins have been omitted. 1, left innominate vein; 2, precava; 3, left common carotid artery; 4, left subclavian artery; 5, right common carotid artery; 6, right subclavian artery; 7, azygos vein; 8, heart; 9. postcava; 10, aorta; 11, celiac axis; 12, superior mesenteric artery; 13, right adrenohunbar vein; H, left kidney; 25. left adrenolumbar vein; 16, right renal artery; 17, right renal veins; 18, left renal artery; 19, left renal veins; 20, right spermatic vein; 21, right spermatic arterj-; 22, left spermatic artery; 23, left spermatic vein; 2^, inferior mesenteric artery; 25, iliolumbar vein; 26, iliolumbar artery; 27, right ureter; 28, left ureter.
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 +
 +
THE ANATOMICAL RECORD, VOL. 16, NO. 2
 +
 +
 +
 +
90 HARRISON R. HUNT
 +
 +
from the aortic arch at the base of the innominate. In man also the aortic arch occasionally occurs on the right side (Cunnmgham, '09).
 +
 +
Manmialian embrj^ology furnishes an explanation for the anomalous position of this arch. In the nonnal development of mammals the right fourth arch degenerates, leaving the left fourth arch to carry the blood from the heart. Probably the left fourth arch of this annual degenerated, as in birds, leaving the arch on the right side as the permanent blood channel.
 +
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It would be interestmg to know whether these vascular abnormalities were due to hereditary or environmental influences, to one cause or to a chance combination of several independent causes. All these anomalies were not produced by the disappearance or unusual modification of the normal activity of one ]\Iendelian factor, for all these abnormalities seldom occur together in one animal. Nevertheless, the riormal and abnormal conditions of these vessels may possibly be Mendelian characters, the occurrence of so many abnormalities in one animal being a very unusual chance combination of characters.
 +
 +
Or, possibly, the developing embryo was subjected to unusual environmental conditions, such as abnormal amounts of certain substances in the mother's blood. These conditions may have slightly modified the development of the body as a whole, but produced most pronounced abnormalities in the blood system. Investigations in genetics or experimental morphology might furnish a satisfactory explanation.
 +
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Morgantown, West Virginia, December 6, 1J!18
 +
 +
 +
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VASCULAR ABNORMALITIES IN DOMESTIC CAT 91
 +
 +
LITERATURE CITED
 +
 +
CrxxiXGHAM, D. J. 1909 Text -book of anatomy. Third edition. Win. Wood
 +
 +
& Co. Darrach. W. 1907 Variations in the postcava and its tributaries as observed
 +
 +
in 605 examples of the domestic cat. Anat. Rec, vol. 1, p. 30. HocHSTETTER, F. 1893 Beitriige zur Entwickelungsgeschichte des Venensys tems der Amnioten. Ill Sauger. Morph. Jahrb., Bd. 20, S. o43-M8. 1906 Die Entwickelung des Blutgefasssystems. In Handbuch der Vergleich enden und Experimentellen Entwickelungslehre der Wirbeltiere. G.
 +
 +
Fischer, Jena. Bd. 3, Teil 2, S. 21-166. McClure, C. F. W. 1900 On the frequency of abnormalities in connection with
 +
 +
the postcaval vein and its tributaries in the domestic cat (Felis domes tica). .\m. Xat., vol. 34, pp. 185-198. Metcalf, H. E. and K. D. 1918 Persistence of the posterior cardinal veins in
 +
 +
an adult cat. Anat. Rec, vol. 14, no. 1. pp. 123-126. Frextiss, C. W. 1915 Text-book of embryology. W. B. Saunders Co. Smallwood, W. M. 1906 Some vertebrate abnormalities. Anat. Anz., Bd. 29,
 +
 +
Xo. 16 und 17, S. 460-462. Tread WELL, A. L. 1896 An abnormal iliac vein in a cat (Felis domestica).
 +
 +
.\nat. Anz., Bd. 11, No. 23 und 24, S. 717-718. Weysse, a. W. 1903 The perforation of a vein by an artery in the cat (Felis
 +
 +
domestica). Am. Nat., vol. 37, pp. 489-492.
 +
 +
 +
 +
Resumido por el autor^ Ezra Allen.
 +
 +
Degeneraci6n eii el testiculo de la rata albina a consecuencia de
 +
 +
una dieta deficiente en la vitamina soluble en el agua, con
 +
 +
una comparaci6n de una degeneracion semejante en
 +
 +
ratas tratadas de un modo diferente y una con sideracion sobre el tejido de Sertoli.
 +
 +
Las ratas albinas sometidas por Osborne y JVIendel a una dieta deficiente en la vitamina soluble en el agua son esteriles. El examen de los testiculos ha demostrado la degeneracion completa de las cclulas germinales. Tan solo persisten en los tiibulos las celulas de Sertoli, si bien sus nucleos aparecen muy contraidos. El tejido intersticial estaba hipertrofiado. Estos caracteres son los mismos que se encuentran en los testiculos de otros mamiferos sometidos a la accion de los rayos X. Una degeneracion semejante ha sido observada tambien en algunas ratas alcoholizadas por MacDowell, degeneraci6n que se presentaba tambien, aunque en menor grado, en los hermanos de dichas ratas que no fueron sometidos a la acci6n del alcohol. Bajo estas condiciones el tejido de Sertoli revela una estructura sincicial (jue el autor del presente trabajo considera como el estado normal, como demuestra el material bien fijado.
 +
 +
Translation by Jo86 F. Nonidez Columbia University
 +
 +
 +
 +
author's abstract of this paper issued by the bibliographic service, march 17
 +
 +
 +
 +
DEGENERATION IN THE ALBINO RAT TESTIS DUE TO A DIET DEFICIENT IN THE WATER-SOLUBLE VITAMINE, WITH A COMPARISON OF SIMILAR DEGENERATION IN RATS DIFFERENTLY TREATED, AND A CONSIDERATION OF THE SERTOLI TISSUE
 +
 +
EZRA ALLEN
 +
 +
The Wistar Institute of Ana'.omy and Biology
 +
 +
SEVEXTEEX FIGURES
 +
 +
CONTENTS
 +
 +
1 Introduction 93
 +
 +
2. The material 94
 +
 +
3 Technique 95
 +
 +
4. Observations upc n the Osborne and Mendel rats 96
 +
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Normal Sertoli tissue 96
 +
 +
The Sertoli tissue in the degenerate tubules 97
 +
 +
Other structures 98
 +
 +
The progress of degeneration J.00
 +
 +
The interstitial tissue 101
 +
 +
5. Observations upon the ^LacDowell rats 102
 +
 +
Degeneration in the iMacDowell rats 102
 +
 +
The order of degeneration among the germ cells 104
 +
 +
The interstitial tissue 104
 +
 +
6. Conclusions with regard to the two sets of rats 104
 +
 +
7. Discussion 10.5
 +
 +
The Sertoli tissue as a syncytium 107
 +
 +
The Sertoli nucleolus 108
 +
 +
The interstitial tissue 110
 +
 +
Physiological considerations 1 10
 +
 +
S. Summary Ill
 +
 +
9. Literature cited 112
 +
 +
10. Explanation of the plates 113
 +
 +
INTRODUCTION
 +
 +
This paper deals with a similar type of degeneration found in the testes of two groups of albino rats which had been subjected to very different treatment. The histological and cytological
 +
 +
93
 +
 +
 +
 +
94
 +
 +
 +
 +
EZRA ALLEN
 +
 +
 +
 +
conditions revealed upon examination are of sufficient interest for description not only for the light they throw upon certain problems connected with the Sertoli tissue, but also because they indicate the value of further experiments along the lines of their causes.
 +
 +
THE MATERIAL
 +
 +
I am indebted to Professors Osborne and ]\Iendel for one lot of rats and to Dr. E. C. MacDowell, of the Carnegie Station for Experunental Evolution at Cold Spring Harbor, for the other. There were four in the first lot and ten in the second group. For convenience I will refer to the two lots as the Osborne and ^Mendel and the ^'klacDowell rats.
 +
 +
The first lot were chosen at random from a larger group which had been subjected to a diet deficient in the water-soluble vitamine. All of these rats, both male and female, had proved sterile. Aside from their sterility they were very well developed. The data of especial interest as to their development will be found in table 1.
 +
 +
The ^NlacDowell rats came from a lot which have been referred to, in a paper pubUshed by MacDowell and Vicari ('17) dealing with reduction in fertilitj^ among rats subjected to alcohol. Five of the alcoholized rats, from five different litters, and their normal brothers were sent to me. The alcoholics had been made drunk daily beginning at twenty-eight days of age. Each treatment was continued long enough to produce not only
 +
 +
TABLE 1
 +
 +
Shoving the body measurements, comparison of weight of testes with standard on body length, and age at death of the Osborne and Mendel rats
 +
 +
 +
 +
 +
 +
 +
 +
 +
 +
 +
 +
 +
 +
STANDARD
 +
 +
 +
 +
 +
NLMBEB
 +
 +
 +
WEIGHT
 +
 +
 +
LENGTH OF BODY + TAIL
 +
 +
 +
LENGTH OF BODl
 +
 +
 +
WEIGHT OF TESTES
 +
 +
 +
OF TESTES ON
 +
 +
BODY
 +
 +
LENGTH
 +
 +
 +
AGE AT DE.\TH
 +
 +
 +
 +
 +
grams
 +
 +
 +
THTn,
 +
 +
 +
mm.
 +
 +
 +
grams
 +
 +
 +
grams
 +
 +
 +
tnonlhs
 +
 +
 +
3554
 +
 +
 +
316
 +
 +
 +
400
 +
 +
 +
230
 +
 +
 +
0.975
 +
 +
 +
2.278
 +
 +
 +
24
 +
 +
 +
3610
 +
 +
 +
325
 +
 +
 +
438
 +
 +
 +
237
 +
 +
 +
0.690
 +
 +
 +
2.926
 +
 +
 +
22
 +
 +
 +
3756
 +
 +
 +
348
 +
 +
 +
397
 +
 +
 +
218
 +
 +
 +
0.851
 +
 +
 +
2.525
 +
 +
 +
20
 +
 +
 +
3896
 +
 +
 +
288
 +
 +
 +
414
 +
 +
 +
222
 +
 +
 +
1.334
 +
 +
 +
2.609
 +
 +
 +
18
 +
 +
 +
 +
DEGENERATION IN THE RAT TESTIS 95
 +
 +
inability to stand, but frequently to render the rats absolutely motionless. This meant long treatments, since as they became habituated they could stand larger and larger amounts before they succmiibed.
 +
 +
All ten had been subjected to a special diet for fifteen days, beginning when they were sevent}^ days of age. It consisted solely of white bread soaked in fresh milk. The rats were allowed to eat of it for thirty minutes the first two days, for fifteen minutes the next five days, and for five to ten minutes the next eight days.
 +
 +
Data for these rats, corresponding to those for the Osborne and [Mendel lot, are to be found in table 2.
 +
 +
TECHNIQUE
 +
 +
The two sets of rats were treated substantially alike, although the MacDowell rats were killed in May, 1917, and the Osborne and Mendel in April, 1918. After etherization they were measured and weighed. The testes were then removed and, with the exception of Osborne and Mendel's nos. 3554 and 3756, dropped into the fixative, B-15 at about 38°C., after being cut into small pieces by scissors. The fixative had been weighed previously, so that a second weighing with the testes in it gave data for determining their weight. The two rats, nos. 3554 and 3756, were injected by the fixative after washing out the bloodvessels with Locke's solution. For the sake of unifomiitj^ in weights, the testes of all the Osborne and ]\Iendel rats were weighed after fixation.
 +
 +
The fixative was replaced with 70 per cent alcohol by the drop method, the picric acid washed out with the help of lithium carbonate in 70 per cent alcohol, and dehych"ation completed in anilin oil. Clearing was by oil of wintergreen. Both oils were added by the drop method. Infiltration by paraffin was brought about very gradually. Details of this treatment are described in my paper on technique (Allen, '16). Sections were cut at 7/x and lO/i and stained with iron haematoxylin and acid fuchsin or orange G.
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 +
 +
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96 EZRA ALLEN
 +
 +
OHSERVATIOXS UPON THE OSBORNE AND MENDEL RATS
 +
 +
In the case of all four rats the tunica albuginea was found to have an excess of a clear, sciTiin-likc fluid, which flowed out as soon as the tunic was ruptured. The solid part of the testes was much shrunken. The fluid had distended the organs so that they looked quite nonnal before the tunic was ruptured.
 +
 +
Ujjon examination of the sections certain conditions common to all four were revealed. Some minor variations in the different indi\'i{luals were present. The common conditions will be described flrst. These may be enumerated as 1) no mature spermatozoa; 2) almost no normal germ cells in any stage; 3) generally speaking, an absence of spermatogonia, spermatocytes, and spemiatids; 4) the Sertoli tissue the most prominent of any tissue in the tubules, and 5) an increased quantit}' of interstitial tissue as compared with the normal.
 +
 +
An idea of the general appearance of the tubules and the interstitial tissue may be had by examining figures 2 and 9. It will he noted that the germinative epithelium is ahiiost entirely lacking or very abnormal, the latter state due to the presence of numerous cavities. Figures 5 and 6 show these conditions better. Sometimes the tubules are apparently solid, no lumen appearing, and the cavities just referred to either lacking entirely or, if present, very small (figs. 1 and 8). In either case the contents of the tubules are composed chiefly of Sertoli nuclei and their syncytial cytoplasm.' Since this tissue is the most prominent, it will be described first, after a brief consideration of its normal structure.
 +
 +
Normal Sertoli tissue
 +
 +
In normal tubules the syncytium is difficult to see, on account of the closely packed germ cells, but under favorable conditions in the section very small areas may be discerned. Close to the Sertoli nuclei the cytoplasm is clearly observable, but no cytoplasmic walls are to be seen. In character the syncytial cytoplasm in Vjoth the normal and in these degenerate conditions resembles the substance which fills the tubules in the early
 +
 +
 +
 +
DEGENERATION IN THE RAT TESTIS 97
 +
 +
stages of their development. See my figures 2 to 8, Allen ( 18). In the adult it is best seen when the groups of spermatozoa have nearl}^ matured and are migrating toward the lumen from the immediate neighborhood of the Sertoli nuclei along the basement membrane. These groups of spermatozoa then seem to have dragged with them some of the Sertoli cytoplasm, which under favorable conditions may be seen extending nearly across the. entire width of the germinal epithelium. It is distinguished by its coarse nature and its heavy staining character. Even then no cytoplasmic wall is visible. This appearance is shown in figure 14.
 +
 +
The Sertoli nuclei are nearly always in close relationship with the basement membrane (fig. 14). They may be distinguished by the nucelolus, which is well illustrated in figures 14 to 17, and by the less active reaction of the nuclear plasm to haematoxylin as compared with that of the spermatogonia.
 +
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The Sertoli tissue in the degenerate tubules
 +
 +
To return now to the degenerate tubules under consideration: the nuclei are irregular in outline, due to their membranes having wrinkled and formed grooves of various sizes (figs. 11 to 13). Several small bodies staining like chromatin are present. Two, twin-like, are the most prominent. These are shown in figures 11 and 13. In the normal Sertoli nuclei these bodies are very unequal in size, as shown in figures 14 to 17. Intermediate stages have been traced between the normal and degenerate condition with respect to this duplex body, so we may be confident that such nuclei as shown in figures 1.1 and 13 are Sertoli cell nuclei.
 +
 +
In such a stage of degeneration as shown in figure 6, these nuclei are very numerous and are scattered throughout the tubule. In the more advanced stage, as illustrated in figure 5, they are confined to the periphery, and are reduced in size and in number. A rough idea of this diminution may be obtained by a comparison of the tubules photographed for figures 5 and 6. They are from the same section, which was cut at 7m.
 +
 +
 +
 +
98 EZRA ALLEN
 +
 +
In the tubule shown in figure- 6, fifty-one nuclei are to be counted in the section; in the one shown in figure 5, thirteen are present. In neither case are any other kinds of cells to be seen within the tubules. The true germ cells have completely disappeared.
 +
 +
The cj'toplasmic substance stains with orange G and with acid fuchsin more lightly than the same substance in the young tubule, but seems very similar in structure. It may be described as a loose meshwork, the substratum of which seems to be minute, irregular 'granular' bodies, the same sort of substance as found in the normal Sertoli cytoplasm. It is either continuous, except as interrupted ' by the nuclei, or broken by cavities, figures 3 B, 6, 8, 9, and 11.
 +
 +
In one respect it differs somewhat from the cytoplasm of the nonnal Sertoli tissue, or of the young tubule, in that it seems somewhat stringy or thready. This appearance is partly due to degenerate spermatozoan tails and partly to the tendency of the sjTicytial substance itself to form a more or less fibrous structure, which bears some resemblance to the fibers of connective tissue, but is much more dehcate and less sharply defined. In figure 11 , this characteristic is to be noted, particularly in the lower lefthand corner. In the normal tissue, when the spermatozoan heads have migrated well toward the lumen, this appearance is suggested to the observer, although the stringiness is much less well defined.
 +
 +
Other structures
 +
 +
From the quantitative, point of view, the next structures to be described are the unmature spermatozoa. These may be so abundant as to divide the space about equally with the Sertoli tissue or they may be relatively few. In the former condition they give to the tubule the appearance illustrated in figures 1 and 7. With higher magnification such a tubule appears to be filled with a more or less fibrillar mass intermingled with a granular substance, the whole taking any stain lightly, scattered through which the shrunken Sertoli nuclei are quite abundant (fig. 6). The fibrillar portions resolved into tails of spermatozoa, the heads of which, only partially formed, do not
 +
 +
 +
 +
DEGEXERATIOX IX THE RAT TESTIS 99
 +
 +
stain prominently with nuclear stains. These immature spermatozoa are in bundles or groups, but so intermingled that it is out of the question to determine whether the number in each bundle is less or greater than normal.
 +
 +
In this type of degenerative condition, canities appear which vary in size from one equal to two or three Sertoli nuclei to one whose diameter is half that of the tubule or even greater (^figs. 6 and 7). Usually, however, with the increase in size of these canities the immature spermatozoa disappear. There are also to be seen degenerate nuclei of a type other than those pre^^ously described. These are of various sizes, some smaller and some larger than the Sertoh nuclei. Thej- stain yellowish in the iron haematoxylin and acid fuchsin preparations. Their contents consist of granular masses of unequal size, more or less densely aggregated. The medimn-sized ones may have a clear space between such a unified mass and the nuclear membrane. Xo C3i:oplasm is discernible. Their identification is doubtful. They may be either remains of spermatid nuclei or degenerating Sertoh nuclei. That they may be the latter is indicated by the numerical relationships already referred to on page 98.
 +
 +
In this connection an indiA'idual difference in the case of one rat, no. 3554, may be noted. Degeneration seemed unifonn but incomplete. In nearly everv^ tubule the condition was that just described, that is, the tubules filled with the mixture of Sertoli tissue, the immature spermatozoa, and degenerate nuclei which stain yellowish. It is tj-pically shown in figures 1 and 8. Scarcely a tubule was found showing degeneration to the degree illustrated in figure 5, and only a few with cavities as large as in figure 6. Xo spennatogonia, spermatocj'tes or spermatids were found. Along the basement membrane, however, in a very few tubules dividing cells are present, one 'or two to a tubule per section. These cells resemble di^iding spermatogonia or the undifferentiated embrA^onic nuclei.
 +
 +
In the dividing cells just referred to the chromosomes and spindle are normal. One case of another type of diAiding cell was seen, situated similarly, in which the chromosomes while abnormal resemble the first spermatocyte metaphase forms,
 +
 +
 +
 +
lUO EZRA ALLEN
 +
 +
although the stage of division cannot be positively determined. No idiosome nor chromatoid body appears.
 +
 +
In the case of the other rats, cell division was rare in no. 3610, and abnormal: it was more abundant in no. 3896, and often normal. It was found in the ceils along the basement membrane. Some cell division was observed in no. 3756, also along the marginal layer of cells. The chromosomes were normal and characteristic of spermatogonia in anaphase. In a tubule showing degeneration advanced to that typical of no. 3554, one such cell was found.
 +
 +
The degeneration in rat no. 3554 is much more uniform than in the others. The least uniform was no. 3756. Figure 3 shows that adjoining tubules may differ widely in this testis. Tubule A is practically normal; B has reached the stage a little later than that characteristic of no. 3554, while C is in the last stage obser\-ed. Only four tubules as nearly normal as A were found. This condition is therefore exceptional.
 +
 +
In no. 3896 more spermatocytes in early stages of development were found than in any other. These cells seemed to be normal. Growth has in some cases reached the leptotene stage. In the tubules showing these spermatocytes no immature spermatozoa were to be seen, but the wrinkled Sertoli nuclei were scattered freely in their characteristic cytoplasmic substance, and in some cases many cavities of large size appeared.
 +
 +
Occasionally pycnotic nuclei have been found in both the germinal and the interstitial tissue, but these are likely to be found in normal tissue. It is difficult to say whether the number of these in this degenerating tissue is more or less than the normal, as considerable variation exists in the normal. It has not impressed me as abnormal. In fact, I have been surprised that degeneration has taken that form so seldom.
 +
 +
The progresfi of degeneration
 +
 +
From the foregoing observations it would seem that degeneration had begun in the different individuals at different times or that different tubules reacted very differently to the diet. The condition found in no. 3554 would indicate that degeneration
 +
 +
 +
 +
DEGENERATION IN THE RAT TESTIS 101
 +
 +
had not begun until the spermatozoa had started to form, after which all the other germ cells had degenerated. Whether this lot of immature spermatozoa represent the first crop, which has persisted through the degeneration of the other germ cells, or the second or a later crop cannot be determined from the condition of the testes at death.
 +
 +
The uneven degeneration found in no. 3756 indicates that certain tubules were almost immune to the condition which brought' about degeneration. These tubules are, however, very few indeed, so few that perhaps the}' may almost be neglected. At the same time the tubule shown in figure 3, A, shows all stages of spermatogenesis up to the spermatid formation. A similar stage in j'oung material is normal.
 +
 +
In the case of rat no. 3896, in which complete degeneration of the germ cells and great reduction of the Sertoli nuclei were the rule, some tubules showed spermatocytes as far advanced as the leptotene stage. This last-named condition would indicate that for some reason these particular spermatocytes had been preserved during the degeneration of the Sertoli nuclei. It is not likely that they could have advanced much farther in their development. Certainly, the spermatozoa could not mature upon such pathological nurse ceUs.
 +
 +
The interstitial tissue
 +
 +
As pre\iously noted, the interstitial tissue is relatively much greater than in the normal. This abundance is well shown in figures 1 and 2. The only cytological abnormality is that many of the glandular nuclei are slightly irregular in outline, often shrunken considerably. They react equally to the stain, while often in normal testes the reaction is quite unequal. Rat no. 3554 showed the shrunken and irregular nuclei much more abundantly than any of the others. In all the rats the amount of connective tissue seems about the same and quite normal. The endothelial nuclei are also normal. The interstitial tissue is unequally distributed, in some cases occurring in large masses. See figure 1 near the blood-vessel. Dividing cells are occasionally found.
 +
 +
 +
 +
102 EZRA ALLEN
 +
 +
OBSERVATIONS UPON THE MacDOWELL RATS
 +
 +
These rats, like the Osborne and ^Mendel lot, were in general about normal in development, with the exception of the testes of the five alcoholics, three of which, as shown by table 2, were under weight, one about normal, and one (no. 764) considerably over weight. In body weight based upon l)ody length, there is a slight variation from the standard, from eleven under to fifteen grams over weight among the entire number. ,0n the whole, the alcoholics ran a little over weight. The only two under weight were nos. 687 and 767, respectively eleven and five grams.
 +
 +
Degeneration in the MacDowell rats
 +
 +
The degeneration in these rats, while similar in kind to that of the Osborne and jMendel lot, varied greatly in degree in the different "rats. Some testes were almost or quite normal, others shghtly abnormal, while one showed almost as advanced a stage as that of the Osborne and Mendel rats. Unlike the first lot, however, degeneration of any degree had not extended equally- throughout the organ. It was confined to certain portions only, like islands in normal tissue, these varying in size. They were most numerous and largest in no. 704. In fact, very little of this rat's germinal tissue was normal.
 +
 +
The final stage, when present, is confined to small portions of the tubule concerned, unless degeneration has progressed to a very advanced stage, as in no. 704, in which case considerable lengths of the tubule are involved. This last-named condition is shown in figure 7, the tubules in which are representative of the testis from which it was taken, no. 704.
 +
 +
In the early stage, the signs of degeneration are confined to small cavities which appear in the germinative wall, such as shown in figure 10, C. At a little later these cavities have enlarged and appear as in figure 7, C. At a later stage still, the cavities have enlarged, the germ cells are scattered through the lumen and are abnormal in various ways. The Sertoli nuclei usually remain near the basement membrane, but in advance stages are always to be found there. The Sertoli cytoplasm is shreddy and fills the
 +
 +
 +
 +
DEGEXEKATIOX IX THE RAT TESTIS
 +
 +
 +
 +
103
 +
 +
 +
 +
TABLE 2
 +
 +
 +
 +
Shouing in A the body measurements, comparison of weight of testes with standard on body length, length of alcohol treatment, age when begun, age at death, and degree of degeneration of the MacDoivell rats, and in B the corresponding data for the normal brothers
 +
 +
 +
 +
 +
 +
 +
 +
 +
 +
STAND
 +
 +
AGE
 +
 +
 +
LENGTH
 +
 +
 +
LENGTH OF BODY
 +
 +
 +
WEIGHT
 +
 +
 +
ARD
 +
 +
 +
WHEN
 +
 +
 +
OF BODY
 +
 +
 +
OF
 +
 +
 +
WEIGHT
 +
 +
 +
ALCOHOL
 +
 +
 +
+ TA1L
 +
 +
 +
TESTES
 +
 +
 +
OX BODY
 +
 +
 +
WAS
 +
 +
 +
 +
 +
 +
 +
 +
 +
LENGTH
 +
 +
 +
BEGCN
 +
 +
 +
 +
LENGTH
 +
 +
OF AGE AT
 +
 +
TREAT- DEATH ME NT
 +
 +
 +
 +
DEGREE OF DEGENERATION
 +
 +
 +
 +
 +
 +
grams
 +
 +
 +
Tnm.
 +
 +
 +
mm.
 +
 +
 +
grams
 +
 +
 +
grams
 +
 +
 +
days
 +
 +
 +
days
 +
 +
 +
days
 +
 +
 +
 +
 +
614
 +
 +
 +
198
 +
 +
 +
391
 +
 +
 +
201
 +
 +
 +
2.052
 +
 +
 +
2.094
 +
 +
 +
43
 +
 +
 +
155
 +
 +
 +
225
 +
 +
 +
Slight
 +
 +
 +
686
 +
 +
 +
171
 +
 +
 +
372
 +
 +
 +
192
 +
 +
 +
2.124
 +
 +
 +
1.964
 +
 +
 +
28
 +
 +
 +
97
 +
 +
 +
162
 +
 +
 +
Slight
 +
 +
 +
704
 +
 +
 +
122
 +
 +
 +
334
 +
 +
 +
163
 +
 +
 +
1.914
 +
 +
 +
1.313
 +
 +
 +
38
 +
 +
 +
83
 +
 +
 +
158
 +
 +
 +
Extreme
 +
 +
 +
725
 +
 +
 +
142
 +
 +
 +
347
 +
 +
 +
176
 +
 +
 +
1.963
 +
 +
 +
1.609
 +
 +
 +
28
 +
 +
 +
83
 +
 +
 +
148
 +
 +
 +
^Medium
 +
 +
 +
764
 +
 +
 +
191
 +
 +
 +
370
 +
 +
 +
196
 +
 +
 +
1.778
 +
 +
 +
2.951
 +
 +
 +
28
 +
 +
 +
77
 +
 +
 +
142
 +
 +
 +
Medium
 +
 +
 +
 +
 +
 +
 +
 +
 +
 +
 +
 +
 +
 +
 +
 +
Normal brother
 +
 +
 +
 +
 +
 +
 +
 +
 +
 +
 +
 +
 +
 +
 +
 +
 +
 +
 +
of
 +
 +
 +
 +
 +
 +
 +
618
 +
 +
 +
279
 +
 +
 +
422
 +
 +
 +
220
 +
 +
 +
2.075
 +
 +
 +
2.567
 +
 +
 +
614
 +
 +
 +
225
 +
 +
 +
Xormal
 +
 +
 +
687
 +
 +
 +
269
 +
 +
 +
410
 +
 +
 +
222
 +
 +
 +
2.574
 +
 +
 +
2.609
 +
 +
 +
686
 +
 +
 +
162
 +
 +
 +
Slight
 +
 +
 +
707
 +
 +
 +
211
 +
 +
 +
380
 +
 +
 +
202
 +
 +
 +
2.822
 +
 +
 +
2.181
 +
 +
 +
704
 +
 +
 +
158
 +
 +
 +
Medium
 +
 +
 +
727
 +
 +
 +
185
 +
 +
 +
350
 +
 +
 +
192
 +
 +
 +
2.240
 +
 +
 +
1.964
 +
 +
 +
727
 +
 +
 +
148
 +
 +
 +
Slight
 +
 +
 +
767
 +
 +
 +
210
 +
 +
 +
394
 +
 +
 +
206
 +
 +
 +
2.049
 +
 +
 +
2.267
 +
 +
 +
764
 +
 +
 +
,142
 +
 +
 +
Slight
 +
 +
 +
 +
interstices between the germ cells, just as in the Osborne and Mendel specimens, presenting the same appearance as that sho\\Ti in figure 6, or, for the most advanced stages, as that shown in figure 5. The vSertoli nuclei are not as shrunken and wrinkled as in the Osborne and Mendel specimens, nor is the nucleolus so markedly different from the normal, seldom showing an appearance like that in figure 13.
 +
 +
In many places cells in various conditions appear, some normal, some polynuclear, some degenerating by pycnosis and others by a process in which the chi'omatin occurs in very small, lightly staining granules, yellowish in color with haematoxylin. Many of these may be identified as first sperinatoc3d:es, some in the growth stages and others in di\ision. Giant cells occur frequently in the earlier stages of degeneration.
 +
 +
 +
 +
104 EZRA ALLEN
 +
 +
The tubules which show ad\'anced degeneration are smaller in diameter than the normal, although this difference in size is not always as great as shown in figures 7 and 10.
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The order of degeneration among the germ cells
 +
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In order of degeneration the spermatocytes seem to be the first affected, the spermatids next, and the spermatogonia last, although in some places the early growth stages of the first spermatocytes are found with spermatogonia, but no spermatids. In many places the spermatogonia persist along the basement membrane along with the Sertoli nuclei, but all other germ cells have disappeared. Under these conditions these spermatogonia nuclei are somewhat shrunken and wrinkled. I have not determined whether the second spermatocj'tes are more susceptible than the first.
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The interstitial tissue
 +
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In these animals the quantity of interstitial tissue does not seem to be increased, nor have any shrunken muclei been noted even in the most advanced degenerate conditions of the tubules. Further experiments are needed to demonstrate why this difference in this respect should appear between the two sets of rats when the germinal tissue is affected in a like manner.
 +
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COXCLUSIOXS WITH REGARD TO THE TWO SETS OF RATS
 +
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The facts just set forth show that certain agents have a selective action upon the development of the germ cells. From the Osborne and Mendel rats we must conclude that for normal growth of these cells a diet containing a generous supply of the water-soluble vitamine is an essential. Just how much remains to be determined by further experiment.
 +
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From the MacDowell rats ^studied, a conclusion is not so easily drawn since two factors entered into their history. They were all subjected to a reduced diet for fifteen days, beginning when they were ten weeks of age, while half of them were also subjected to the fumes of alcohol for a period long enough to
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DEGEXERATIOX IX THE RAT TESTIS lOo
 +
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produce complete intoxication daily during a time vaning from seventy-seven to one hundred and fifty-five days. Neither of these treatments interfered with these rats' producing offspring, although the whole group of alcoholics from which they were taken showed a considerable reduction in fertilitj^ QIacDowell and Vicari, '17), to the extent that twenty-nine pairs of normals produced 300 3'oung, while during the same time thirty pairs of alcoholics produced only 108 young. How far the male is responsible does not yet appear, but it is clear that in the ten rats of the series which came to me the degeneration is consistently greater in the alcoholics than in their control brothers, both from the extremes and from the average, as is brought out in table 2.
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Under the circumstances, it is unwise to draw any general conclusions as to the cause of the degeneration in these QIacDowell rats. TMiat does seem clear from a comparison of the two lots under consideration is that similar conditions of degeneration may arise in the testes of rats subjected to widelj^ different treatments, and that the immediate causes affecting growth and cell division in the germ cells may be identical.
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DISCUSSIOX
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The discussion is divided naturally into anatomical and physiological considerations. With respect to the former, the chief interest centers about the tyipe of degeneration and the light it throws upon the Sertoli tissue.
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The type of degeneration is not new. Regaud ('01) describes similar conditions in the tubules of the white rat near their distal extremities, but does not state a cause. The same author ('10) and Barratt and .Irnold ('11) find a similar type of degeneration in mammahan testes which have been subjected to x-rays. Colwell and Russ Tlo) have assembled the effects of x-ray treatment upon tissues and note nothing dift'erent in connection with the testis. They quote chiefly Regaud and the work of Barratt and Arnold, just referred to, and reproduce the latter's figure 30 as their figure 40.
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THE ANATOMICAL RECORD, VOL. 16. XO. 2
 +
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106 EZRA ALLEN
 +
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Regaud ('10) worked with nibbit, guinea-pig, mouse, cat, and rat, and obtained essentially similar results with all. His figure (from eat) shows a condition practically identical with my figure 5. Barratt and Arnold ('11) used the rat. Their figures 30 and 31 represent the same phenomena as my figures 11 and 6, respectively. The descriptions given by the three authors just quoted indicate that there is no difference in the final histological picture — total destruction of the germ cells, the Sertoli tissue alone remaining within the tubules. Barratt and Arnold claim an increase in the number of Sertoli nuclei found in the final stages as compared with the earlier, but give no diata upon which such a conclusion has been based. ]\Iy own observations indicate the reverse, as already noted under 'Observations.' Barratt and Arnold indicate that this increase is accomplished by amitotic cell division, a process which I believe does not exist in the tissues which I have examined, either Sertoli or germinal.
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Barratt and Arnold note a diminution in size and edematous state of the testes, the clear fluid running freely upon incision of the tunic, two conditions which I found in the Osborne and ]\Iendel rats.
 +
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AVith regard to the order of cell degeneration, Regaud ('10) finds that the very young spermatocytes and the last generation of spermatogonia are very sensitive so that they are entirely destroyed. Further than this he does not analyze the order. He does note in the final stage the persistence of certain large cells long the basement membrane, which resemble the "males ovules, or better the oviform spermatogonia of the prepubertal animal." These are probably the same cells to which I have referred, and which I am inclined to interpret in the same wa5^
 +
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Barratt and Arnold ('11) indicate that the second spermatocytes are the first cells to begin degeneration, as they state that amitotic division was observed in them twenty-four hours after the application of x-rays (p. 261), while in the first spermatocytes necrosis was not observed until after the third or fourth day, necrosis of the spermatids ]K\gins after the fourth day and is marked by the ninth day, whereas the spermatogonia ceased
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DEGENERATION IN THE RAT TESTIS 107
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to be recognizable after the fourth day. These obser\ations would indicate that the spermatids were the most resistant. These chan^-es are not in the same order as T found them in the MacDowell rats, where the spermatogonia are the last to degenerate.
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The Sertoli tissue as a syncytium
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With rgeard to the Sertoli tissue, my studie- confirm Regaud's conclusion ('01) that this tissue is a syncytium. In order to satisfy myself that this is its normal state I reexamined many slides of well-fixed rats testis which I had used in my work on spermatogenesis, and studied for the first time the Sertoli nuclei and cytoplasm with great care. I found many places where the cytoplasm could be traced from one Sertoli nucleus to an adjoining one without encountering a cytoplasmic wall. In some poorly fixed material prepared while I was experimenting upon technique, I did find suggestions of a wall, but such appearances seem better interpreted as a thickening of the cytoplasm incident to the shrinking action of the fixative. This condition is quite hkely to occur when Flemming's fluid is used, if during dehydrating or infiltrating too abrupt changes are made in the strengths of the reagents.
 +
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My series of developing tubules enabled me to trace the Sertoli tissue from the very young tubules in which there is only one type of nucleus present up to the condition where all the various stages of the germ cells are present. In the young tubule a syncytium is plainly the rule. One can readil}- see when the first cytosomes are differentiated. These are early growth stages of the first spermatocytes, and are shown in figure 5 of my spermatogenesis paper (Allen, '18). As these cells continue to increase in number, they differentiate cytoplasmic walls, but I have not been able to find any Sertoli cytosome thus developed.
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The distinctive nucleolus of the Sertoli cell enables one to be certain whether, in a particular case, he is dealing with a germ or nurse cell. Consequently, determination of the stage when the Sertoli cell first differentiates is an easy matter. It does
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108 EZRA ALLEN
 +
 +
not appear until after the first spermatocytes are well developed. In fact, I did not find it until the spermatids had formed. When I made this observation I was unaware of Regaud's statement in his 1901 paper: 'La premiere apparation des noyaux de Sertol dans Tepithelium seminal a lieu, chez le Rat, au moment de la puberte, ou plus exactement au moment oii sont formes les premieres spermatozoides normaux' (p. 374, 11, 15 to 19).
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By the time this stage of growth is reached the germinative wall is closely packed with germ cells, as shown in figure 4, so that the determination of cytoplasmic walls in Sertoli cells is very difficult.
 +
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It would appear that the original syncA-tium of the young tubule persists as such, within which the germ cells lie enmeshed. In the degenerate conditions described in this paper and by Regaud, and Barratt and Arnold, and others, no new syncj'tial tissue is developed, but the Sertoli syncytium is simply revealed by the loss of the germ cells, which under normal conditions obscure it.
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The Sertoli nucleolus
 +
 +
The character of the Sertoli nucleolus needs further consideration. Previous reference has been made to the duplex nature of this body. Under normal conditions it consists of a large nearlj' spherical body close beside which is a much smaller one, also approximately spherical. For the sake of convenience, I shall refer to this latter as the paranucleolus.^ It is not wholly unique with the Sertoli nucleolus, as a similar body is to be seen in well-fixed preparations of first spermatocytes in their late growth stages. In my paper on spermatogenesis (Allen, '18), the nucleolus is sliown as a simple spherical body in figure 27. The cell from wliich this drawing was made had been fixed in Bouin's fluid, not by the fluid which gave the best fixation, B-15. Before pul)lishing the paper to which reference has just been made I did not study the nucleolus carefully in my preparations fixed with the improved fixative. Since then, in connection witli these Sertoli studies, I have discovered from this better-fixed material that its true structure is bipartite, and
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DEGENERATION IN THE RAT TESTIS 109
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unequalh^ so. Ho^ve^•e^, in the first spermatocytes the smaller body is more closely united with the larger than in the case of the Sertoli nucleolus. A similar body in connection with the nucleolus has been described by ^Miss Carothers ('13) in the germ cells of certain orthoptera. Further comparative study is needed to establish a common identity.
 +
 +
Regaud ('01 ) figures on plate 7 several Sertoli nucleoli in which the paranucleolus, as I have described it, appears distinctly. See his figures 19, 23, 38, and 39. He states that it stains blue with haematin and safranin after Tellyesniczky fixation, while the larger portion stains red. He states also that in Sertoli nucleoli fixed in bichromate acetic the nucleolus is always 'purely safranophile,' or if haematin is used it appears 'pale violet gray.' 'II est tou jours homogene et parfaitement spherique' (p. 302, 11, 31 to 34). It is thus clear that he does not regard the paranucleolus as a part of the nucleolus. He figures also one or two small bodies staining similarly to the paranucleolus which lie near the nuclear membrane, within the nucleus, such as I show in figures 15 to 17, I am inclined to think that he regards the paranucleolus as one of these which sometimes happens to lie beside the nucleolus proper. He states also, page 303, 11, 87 and 18, that the presence of two equal spherules in close contact with the nucleolus at the two extremities of one of its diameters is quite exceptional in the white rat. I have found such an arrangement of these bodies very common in the spermatogonia of the albino rat. In fact, so common that I am inclined to the opinion that perhaps it is the rule in a certain stage of their development, but more study is needed before positive statement maj' be made.
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I have not emploj-ed the bichromate acetic fixative except in one case, and it gave such poor results compared with B-15 that I did not follow it up. Therefore I cannot speak of the differential staining reaction of the larger and smaller portions of the nucleolus from my own experience. With safranin after Flemming or B-15 both nucleolus and paranucleolus stain aUke, as they do with iron alum haematoxylin. I have observed, however, in some Sertoh cells fixed with B-15 and stained with
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IIU EZRA ALLEN
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iron alum haeinatoxylin tliat the paraniiflcolus does not always stain with the same density. The associated activities of the Sertoli cells have not yet been studied full}', but there seems to be some e^^dence to indicate a connection between these and this unequal staining; reaction. At any rate, the evidence is sufficient to warrant further study under different fixatives and stains, and with \'ar3'ing physiological conditions of the rat.
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I have previously called attention to the abnormal Sertoli nucleolus in the last stages of degeneration in the Osborne and iNIendel rats, shown in my figures 11 and 13. This condition does not seem to have been noted by other workers, so far as I have read. It is shown, however, in one Sertoli cell in Regaud's figure of the x-rayed cat tubule ('10). It is not figured in any of Barratt and Arnold's Sertoli nuclei, although in other respects they duplicate those in my material.
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The interstitial tissue
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Barratt and Arnold (Tl) do not report upon interstitial tissue from their own experiments, but call attention to the work of Bergonie et Tribondeau in 1904 upon the white rat, stating that they report hj'pertrophy of this tissue a month after the last exposure to x-rays, a condition which persisted two months later.
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Physiological considerations
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I shall not do more than call attention to some matters of interest in this connection. A full discussion would be premature, under all the circumstances. There would seem to be a similar physiological condition induced by such widel}' different agents as x-raj^s and the lack of a plentiful supply of watersoluble vit amine in the diet. This similarity is manifested in both the degeneration of the sex cells and the hypertrophy of the interstitial tissue. In the case of the Osborne and Mendel rats the hypf)physis was smaller than normal (from measurements made by Donaldson on five rats from this same series). Regaud ('01 j reports degeneration in llic distal portions of the tubules, but gives no cause for it. The MacDowell rats, both alcoholics
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DEGENEEATION IN THE RAT TESTIS 111
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and four out of the non-alcoholics, show degeneration to greater or less extent; all of the alcoholics more than the others. All ten of these rats had been starved briefly (from seventy to eighty-fi.ve days of age), but all had lived for more than two months after that. Aside from this apparently shght detrimental influence, we know of no cause for the degeneration in the non-alcoholics. If one were present, it would appear that the alcohol aggravated its deleterious effect upon the germ cells.
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That this degeneration is not an old-age phenomenon is proved conclusively by the conditions found in many rats of the Wistar colony older than any of the MacDowell lot, and one of about six years of age. In none of these is this type of degeneration to be seen. I have prepared a series of testes of rats from the colony at various ages — standards, hybrids, and inbreds — and none of them indicate that there might be an individual variation along this line.
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It would appear, therefore, that experiments upon comparative diets would throw light upon the physiological problems raised by the conditions discussed in this paper. Examination of all the organs, especially those of the endocrine system, would be desirable in the case of such animals.
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SUMMARY
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1. Reduction in the quantity of water-soluble vitamine in the diet of rats results in total degeneration of all the germ cells, but does not interfere with growth and development in other respects. The Sertoli tissue persists.
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2. In the male this atrophy of germ cells is accompanied by hypertrophy of the interstitial tissue.
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3. The type of degeneration in the male germ cells is similar to that produced by x-ray treatment of the testes directly.
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4. A similar degeneration of male germ cells has been observed in a group of rats, part of which were subjected to prolonged alcoholization. The degeneration was found to a less extent in all but one of their five brothers not alcoholized. In this group hypertrophy of interstitial tissue was not observed.
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112 EZRA ALLEN
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5. Examination of this degenerated tissue and more careful stud}' of normal, well-fixed tissue confirms Regaud's conclusion that the Sertoli tissue is a syncytium.
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6. The nucleolus of the Sertoli cell under these degenerated conditions appears to be an equally bipartite, instead of as normally an unequally bipartite body.
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7. The interstitial tissue is much increased in quantity in the rats fed upon a reduced water-soluble vitamine.
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LITERATURE CITED
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Ali-ex, Ezra 1916 Studies on cell division in the albino rat (Mus norvegicus var. alba). II. Experiments on technique, with description of a method for demonstrating the cytological details of dividing cells in brain and testis. Anat. Rec, vol. 10.
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1918 Studies on cell division in the albino rat (Mus norvegicus albinus)* III. Spermatogenesis: The origin of the first spermatocytes and the organization of the chromosomes, including the accessory. Jour. ^lorph., vol. 31.
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B.\RR.\TT. W., .\ND Arnold, G. 1911 Cell changes in the testis due to x-rays. Arch, fiir Zellforschung, vol. 7.
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Bergoxi6 et Tribonde.\u 1904 Action des rayons x sur le testicule du rat blanc. C R. Soc. de. Biol., T. 2.
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Carothers, E. Eleanor 1913 The Mendelian ratio in relation to certain orthopteran chromoiomes. ' Jour. Morph , vol. 24.
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Colwell, H. a., and Rtjss, S. 1915 Radium, x-rays and the living cell. London.
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MacDowell, E. C, and Vicari, E. M. 1917 Growth and fecundity of alcoholized rats. Proc. Nat. Acad. Sciences, vol. 3, no. 9
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Regaud, Cl. 1901 fitudes sur la structure des tubes seminif^res et sur la spermatog6nese chez les Mammiferes. Arch. d'Anat. micr., T. 4. 1910 Particularite d'actions des rayons de Rontgen sur I'dpithllium seminal du chat. C R. Soc de Biol,, vol. G8 (OJnd year).
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PLATES
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The photomicrographs were made by the author with combinations of lenses suitable for the magnification desired, figures 11 to 14 with oil immersion. Figures 1 to 6 are reproduced at the original size. Figures 7 to 14 are reduced one-third from photographs which were made by enlarging the original negatives three times by projection. The drawings were made by tracing the outlines on the backs of photographs, transferring these to the drawing-paper by a sheet of carbon, and filling in the details with lithographic pencil.
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The sections were cut at 7)U or lO/x and strained with iron haematoxylin and acid fuchsin. All are froiii the Mendel and Osborne rats except figures 7 and 10, which are from the MacDowell series, and figures 14 to 17, which are from an adult normal rat from the Wistar colon v.
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113
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PLATE 1
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EXPLANATION Or FIGURES
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1 and 2 From nos. 3554 and 3G10, showing the difference in appearance between the two. Limited portions of these are enlarged in figures 8 and 9. The exceptional!}' large quantity of interstitial tissue is well shown in figure 1. This rat was injected with the fixing fluid, a process which preserves more nearly the normal relationship between tubule and interstitial tissue and holds the bloodvessels distended. X 30.
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3 From no. 3756. Three adjoining tubules showing unequal stages of degeneration, A, B, and C. X 150.
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4, 5 and 6 are enlarged views of the tubules shown in figure 3. X 300.
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114
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DEGEXERATIOX IN THE RAT TESTIS
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EZRA ALLEN
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PLATE 1
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115
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PLATE 2
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EXPLANATIOX OF fIGURES
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7 and 10 From MacDowell rats nos. 704 and 764. showing the difference in degree of degeneration: both alcoholics. C, cavities. These arc very distinct in figure 7, while almost unnoticeable in figure 10. The germinal epithelium is practicallj' normal in figure 10, while in figure 7 it is nearly as abnormal as iu figures S and 9. X 60.
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8 and 10 Enlarged views of portions of figures 1 and 2, showing details of the germinal epithelium a little better. X GO.
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11. 12 and 13 These figures .show the wrinkled nuclie and the characteristic diploid nucleoli of the Sertoli tissue. Figure 11 fairly represents the Sertoli syncytial cytoplasm. A grooved iiucleu.s is shown in the extreme right; two others near the lower center. X loOO.
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14 Small portion of normal epithelial wall of tubule, showing at S. C. the Sertoli nucleus. At the right of this nucleus the Sertoli cytoplasm extends to the spermatozoan heads at the extreme right, passing between first two spermatocyte cells in earlj' prophase and tA\o spermatids, respectively, as one traces it from the nucleolus to the spermatozoan heads. X 1500.
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15, 16 and 17 Three nuclei of Sertoli cells, showing the paranucleolus in each .and the small bodies which stain similarly but lie near the nuclear membrane Figure 15 is the same nucleus as is shown in figure 11. X 1500.
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116
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DEGEXERATIOX IN THE RAT TESTI?
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EZRA ALLEX
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PI-ATE 2
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9#u*«
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>^' Vi' .
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S.C.I
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1^%
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>
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=?5b:=^
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117
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«^A
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RALPH EDWARD SHELDON^
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1883-1918
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In Memoriam
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ROBERT RETZER
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By the death of Ralph Edward Sheldon the University of Pittsburgh lost one of its most constructive and conscientious professors, the American Association of Anatomists a member who ranked first among the present generation, and his colleagues a loyal and true companion. In the University he was a counsellor whose opinions were valued by his seniors, and as a teacher he brought out the best qualities in his students. His investigations in the field of neurologj^ gained him a national reputation. We mourn his departure the more because he left us so suddenly with his promising life's work but haK completed.
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Doctor Sheldon was born at Lisle, New York, on IMarch 28, 1883, the son of Herbert Clayton Sheldon and Rosaha Reed Sheldon, who both show a long line of New England ancestry that can be traced on one side to John Alden. As a boy he was exceedingly fond of outdoor sports, and kept up this interest until he went to Harvard. He then became so absorbed in work that he gave it up, but promised himseK a renewal of these activities when he had completed the book.
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After attending the public schools, he entered Cornell L'niversity in the College of Forestry, but as this College was discontinued after the first j'ear, he took the regular Arts course. He continued his interests in this field, as is testified by the fact that during the summers of 1902 and 1903 he was assistant in the L'nited States Forest Service. Voluminous notes taken at these expeditions together with numerous books and reprints also bear testimony to this interest. This probably would have become an avocation had he found any time to spare. Three
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^ An address, in memory of Ralph Edward Sheldon, presented at the thirtyfifth session of the American Association of Anatomists, convened at the University of Pittsburgh, April 17, 18, and 19, 1919.
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119
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THB ANATOMICAI. RECOKD, VOL. 16, NO. 3
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120 RALPH EDWARD SHELDON
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years after matriculation in 1904 he received the A.B. degree and a scholarship in Neurology which led to a Master's degree m 1905. He then was rewarded the Goldwin Smith Fellowship in Neurology, which he held during the year 1905-06. He was known as a hard worker, and throughout his college career he earned monej^ to pay for his education. He took most careful notes in all his studies, which were of the most varied kind, including Latin, Greek, French, German, survejdng, botany, chemistry, and phj^sics. In later life he acquired a reading knowledge of Spanish, Italian, and a little Dutch.
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In the sunmiers of 1904 and 1905 he was Assistant in Zoology at Cornell. WTiile at Cornell he worked for Professor Wilder and became interested in Neurology. It is unquestionable that this association exercised the greatest influence in his career. Having built a small summer home in Ithaca, he went back to work at Cornell University many summers. From 1906 to 1907 he worked under an Edward Austen Fellowship under Professors Alark, Parker, and Castle at Harvard and received the S.M. degree. He then received a fellowship in the University of Chicago, but a vacancy occurring he was appointed Assistant in Anatomy. After one year he received a Ph.D. degree under the direction of Professor Herrick, with the thesis, The Olfactory Tracts and Nerve Centers in Teleosts." He was appointed Associate in Anatomy in 1909, but feeling the necessity of a salary that was adequate to meet the needs of a growing family he accepted an offer of Professor Cohoe to become Assistant Professor of Anatomy at the University of Pittsburgh. After three years he was appointed Associate Professor and in 1914 Professor and Head of the Department.
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At times he was discouraged because he soon realized that it was almost impossible to combine research work with the many duties that fell upon his shoulders, but he nevertheless not only kept up his scietific interest, but managed to write a creditable number of scientific papers. Had he not undertaken to write a textbook on Neurology the anatomical world would have been enriched considerably by many more contributions.
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He was a Fellow of the American Association for the Advancement of Science and a member of the American Medical
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IN MEMORIAM 121
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Association, American Association of Anatomists, American Physiological Society, American Society of Zoologists, American Society of Xatmralists, Anatomische Gesellschaft, Society of Biological Research of the University of Pittsbm-gh, Allegheny Comity ^Medical Society, Pittsburgh Nem^ological Society, and of the Gamma Alpha, Phi Rho Sigma, and Sigma Xi Fraternities. He was very active in the Cornell Almnni Association and for years was secretary of the scholarship committee of Western Pennsylvania. He was also a member of the Harvard and of the Chicago Alumni Associations.
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At the last meetmg of this Association, Doctor Sheldon extended the invitation of this department for the next meeting. He was keen to show what this department had accomplished in the few years since he had taken hold of it. It should be remembered that when he came here less than ten years ago this building had not been built. The school was in the process of reorganization and presented all the crudeness which was so common in all of our proprietary medical schools at that time.
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The physical equipment of the Department of Anatomy of the University of Pittsburgh Medical School as you see it to-day is essentially the work of Doctor Sheldon. ^Tien one reviews his brief career before Doctor Sheldon came to this institution, one cannot but marvel at his remarkable ability to combine what he found best in other institutions, organize, equip, and administer a department in a manner that would have been a credit to a man of twice the amount of Doctor Sheldon's experience. While this accomplishment might have been attained by many a man whom we are wont to speak of as having an executive ability, it is most remarkable that through it all Doctor Sheldon never allowed hunself to be so overwhehned by the multifarious duties that he could not continue the prosecution of research. It is true that we find in looking over his publications that there are a number of papers that deal strictly with matters of laboratory equipment, yet I have found among his documents innumerable notes on scientific observations he had made that needed but little more work in order to put them before the public. Here we must not forget that he was a young man and had standards
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122 RALPH EDWARD SHELDON
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of perfection which were difficult to attain. With years we gradually learn that careful observations, although limited in scope, are in themselves valuable to others besides ourselves and merit publication. As I say when we scrutinize his Ust of publications, we may doubt whether he may not have fallen by the wayside as is the fate of so many men of promise who undertake administrative duties. One needs but look carefully at some of his chapters in his text-book, however, to come to a very different conclusion. Observation of facts and phenomena is but the framework — the body — of Science. It is the elucidation and the correlation of these observations that give Science life. Sheldon not only observed keenly, but he analyzed and criticised keenly. The major part of his book is not a paraphrase of the writings of other neurologists, but a critical analysis of the most recent work on the subject.
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He took a remarkabl} keen interest in the students' welfare and progress. Although in the last years he gave but one course, that of neurology, he always inquired of his staff, how each student was progressing, and at least once a year he interviewed each student personally, giving a word of cheer or encouragement whenever he could, but showed no leniency in meting out punishment to offenders. In this connection I challenge anyone who will say that there is any medical school where the scholarship and the personal fitness of its students are more carefully scrutinized and where students who do not maintain a given standard are either forced to withdraw from the school or repeat the entire year. We owe this primarily to Doctor Sheldon. It was he who set the standards of attainment for the first-j^ear students; it was he who brought the names of the delinquents before the executive authorities, and it was he who always unflinchingly stood for the best. He may have appeared to some as a heartless judge, but yet beneath that sternness was a melting heart. He expected the student to do well the work allotted to each course. If he failed to do so, it meant repetition of the course, and this frequently entailed the repetition of the whole year. This seemed to him such a hardship that he voluntarily without any financial reward gave summer courses for those
 +
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IN MEMOKIAM 123
 +
 +
students who were unable to attend regular summer schools in order to enable them to continue with their classes.
 +
 +
"\Mien war broke out Doctor Sheldon, Uke all true patriots, wanted to tender his services. He was urged by ^Major Bagley to apply for a commission. He was torn between two duties, and chose the harder one — he stayed at home. He, nevertheless, offered the ser\aces of this department to the Council of National Defense and began some very important work on staining methods for formalin-fixed material. The first report was sent to Washington a few weeks before his death. The methods he devised were then used in several laboratories in the neuropathological ser\'ice.
 +
 +
We meet here in the department which at every turn bespeaks of his acti^dties. In the dissecting-room the tables, book racks, museum cases, cadaver tanks, all were designed in every detail by him. In the histological laboratory the desks with the interchangeable units of drawers, slide holders, and reagent racks, in the private rooms the slide and stock cases were built according to his specifications. A case full of charts, nearly all of which were drawn under his direction, give further evidence of his zealous attempts to serve the student and the medical school. The anatomical hbrary was built up by him, and considering the short time he was at the helm, the war conditions, and the not too ample funds, it shows better than anything else how he had built for permanence. The library is not filled with antiquated text-books, but with most of the current anatomical periodicals. What cannot be seen but is nevertheless felt by those who have been associated with him is the highly scientific and moral atmosphere which he had created in the nine years he was a teacher in this institution.
 +
 +
He was a most indefatigable worker and a most meticulously careful man, and as is so often the case with men of this type, he expected everyone else to do as much as he did. His employees dared not shirk their tasks. Every day he quickly passed through all the rooms of the department and noted everything that was done or undone. It should not be judged from this that he attempted to run the department single
 +
 +
 +
124 RALPH EDWARD SHELDON
 +
 +
handed. It was his aim to train the members of his staff to do the right kind of work and then give them responsibihties. He conferred and directed but allowed his assistants to work out the details. The result was that these men acquired an independence of thought and action as is rarely found in an institution that is guided by a youthful hand.
 +
 +
His activities did not cease with the work he found to do in his department. His unbounded enthusiasm and determination caused his colleagues to throw many more burdens on his shoulders. One has but to look over the documentary file of this department to reaUze that not one single phase of medical school and university administration had escaped his personal attention. Elaborate tabulations of curricula, schedules, budgets, staffs, and equipment of every prominent medical school in the country were orderly filed. Though the youngest professor, he was chosen the representative at large of the medical school to sit in the council of the University. Committee meetings upon committee meetings consumed his energy, of which he seemed to have an absolutely unlimited amount. The reason he devoted so much time to these activities is well expressed in a letter written on December 1, 1915.
 +
 +
It seems to me that every individual in the service of the University should be made to feel that the interests of the University must always be paramount to those of the individual. A department for instance is not the personal possession of its chief. He is given certain rights, privileges and facilities in order that he may use these for the interests of his school and the University as a whole. To the extent which he fails to do this, he is not living up to his obligations to the institution. I feel, of course, that a considerable leeway must be given in the interpretation of this in order that full advantage may be taken of individual initiative, and that, therefore, it is not possible to lay down hard and fast rules regarding the conduct of individual departments. If it could, however, be indicated to ever}^ member of the teaching staff that loyaltj' to the department, the school and University would be an important factor in evaluating his work, and if the individual could feel that all were on an equal footing in this regard, I believe it would do more than anything else to estal)lish, in the institution, a spirit of affection and loyalty. In this evaluation a wide acquaintance of the work of all departments of the University and high ideals of attainment are necessary in order that work of individuals and departments
 +
 +
 +
 +
IN MEMORIAM 125
 +
 +
along widely divergent lines shall be fully appreciated and that substantial work for the benefit of the institution receive due credit as compared with that which happens to receive publicity.
 +
 +
As pre\'iously stated, he was intensely interested in scientific work, and his published papers show^ that he was as capable a scientist as he was an administrator. In his paper on The Nervus Terminalis in the Carp," he gave the first account of this nerve in the teleosts. "The Olfactory Tracts and Centers in Teleosts" is his magnum opus of scientific research. It represents the most detailed and accurate analysis by an anatomical method of the functional localization of tracts and centers of any vertebrate hitherto described. He carried the work to the last refinement permitted by a combination of all available strictly anatomical methods, and the w^ork is a model of its kind.
 +
 +
It was only after his death that I learned that Doctor Sheldon was very much interested in Chemistry. It is therefore not surprising that the interest in this science should have led him to apply it to neurology. In The Reactions of the Dogfish to Chemical Stimuli" he showed that the skin of fishes is exceedingly sensitive to some chemicals, even more so in some cases than the taste-buds. In "The Sense of Smell in Selachians" and "The Sense of SmeU in Teleosts" he intended to test physiologically the anatomical work of his doctor's thesis. These five papers represent an ideal of combined anatomical and physiological work on a definite program such as has rarely been attained by any investigator.
 +
 +
"The Phylogeny of the Facial Xerve and Chorda TjTapani" is a valuable summary illustrating the value of comparative study in sohdng vexed problems of mammahan anatomy. Phylogenetic history, experimental physiology, and pathological anatomy are brought to bear on the problem of human peripheral conduction ' paths bringing about noteworthj- results in clarifying practical problems of siu'gei;y. He summarized in "The Paraffine-Weigert ^Methods for the Staining of Nervous Tissue, with Some Xew ^Modifications" his own and many others' extensive experience in the diflBcult problem of getting the most possible out of the Weigert method in the study of both human
 +
 +
 +
 +
126 RALPH EDWARD SHELDON
 +
 +
and comparative brains. It is one of the most helpful contributions to technique in the literature.
 +
 +
f ^^'hen he was but twenty-six years old he projected a text-book on Neurology. This undertaking was his life of the last two years and it was his death. The book was practically written with 950 pages of manuscript six years ago. Being inexperienced, he thought it a comparatively easy matter to have the illustrations made and the manuscript set to type. Before long he was sadly disillusioned.
 +
 +
\^'hen I came to this department a little over two years ago I was asked to look over a few chapters of the book. I was amazed to find that the book which I had expected to use for my classes the previous year had not progressed any farther, but it did not take me long to find the cause of this delay. It was not teaching, it was not administrative work that was the cause of the delay, but his endeavors to do the impossible — write a perfect text-book. His publishers rightly urged and urged. Letters, telegrams, and representatives called for haste. He finally realized that perfection was not attainable and more rapid progress was made. He was relieved of most of his teaching duties, and then it was book from early morning to late at night. His almost indecipherable handwriting made it difficult for his stenographers, and to facilitate matters he used the dictating machine.
 +
 +
This is not the place to review the book. It represents the first attempt to present in a text-book the subject of Neurology from a functional point of view. It is intended to give the medical student a broad conception of the fundamental principles that underlie the structure and function of the nervous system, but at the same time pointing out the paths for future investigations. The reason he undertook this work may be best stated in his own words found in the preface written many years ago.
 +
 +
To the older anatomists the nervous system was only an anatomical structure, to be dissected out and studied in relation to the other organ systems, such as the l)ones, blood-vessels, muscles, etc. This attitude of mind led to the development of a school of neurologists, both human and comparative, who devoted themselves to the study of the gross
 +
 +
 +
 +
IN MEMORIAM 127
 +
 +
morpholog}'- of the brain and peripheral nervous system in the most minute detail, identifying and comparing every depression, protuberance, and membrane and their relations to the surrounding tissues of a different kind. Although his interests are different, the worker of to-day, with a wealth of technical methods at his disposal, must always look with amazement and admiration at the results which these men secured with the crudest of methods.
 +
 +
At present there is no treatise avail9,ble, which, in addition to the gi'oss relations, will give to the student of anatomy, neurology, medicine or to practicing physicians, a complete presentation of the functional relations of the nervous sj^stem. This book represents an endeavor to fill this gap and to present in an adequate fashion for such workers the gross and microscopic anatomy of the nervous system with all the more important functional relations.
 +
 +
I cannot help but speak from the very depth of my emotions. The two years that I w^as associated wdth him I treasure as two of my most valuable ones. There was no barrier between us and I felt I had his utmost confidence as he had mine. We had similar ideals and it was a distinct pleasure to be able to W'Ork harmoniously by his side. Not once during these years did w^e part in an argument or discussion but that I felt a greater admiration for his personality. The sternness which he felt he had to assume on account of his youth W'Ould melt in a smile that made you feel happy in his presence. He seemed to fairly radiate good-will and energy.
 +
 +
I am glad that a month before his death I had coerced him to take an auto trip wdth me through Maryland. We both were boys again. Oblivious of everything that might burden the heart of a man we were for tw^o days as care-free as the birds that flitted about. He vow^ed that he never had had such a good time and promised that before the summer was over he would take his family over the same trip. A month later and his bright career came to an end. On Sunday he w^orked to get off some drawings to the publishers. On ]\londay he felt 'grippy' and thought he would rest up a bit. On Tuesday morning, July 9, he got up and thinking that it might dispel his lassitude he took a hot bath. Allien he stepped out of the tub, weakness w^as manifest in one foot. Before the hour was over both feet w^ere paralyzed. The paralysis rapidh' crept upward, and by midnight his spirit had departed. It is curious irony of fate that Dr. Sheldon should have succumbed to a nervous dis
 +
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128 RALPH EDWARD SHELDON
 +
 +
ease, Landry's acute ascending paralysis, the nature of which we understand so little. It is probable that he thought the paralysis a transient one. He was hopeful to the end.
 +
 +
The influence Dr. Sheldon exerted during his brief career will live a long time. His scientific work has placed him among those that have given substantial contributions to the. advancement of knowledge. The influence he exerted as an educator will long be felt by his students and by his students' students. He founded a department which it is hoped will ever reflect credit to his name. It is also hoped that, realizing the debt the University and the anatomical world owes him, a way will be found to bring before the world the book which will always stand a monument to industry.
 +
 +
PUBLICATIONS
 +
 +
The participation of medullated fiber? in the innervation of the olfactory mucous
 +
 +
membrane of fishes. Science, vol. 27 pp. 915-916. 1908. An analysis of the olfactory paths and centers in fishes. Proc. Assn. Amer.
 +
 +
Anat., Anat. Rec, vol. 2, no. 3, pp. 108-109. 1908. The nervus terminalis in teleosts. Proc. Assn. Amer. Anat., Anat. Rec, vol. 3,
 +
 +
no. 4, pp. 257-259. 1909. The nervus terminalis in the carp. Jour. Comp. Neur. and Psychol., vol. 19,
 +
 +
no. 2, pp. 191-201, figs. 1-7. 1909. The reactions of the dogfish to chemical stimuli. Jour. Comp. Neur. and Psychol., vol. 19, no. 3, pp. 273-311, figs. 1-3. 1909. The phylogeny of the facial nerve and chorda tympani. Anat. Rec, vol. 3, no.
 +
 +
12, pp. 593-617, figs. 1-6. 1909. The sense of smell in selachians. Jour. Exp. Zool., vol. 10, no. 1, pp. 51-62.
 +
 +
1911. Some new laboratory furnishings. Anat. Rec, vol. 5, no. 10, pp. 483-490, pis.
 +
 +
1^. 1911. The olfactory tracts and centers in teleosts. Jour. Comp. Neur., vol. 22, no. 3,
 +
 +
June, pp. 177-255, pis. 1-42. 1912. The sense of smell in fishes. With G. H. Barker. Bulletin of the U. S. Bureau
 +
 +
of Fisheries. Vol. 32, 1912, Document No. 775, May 3, 1913, pp.
 +
 +
35-46. Some new dissecting-room furnishings. Anat. Rec, vol. 7, no. 10, pp.
 +
 +
369-370. 1913. ParaflBne-Weigert methods for the staining of nervous tissue, with some new
 +
 +
modifications. Folia Neuro-Biologica, Bd. 8, Nr. 1, S, 1-28. 1914. Some new receptacles for cadavers and gross preparations. Anat. Rec, vol. 9,
 +
 +
no. 4, pp. 323-327, figs. 1-8. 1915.
 +
 +
 +
 +
PROCEEDINGS OF THE AMERICAN ASSOCIATION OF ANATOMISTS
 +
 +
THIRTY-FIFTH SESSION
 +
 +
Medical School of the University of Pittsburgh; Pittsburgh,
 +
 +
Pennsylvania
 +
 +
April 17, 18 and 19, 1919 Thursday, April 17, 9.30 a.m.
 +
 +
The thirty-fifth session of the American Association of Anatomists was called to order by President Robert R. Bensley, who appointed the following committees:
 +
 +
Committee on Nominations for 1919: Professor J. Plaj^fair McMurrich, Chairman; and Professors George S. Huntington and Florence R. Sabin.
 +
 +
Auditing Committee: Professor Eliot R. Clark, Chairman; and Professor Frederic T. Lewis.
 +
 +
The morning session was devoted to the presentation of scientific papers followed by a paper in memory of the late Professor R. E. Sheldon, presented by Professor Robert Retzer. Following this, the final feature of the morning programme was an address by the President of the Association, Professor Bensley on "Anatomy, a Science or a Curriculum?"
 +
 +
Friday, 11.30 a.m. Association Business Meeting, President Robert R. Bensley, Presiding.
 +
 +
The Secretary reported that the minutes of the Thirty-Fifth Session were printed in full in The Anatomical Record, volume 14, number 1, pages 19 to 23, and read the minutes as printed. On motion, seconded and carried, the minutes of the Thirtj'fourth Session were approved bj the Association as printed in The Anatomical Record.
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Professor E. R. Clark reported for the Auditing Committee
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129
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130 AMERICAN ASSOCIATION OF ANATOMISTS
 +
 +
as follows: The undersigned Auditing Committee has examined the accounts of Doctor Charles R. Stockard, Secretary-Treasurer of the Association of Anatomists and finds the same to be correct with proper vouchers for expenditures and bank balance on January 8th, 1919, of $211.59.
 +
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(Signed) Eliot R. Clark,
 +
 +
Frederic T. Lewis.
 +
 +
The Treasurer made the following report for the j^ear 1918:
 +
 +
Balance on hand December 19, 1917, when accounts were last
 +
 +
audited $303.83
 +
 +
Receipts from dues 1918 2391.86
 +
 +
Total deposits S2695.69
 +
 +
Expenditure for 1918:
 +
 +
Expenses Secretary-Treasurer. Minneapolis Meeting $132.91
 +
 +
Postage and Telegrams 48. 12
 +
 +
Printing and Stationery 45.24
 +
 +
Collection and exchange on drafts 1 . 73
 +
 +
Stenography, tj-pewriting 45.60
 +
 +
One check returned and debited 7.00
 +
 +
Wistar Institute, subscriptions to Journal of Anatomy,
 +
 +
Anatomical Record, etc 2203.50
 +
 +
Total expenditures 2484. 10
 +
 +
Balance on hand $ 211 . 59
 +
 +
Balance on hand, deposited in the name of the American Association of Anatomists in the Corn Exchange Bank, New York City.
 +
 +
On motion the report of the Auditing Committee and the Treasurer were accepted and adopted.
 +
 +
The Committee on Nominations through its Chairman, Professor Thomas G. Lee, placed before the Association the following names: For members of the Executive Committee, term expiring 1922, Professors C. W. M. Poynter, and H. M. Evans.
 +
 +
On motion the Secretary was instructed to cast a ballot for the election of the above named.
 +
 +
The Secretary presented the following names recommended by the Executive Committee for election to membership in the American Association of Anatomists :
 +
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PROCEEDINGS 131
 +
 +
Baker, Wilmer, M.D., Assistant Professor of Anatomy, University of Virginia,
 +
 +
University, Virginia. Beck, Claude S., A.B., Medical Student, Johns Hopkins Medical School, Baltimore, Maryland. Davis, Carl L., M.D, Professor of Anatomy, George Washington University,
 +
 +
Washington, D. C. Dawsox, Aldex B., A.m., Ph.D., Assistant Professor of Microscopical Anatomy,
 +
 +
Loyola University Medical School, 706 S. Lincoln St., Chicago, III. Ford, Fraxcis C, A.B., M.D., Professor of Anatomy, Hahnemann Medical
 +
 +
College and Hospital of Chicago, 2811 Cottage Grove Avenue, Chicago, HI. Frassetto, Fabio, M.D., Ph.D., Director Anthropological Institute, University
 +
 +
of Bologna, Bologna, Italy. (Present address Royal Italian Embassy, Washington, D. C.) Frexch, H. E., M.S., M.D., Professor of Anatomy and Dean of the School of
 +
 +
Medicine, University of North Dakota, Grand Forks, North Dakota. Gouu), Harley Nathax, A.M., Ph.D., Assistant Professor of Anatomy, School
 +
 +
of Medicine, University of Pittsburgh, Pittsburgh, Pa. HowDEX, Robert, M.A., M.B., CM., D.Sc, Professor of Anatomy, University
 +
 +
of Durham, 14 Burdon Terrace, Newcastle-upon-Tyne , England. Howlaxd, Rcth B., Ph.B., Ph.M., Professor of Biologj', Sweet Briar College,
 +
 +
Sweet Briar, Virginia. Job, Thesle T., M.S., Ph.D., Assistant Professor of Anatomy, Loyola University
 +
 +
School of Medicine, 706 S. Lincoln St., Chicago, III. Krause, Allex Kramer, A.M., M.D., Associate Professor of Medicine, Johns
 +
 +
Hopkins University, Johns Hopkins Hospital, Baltimore, Md. Larsell, Ol.af, Ph.jj., Assistant Professor of Anatomy, University of Wisconsin,
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 +
Madison, Wisconsin. MacCreadt, Patjl B., B.S., Medical Student, Johns Hopkins Medical School,
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 +
Baltimore, Md. McIxTOSH, William, A.B., A.M., Student of Medicine, Johros Hopkirts Medical
 +
 +
School, Baltimore, Maryland. Marshall, Matthew, B.S., Assistant in Anatomy, School of Medicine, University
 +
 +
of Pittsburgh, Pittsburgh, Pa. Matsumoto, Takasabure, M.D., Professor of Anatomy and Neurology, Chiba
 +
 +
Medical College, Chiba, Japan. Me.u), Harold Tupper, B.A., M.S., Associate Professor of Zoology, Tulane
 +
 +
University, New Orleans, La. XoBACK, GrsTAVE J., B.S., Instructor in Anatomy, Anatomical Institute, University of Minnesota, Minneapolis, Minn. Pracher, Johx, M.D., Assistant Professor of Anatomy, Georgetown Medical
 +
 +
School, Washington, D. C. Roys, Charles K., A.B., M.D., Assistant in Anatomy, Anatomical Institute,
 +
 +
University of Minnesota, Minneapolis, Minn. Shaxer, Ralph Faust, Ph.B., Teaching Fellow, Department of Anatomy, Harvard
 +
 +
Medical School, Boston, Mass. «<
 +
 +
Shimidzit, Yoshitaka, M.D., Professor of Gynecologj', Aichi Medical College,
 +
 +
Nagoya, Japan.
 +
 +
 +
 +
132 AJMERICAN ASSOCIATION OF ANATOMISTS
 +
 +
Stewart, Fred Waldorf, A.B., Instructor in Anatomy, Cornell University Medical College, Ithaca, N, Y.
 +
 +
SwETT, Francis Huntington, A.M., Medical Department, U. S. Army, Norway, Maine .
 +
 +
Takenouchi, Matsuziro, M.D., Assistant Professor of Bacteriology and Immunology, Medical College, Imperial University oj Tokio, Tokio, Japan.
 +
 +
Vance, Harry Wellington, A.B., Medical Student, Johns Hopkins Medical School, Baltimore, Md.
 +
 +
Wegeforth, Paul, A.B., M.D., Captain M. C, U. S. A., 306 Grangu Bldg., San Diego, Calif.
 +
 +
On motion the Secretary was instructed to cast a ballot for all the candidates proposed by the Executive Committee. Carried.
 +
 +
The special committee on the nomenclature of the sympathetic nervous system reported progress and was retained.
 +
 +
The Secretarj^ read to the Association communications from the Anatomical Society of Great Britain and Ireland regarding a revision of the present anatomical nomenclature and requesting that the American Association of Anatomists appoint a committee with power to take up the matter of collaboration in revising the existing anatomical nomenclatures.
 +
 +
The question of adjustment and modification of nomenclature was extensively discussed by Professors Huntington, IVIcMurrich, Bensley, Terry, Senior, Todd and Jackson. It was finall}^ moved by Professor B. D. Myers, seconded and carried that the Chair appoint a committee to draft resolutions regarding the revision of anatomical nomenclature; and that such a committee be instructed to report back to the Association on the last day of the present session.
 +
 +
The Chair named on this Committee Professor J. Playfair Mc^Iurrich, Chairman, and Professors George S. Huntington and H. H. Donaldson.
 +
 +
Through the Secretary the Executive Committee requested the Association to instruct them regarding the proper interpretation of the clause from the constitution relating to the election of new members; Article V, Section 1.
 +
 +
The discussion was based on the proper administration of the clause "Candidates for membership must be persons engaged in the investigation of Anatomical or cognate sciences." The
 +
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 +
PROCEEDINGS 133
 +
 +
principles involved in this question were discussed by Professors W. H. Lewis, Evans, Retzer, Enunel, McMurrich, Huntington, Bardeen and Donaldson.
 +
 +
Finally it was moved by Professor Bardeen, seconded and carried :
 +
 +
That it is the sense of the members of this Association that the Executive Committee should as a rule interpret the existing statutes on requirement for membership to mean that the candidate shall have published one or more contributions to anatomy or cognate sciences.
 +
 +
The Secretary then presented for the consideration of the Association the two circular letters recently mailed to the members in reference to the future arrangements for publication of the American Journal of Anatomy and The Anatomical Record. The first of these circular letters was drawn by the Trustees of the Minot Memorial Fund in whom is vested the title of the two above named journals.
 +
 +
The Trustees presented two proposals; in the first place to transfer the title of the two journals to the American Association of Anatomists, and to allow the Association absolute control and all financial responsibility for the organization and conduct of the two journals. In the second plan the title of the two publications was to be transferred to the Wistar Institute of Anatomy and Biology, and the journals were to be conducted under a Board of Control consisting of the trustees of the Minot Memorial Fund and members elected by the American Association of Anatomists.
 +
 +
In connection with these proposals from the trustees of the Minot Memorial Fund the Director of the Wistar Institute, Dr. M. J. Greenman, had drawn the second circular letter to show in general the growth and financial condition of the journals under the present arrangements for publication by the Wistar Institute.
 +
 +
The great importance of the proposals presented in these circular letters was appreciated by the Association and very fully discussed by Director Greenman and Professors Huntington, Stockard, Coghill, McMurrich, Knower, and Bardeen.
 +
 +
 +
 +
134 AMERICAN ASSOCIATION OF ANATOMISTS
 +
 +
Finally it was moved by Professor Bardeen, seconded by Professor Jackson and carried.
 +
 +
That, whereas the members of this Association are themselves primarily concerned witli the publication and support of anatomical journals in this country; and, whereas information concerning the past, present and possilile future, status of the existing journals in this field, the American Joui'nal of Anatomy and the Anatomical Record is incomplete.
 +
 +
Be it resolved that the President of the Association be requested to appoint a committee of three to report at the next annual meeting of the Association possible plans for the future publication of these journals together with such other recommendations as may seem desirable as a result of their investigation.
 +
 +
The President appointed such an investigation committee consisting of Professor George L. Streeter, Chairman; and Professors Charles R. Bardeen and Clarence M. Jackson.
 +
 +
On motion the business session adjourned.
 +
 +
Saturday, April 19. A Business Session Followed the ]\IoRNiNG Scientific Session.
 +
 +
It was announced by the Secretary that the Executive Committee had voted to hold the next annual meeting of the Association in Washington, D. C, during the week preceding Easter Sunday, 1920.
 +
 +
The committee appointed at the previous business session to draft resolutions regarding the revision of anatomical nomenclature reported through its Chairman, Professor J. P. McMurrich, as follows:
 +
 +
Whereas this Association is fully persuaded that both from the standpoints of instruction and investigation a uniform and definite terminology is essential for the progress of Anatomy and whereas the Basal Nomenclature furnishes a basis for such a terminology and has been emplo3^ed very generally in the Medical Schools of this country and in the text-books used by our students.
 +
 +
Resolved that this Association considers it inadvisable to abandon the Basal Anatomical Nomenclature and recommends that a committee be appointed from the Association to confer with the Anatomical Society of Great Britain and Ireland with a view to cooperating in a revision of that nomenclature.
 +
 +
The report was accepted, and it was moved and carried that President Bensley appoint such a committee with himself as Chairman.
 +
 +
 +
 +
PROCEEDINGS 135
 +
 +
The following resolution was introduced by Professor F. T. Lewis and seconded by Professor Bardeen in recognition of the valuable aid and stimulation that has been rendered to science in this country through the publications edited by Professor J. McKeen Cattell.
 +
 +
The American Association of Anatomists express to Professor J. McKeen Cattell its grateful appreciation of the ability and unfailing devotion to scientific progress shown in his editorship of "Science" and other scientific journals, which, wliile serving their broader purposes, have been so often of direct benefit to anatomists.
 +
 +
The resolution was passed by the Association and the Secretary was instructed to address a copy of the same to Professor Cattell.
 +
 +
It was moved by Professor Bardeen and voted that the Association express through the Secretary its thanks and sincere appreciation of the cordial hospitality and splendid manner in which the Association has been accommodated and entertained by the Medical School of the University of Pittsburgh. In particular the thanks and appreciation of the Association are expressed to Professor Retzer and his associates in the Department of Anatomy.
 +
 +
The meeting was then adjourned.
 +
 +
Charles R. Stockard,
 +
 +
Secretary of the Thirty-Fifth Session of the American Association of Anatomists.
 +
 +
 +
 +
THE ANATOMICAL RECORD, VOL. 16, NO. 3
 +
 +
 +
 +
ABSTRACTS OF PAPERS
 +
 +
PRESENTED AT THE
 +
 +
THIRTY-FIFTH SESSION
 +
 +
OF
 +
 +
THE AMERICAN ASSOCIATION OF ANATOIVnSTS
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April 17, 18 and 19, 1919
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13G
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ABSTRACTS OF PAPERS
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1. On the -phagocytic capacity of the splenocytes of the rabbit, Willi.-ui
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H. F. Addisox, University of PennsA-lvania.
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The phagoc3i:ic capacity of the splenoc\'tes of the rabbit's spleen was studied after the following experimental procedure: Washed pigeon's blood corpuscles were injected into the chculation of the rabbit. The usual hemolysis of the pigeon's corpuscles ensued, and, as an almost inmiediate effect in a certain number of cases, was followed by the release of great numbers of mature and immature blood-cells from the bone-marrow. Both the hemolyzing blood of the pigeon and the bonemarrow cells of the rabbit, being brought by the circulating blood to the spleen, were delaj^ed within the cavernous blood channels of the pulp, and were there exposed to the phagoc}i;ic action of the splenic cells. Of the products of hemolysis of the pigeon blood, after a single injection, comparatively Uttle was retained in a visible fonii within the cells of the spleen. B}' using microchemical tests, however, an increased amount of iron-containing substances were demonstrable in the splenoC3'tes. and to a much less extent and in some cases not at all, in the endothelial and reticular cells. Towards the bone-marrow cells, however, the reaction was quite striking. By the end of six hours after injection the bone-marrow cells, notably myelocjiies and poh-morphonuclears, had been caught in large numbers within the spleen, and soon these began to be taken up by the splenoc\i:es. This process continued so that at sixteen hours the splenoc}i:es were conspicuous by their large size. Some attained lengths of 25 to 30 to 50 micra, and these larger ones contained as many as t^n to twenty ingested cells, when viewed in a 4 /x section. In this special rapidly induced, but non-infectious experimental condition, where cells and cell fragments are the stimulus to phagoc\i:osis, the splenoc>i;es are the first to act, and continue to act as the main phagoc3i;ic agents.
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S. The relation of the pituitary and thyroid glands of Bufo and Rana to
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iodine and metamorphosis. Bexxet M. Allex, University of Kansas.
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Administration of iodine mixed with flom- brings about precocious
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metamorphosis in Bufa tadpoles from which the pituitar}' gland has been
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removed. This is accompanied by a marked shrinkage of the body.
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Iodine has no effect upon the changed color produced by the removal
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of the pituitary gland. In these operated tadpoles, the absence of the
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pituitary gland normally results in scanty deposition of colloid in the
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thjToid gland. Iodine feeding does not cause anj' marked increase in
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colloid deposition in the thjToid glands of these pituitaryless tadpoles.
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Great progress toward metamorphosis was produced b}' feeding iodine
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to Bufo and Rana tadpoles from which both the pituitary- and thjToid
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glands had been removed, Therc is every e\'idence that complete
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metamorphosis would have been attained if the tadpoles had hved.
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137
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138 AMERICAN ASSOCIATION OF ANATOMISTS
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3. On the functional relations of the suprarenal gland and the retinal pigment. Leslie B. Arey, Northwestern Univereity Medical School. The influence of extremes of temperature on the position of the
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\nsual cells and retinal pigment of dark-adapted anurans differs both in degree and kind from that exhibited in other vertebrates. In the frog these temperature changes are of maximal order — such as has been associated chiefly with light-adaptation. This unusual response may conceivably depend either upon direct nervous control or on hormone activation.
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Controlled experimentation proves that adrenalin is able to induce, for example, maximal pigment expansion in the frog. Extracts of other endocrin glands fail to exert a similar influence. On the contrary, certain other observations are suggestive of nervous control.
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A method of attack has been devised which aims to test the reaUty and extent of influence of each type of activation both under noi-mal and experimentally artificial conditions.
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4. On the use of the term 'sympathetic nervous system.^ Wayxe J. AtWELL, University of Buffalo.
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The term 'sympathetic nervous system,' if it is to be retained in neurological nomenclature, should be used in the broadest possible sense, denoting that part of the peripheral nervous system which is concerned with the innervation of smooth muscle, cardiac muscle and glands. Both afferent and efferent nerves should be considered as included, and in the efferent system both preganglionic and postgangHonic neurones — those which leave in the craniosacral outflow as well as those in the thoracicolumbar. This is apparently the sense in which the tei-m is used by Professor Herrick in his Xem-ology and by Prof. Warren H. Levns in the latest edition of Gray's Anatomy. It was so employed by Professor Huber as early as 1897, although he preferred not to include the pregangKonic neurones. 'Autonomic nervous system' should be used synonjinously with 'sympathetic nervous system,' or at least should be applied to the entire efferent portion of the system. The application of 'sjrmpathetic' and of 'autonomic' to restricted parts of the efferent system, as has been done by Langley and the German school, respectively, is to be deprecated from a morphological \dewpoint.
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If 'sympathetic' is to be employed in the broad sense indicated it probably will be found desirable to adopt single words to replace the rather awkward compounds 'craniosacral component' and 'thoracicolumbar component.' The adoption of such new terms should come only after a conference of anatomist, physiologist, pharmacologist, and clinical neurologist.
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5. Pelvic fascia. Arlie Ray Barnes (introduced by B. D. ]\Iyers), Indiana University.
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One of the greatest sources of confusion in the description of the pelvic fascia has been the attempt to show that it could be traced as a
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PROCEEDINGS 139
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continuous layer over the entii^e pelvis, and, by some authors, even over the perineum.
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There are certain structural units of the peh^ic fascia, imits that can be accounted for by differences in development. The coalescence of certain contiguous layers of peritoneum and their subsequent replacement by connective tissue lamina, represents one type of fascia. The umbihcovesical and the rectovesical fascia belong to this fii'st class.
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Secondly, we have fasciae related to muscles, for example, the fascia covering the obturator internus, that covering the levator ani, and that of the perineal muscles.
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Lastly, we have that very considerable and much misunderstood mass of A-isceral mesodermal tissue smTOunding the branches of the h^-pogastric arteries on then* way to the "\dscera of the pehis.
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If we keep these three structural units in mind, ha\-ing as om* object the study of theii" arrangement, the question of continuity will become less important and will take care of itself.
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The umbilicovesical fascia. The general shape of the umbihcovesical fascia is triangular with apex at umbiHcus and lateral borders becoming continuous with the peritoneum just lateral to the obUterated umbiHcal arteries. The central portion of the umbilicovesical fascia is very closely adherent to the anterior surface of the bladder where it is verj' thin and can be demonstrated only in most favorable conditions. It ends by joining the capsule of the prostate gland. Its lateral portions join the mesodermal tissue about the vessels going to the bladder. This fascia is related to the transvei"salis fascia anteriorly; posteriorly it is separated from the peritoneum by the umbilicovesical sheath.
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The umbihcovesical sheath is the remains of mesodermal connective tissue which originally sm'rounded the allantois and umbihcal arteries. It therefore stretches from one obhterated umbihcal arterj' to the other, enclosing in its upper median portion the hgamentum unbihcale medium, and in its lower central portion, the bladder. For the bladder it foi-ms a closely adherent sheath, incorrectly called \'isceral pehnc fascia by Cunningham. The sheath has the shape and same general limits as the umbihcovesical fascia, with which it blends over the anterior part of the bladder.
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Rectovesical fascia. The rectovesical fascia, of peritoneal origin, joins the peritoneum where it leaves the bladder to be reflected onto the anterior surface of the rectum. It extends downward between the rectum posteriorly and the seminal vesicles and bladder anteriorly to be attached to the capsule of the prostate gland. Occasionally an offshoot of this fascia passes down between the seminal vesicles and bladder to be attached to the capsule of the prostate gland. Laterally, this fascia is lost as it blends with mesodermal tissue about the vessels to the bladder.
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The obturator and levator ani fasciae. The ihac fascia passes over the brim of the pelvis minor to become the pehnc fascia. It con
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140 .\iIERICAN ASSOCIATION OF ANATOMISTS
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tributes the thin fascial coat on the medial aspect of the obturator internus. This continues downward to be joined bj' the fascia lunata as mentioned above.
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The levator ani is ver}' variable in its origin and its fascial coverings vary also.
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Two terms need definition: The 'white hne' or arcus tendineus fasciae pelvis stretches from the back of the lower portion of the s}anphysis pubis to the ischial spine. It constitutes, both the lateral and anterior true hgaments of the bladder. The arcus tendineus levatoris ani has posterior attachment to the spine of the ischium, but its anterior attachment is to the superior ramus of pubis anterior to the obturator canal. When present, it helps to furnish origin for the ihococcygeal portion of the levator ani. This latter tendinous arc is not derived from a cleavage in the obturator fascia but may sometimes be adherent to the medial surface of the obturator internus fascia.
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The superior surface of the levator ani is always clothed with a division of the pehdc fascia, represented superiorl}^ in its ihococcygeal portion as the aponeurotic remains of the ihococcj^geus. Except in the case of very low origin from the 'white line,' the perimysiimi on the inferior sm-face is too thin to be dignified by the term fascia.
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Connective tissue surrounding branches of h3'pogastric arteries. The blood-vessels to the bladder are sm-rounded by mesodennal connective tissue which does not deserve the name of fascia. The rectum is surrounded by a plexus of vessels imbedded in similar tissue, constituting a covering, but again, hardly deserving to be called fascia.
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Fascia lunata. The fascia lunata is a sheath for the internal pudendal vessels and nerves. It can be demonstrated about these structures as they leave the pelvis through the greater sciatic foramen and may be traced to the urogenital diaphragm. It has a shght attachment to the sacrospinous ligament, but extensive attachments to the inferomedial border of the sacroptuberous ligament. A portion of the fascia lunata is in relation to the obturator interuus. In this connection, attention must be called to a horizontal septum, the lamina terminalis, passing from the superior border of Alcock's canal to the fascia on the lateral wall of the levator ani muscle. This limits the ischiorectal fossa superiorly. Above this lamina terminaUs, bounded laterally by the fascia covering obturator internus and medically by the levator ani, is a space, triangular in coronal section, the suprategmental space. This is usually described as a part of the ischio-rectal fossa. Anteriorly the ischiorectal fossa ends, at the level of the posterior border of the urogenital diaphragm, in several blind pockets opening posteriority and fiUed with fat.
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In the urogenital diaphragm, the sheath or fascia lunata is broken up to be prolonged about the branches of the pudendal nerve and arteiy. Thus, it is a considei-able element in the formation of the urogenital diaphragm, especially of the superior layer.
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The urogenital diaphragm. This structm'e is ordinarily considered to consist of a superior and inferior layer enclosing between them the
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PROCEEDINGS 141
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deep transverse perineal muscle, the sphincter of the membranous urethra, together with branches of the pudendal artery and nerve. The foUowine: is a more detailed statement. The inferior layer of the urogenital caaphiagm occupies the interval between the posterior border of the transveree ligament of the pehds and the posteriorsuperior border of the superficial transverse perineal muscle. The bulbocavernosus,, the ischiocavernosus, and the transverse superficial perineal muscles are sm-rounded by tubular investments derived from Colle's fascia, and on their deep surface their sheaths join the inferior laj'er.
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The superior portion of the urogenital diaphragm is composed of several imits. Anteriorly, the fii-st of these is the arcuate ligament. Xext comes the transverse Hgament of the pehds, separated from the arcuate Ugament by the dorsal vein of the perns. The third element is. a considerable septiun, 4 to 8 mm. in thickness, deep to the area covered by the inferior layer of the urogenital diaphragm and blends superiorh' with the capsule of the prostate gland. The urogenital diaphragm is attached lateralh' to the superomedial surface of the ischiopubic rami; posterioi'ly to the sphincter ani by the intervening perineal body. The bulb of the penis rests upon its inferior sm-face.
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6. The weight of the leg in living men. Robert Bexxett Beax,
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Univei-sity of ^'ii-ginia.
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"The relative weight and dimensions of the leg to the rest of the bod)^ in amputations at the thigh and above and below the knee, based on conditions obtaining in the five normal man," were secured at the request of the Red Cross Institute for Crippled and Disabled Men.
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The leg of an average-sized cadaver, not emaciated, but with almost no fat, weighed 15.56 per cent more than the water it displaced at 70° F., and the leg of another cadaver, with considerable fat although not extremely obese, weighed 10.94 per cent more than the water it displaced. The middle part of the leg about the knee was relativeh' hea\der compared with the water it displaced than either the thigh or foot.
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A tank was made into which about 500 soldiei-s legs were dipped, and the water displaced was weighed at 70° F., for the three parts of the leg: the foot, the knee, and the thigh. The water displaced by the foot is 1.6 per cent of the body weight, b}' the knee 4.7 per cent, and by the thigh 6.9 per cent. The weight of the two lower extremities is about 30 per cent of the body weight.
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The size of each part is larger in the tall than in the small, and this difference is gi-eatest ia the foot, less in the knee and least in the thigh. Those from 20 to 25 years of age have larger feet than those from 25 to 30 years, but this is because more mesophylomorphs were examined between the ages of 20 and 25 and more h3-perph3'lomorphs were examined between the ages of 25 and 30 years — a fortuitous circumstance.
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142 AMERICAN ASSOCIATION OF ANATOMISTS
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The hyperph34omorph has a long, narrow, slender foot with high arch, and the mesophylomorph has a broad, short, stocky foot with low arch. The foot of the extrcme hj'perphyloniorph displaced 873 cc. of water, the knee 2738 cc, and the thigh 3972 cc; the foot of the mesophylomorph displaced 1142 cc, the knee 3875 cc, and the thigh 5262 cc.
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7. So77ie racial characteristics of the spleen weight in man. Robert Bexxett Bean and Wilmer Baker, University of Virginia.
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The material used consists of postmortem records from the Charity Hospital and Touro Infirmary, New Orleans, La., the Johns Hopkins Hospital, Baltimore, Md., and the University of Vii-ginia Hospital, Charlottesville, Va.. and the authors wish to thank Doctor Duvall, Doctor Landfried, Doctor ^VlacCallum, and Doctor ^Marshall for the use of records from their laboratories. The spleens of 1341 white men, 1338 negro men, 441 white women and 554 negro women are utiUzed in the present study.
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The spleen of the negro is smaller than that of the white, and this difference is well marked in both normal and pathological spleens. The white male spleen weighs about 140 grams, the negro male 115 grams, the white female 130 grams and the negro female 80 grams, in the normal adult, although the number of normal spleens is too few to justify this as final.
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The racial difference is great in spite of the fact that more tall, young, well-nourished negroes and more small, old, thin whites constitute the records, and the latter difference is especially noticeable between the males. This would seem to indicate that the whites under present environment are more viable than the negroes, and the large size of the spleen in the whites may play a part in this greater viabiht}^ especially when we consider that the spleen reacts to infections, and may play a large part in the resistance of the body to disease.
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8. The weights of the human organs {preliminary report). Robert Bexnett Beax and Wilmer Baker, University of Virginia. iMaterial: Johns Hopkins Hospital Autopsy Records, twenty-two
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years up.
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Heart. Average weight: White male, 315.4 grams, white female, 265.4 grams, negro male, 325.1 grams, negro female, 262.0 grams. Most heart weights are between 200 and 425 grams in the male and between 150 and 350 grams in the; female. Racial differences are shght and sexual differences are probably due mainly to differences in body size.
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The heart weight increases with increase of stature, age, and nourishment. Of these nourishment has the most influence, age less, whereas stature has the least influence on the heart weight.
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Spleen. Average weight: ^Vhite male, 184.7 grams, white female, 165.8 grams, negro male, 144.4 grams, negro female, 117.9 grams. Racial differences are very marked, but sexual differences are no greater than should be expected.
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PROCEEDINGS 143
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Age has very little influence on spleen weight. There is a constant, though small, increase with stature, and a larger increase with nourishment.
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Liver. Average weight: ^Miite male, 1695.7 grams, white female, 1510.3 grams, negro male, 1670.5 grams, negi'o female, 1471.9 grams. Racial differences are small and sexual differences are about the same as in other organs.
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There is a steady" increase in Hver weight with statm-e, and a more marked change relative to nourishment, but the hver weight bears an inveree ratio to age.
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Kidney's. Average weight: WTiite male, 351.9 gi-ams, white female, 314.4 grams, negro male, 365.8 grams, negro female, 320.9 grams. The kidney's of the negro are sHghth' hea-vaer than those of the white, probablj' because of the better physique of the former.
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Kidney weight increases with stature and nom-ishment, especially the latter. After the age of 40 there appeai-s to be a shght decrease in kidney weight.
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9. The relative distribution of dasmatocytes in the various organs of the seven-day chick embryo. Claude S. Beck ^introduced byW. H. Lewis), Johns Hopkins Medical School.
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Small pieces of tissue from the various organs were placed in neutral red Locke's solution and then were mounted as h\Tng spreads. There are striking differences in the number of clasmatoc^'tes that are present in the different tissues of the chick. In the subcutaneous tissue clasmatoc}i;es are present in the greatest abimdance. Here they lie everywhere in the loose reticulum of the connective-tissue cells. They are absent from the epidermis. In the submucosa of the stomach, intestine, and esophagus clasmatocjiies are present in large nimibei'S, in some places they appear in swai-ms. In the subserous tissue they are numerous. In the musculature of the gut they He between the muscle bundles. They are absent in the endothehal lining of the gut. In the cornea, in striped muscle, in the pia ai-achnoid clasmatocj'tes are not so plentiful as in the preceding structm'es, but thej' are present in no small numbere. In the amnion and in the sclera there are few clasmatocj^tes. The mesonephros and the metanephros contain few clasmatocji:es, but they ai-e abundant in the walls of the Wolffian duct. In the hver clasmatocj'tes are present in verj'- small numbers. In the optic lobes of the brain and in the retina no clasmatocj'tes could be found. The method was imsatisfactoiy for the examination of the spinal cord and parts of the brain. Clasmatocji:es seem to be present in the region of the choroid plexus and in the telencephalon medium. They are absent in the choroid coat of the eye.
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10. The digestive tract of the five-day chick. (Lantern.) E. A. Boydex, Harvard ^Medical School.
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This study is based upon a new and large model of the entire digestive tube of the five-day chick. In comparison with mammahan
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144 AMERICAN ASSOCIATION OF ANATOMISTS
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embryos, scvei-al intoresting foatui-cs aro brought out, notably concerning the pancivas and its islands and accessory intestinal diverticula. But since these arc not i-eadily described in abstract, the following account is Ihnited to a discussion of retrograde changes in the epithelium of the pharj^nx. In a former paper on vestigial gill filaments in birds and rcptiles (Am. Jour. Anat., '18) the writer described tlie piT'sence of conspicuous 'degeneration vesicles,' 10 to 20 micra in diameter, in the branchial epithelium of the bird throughout the period of gill formation, that is. from the beginning of th(> fourth to the middle of the eighth day of incubation. These were described as accompanying an activity of the branchial epithelium of which the filaments seem to be the fruition. Further stud}^ has convinced me that these vesicles are distended phagocytes comparable to those found in certain pathological lesions of the human adult. Indeed, Professor Mallory, to whom they were shown, had no hesitation in describing them as endoth(4ial phagocytes. The number of these and the extent to which they are gorged with broken-down epithelial cells, one or two dozen inclusions often appearing in a single leucoc3^e, indicates a very active process of resorption which is removing the proliferating epithelium, but not fast enough to prevent the growth of filaments. Since these observations were made, a similar process, though somewhat less active, has been detected in the optic stalk and much less frequently in the outer layer of the lens and the pigmented layer of the retina. Perhaps the most striking feature is the very early period in which this resorption takes place, at a time when the primitive blood cells exhibit so little differentiation. I have been able to verify their appearance in large numbers in the branchial epithehum of chicks of 2 days and 21 hours, at which time these leucoc3i:.es contain but few ingested epithelial cells and resemble the phagocytic lymphocytes jfiguix^d by Danchakoff ('08 a). She found them within the blood-vessels of the area vasculosa of an 18-somite chick (40 houis), and in my specimens similar cells occur in small numbers in the capillaries and vessels adjacent to the branchial epitheUmn. Those of the circulating blood may well be the source of the phagoc3iies in question. It is possible, however, that they may be derived from the mesenchyiua. In that case there must be an earlier differcniation of interepithelial tissue than is described by Doctor Danchakoff ('08 b), who finds that even to the fourth or fifth day the mesench3'mal cells aix> wholly undifferentiated, quite alike and equipotential. This accords Avith an origin by migration from the vessels, but the evidence is not conclusive.
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11. On the interaction of primary femoral ossification, thigh muscular differentiation, knee and hip-joint formation, during the period of rotation of the hind limb of the pig (Sus scrofa). Eben J. Carey, CJreighton Medical College.
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It has been shown previous^ (Anat. Rec, vol. 11, no. 6, 1917, and vol. 14, no. 1, 1918) that th(^ earliest bon(! formation in the femur coincides in time with the manifestation of contractility, of the thigh mus
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PROCEEDINGS 145
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culature and in site with the region of greatest mechanical tensile stress incidental to the rotation of the limb and bending of the femur. From du-ect observation, it seems probable that there is a definite action of the developing parts of the thigh upon one another resulting in dependent differentiation. This incipient differentiation, however, is not wholly dependent, since the structure of the reacting, as well as that of the stimulating part is contributory to the quality of the effect.
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The most rapidly growing part of the thigh is the skeletal core. This blastemal skeletal zone of growth appears to exert a traction force upon the contiguous sjnic^-tial mesenchjTne. This mesench>Tiie is first condensed as premuscular tissue with its nuclear long axis in the du-ection of skeletal growth. The c3d;oplasm of the premuscular mass becomes drawn out and subsequently the myofibrils appear as elongated strands, also, dhected along the lines of skeletal growth. As the myofibrils differentiate and functionate in embryos of 15 to 20 mm. in length, rotation of the hind limb is begun. There is also a tendency on the part of the myofibrils to restrict the longitudinal growth of the cartilaginous skeletal core. The femoral rod, which is outlined by a condensation at the future knee and hip joints, by this time, is consequenth' bent. The weakest part of the rod is at the middle on its convex aspect. It is here that eventually the first steps in fibrogenesis of the periosteum, degeneration of the cartilage cells and genesis of primary bone appears in embrj^os 25 to 32 mm. in length.
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The hip-joint cavity appears in embryos 19 to 24 mm. in length. This ca\'ity formation coincides with the first adducting action in the rotation of the hind limb. Likewise, the formation of the retropatellar cavitA' at the knee, which appears in embryos 25 to 30 mm. in length, coincides in time or shorth^ follows flexion of the knee joint.
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From the order of appearance of the differentiatmg blastemal skeletal core, mj^ofibrils, cavity formation of the knee and hip joints, and primary femoral ossification there appears to be a definite interaction of the developing parts qn one another, during the rotation of the hind limb which points to dependent differentiation and not purely self -differentiation.
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12. On the development of the lymphatics in the stomach of the embryo pig.
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James R. Cash, Johns Hopkins University.
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In this study the hanphatics of the stomach were followed by the method of injection. In Hving embryos measuring from 30 to 60 mm. the injection was made through the retroperitoneal sac. In embryos measuring from 80 to 150 mm. injection was made directh' into the sto.mach wall at the lesser curvature. In the embryo pig the retroperitoneal sac is large and its anterior end lies opposite the coeliac axis.
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The hmphatics of the stomach arise from the anterior end of the retroperitoneal sac by two main trunks. Thus, in their oiigin the gastric lymphatics are analogous to those of the intestine which arise by two forks, right and left, and form an arch around the wall.
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146 AMERICAN ASSOCIATION OF ANATOMISTS
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The right gastric vessels pass up behind the stomach and invade it at three points: 1) at the esophagus by nmnerous vessels which form a xery dense periesophageal ring; 2) at the lesser curvature by a great mass of vessels which pass directly to the stomach wall; 3) at the pylorus by one or two \essels.
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The left gastric trunk (splenic trunk) di\ades into two branches, One passes anteriorly directly to the cardiac pouch. The other passes through the splenic ligament, to the hilum of the spleen, then traverses the gastrosplenic hgament to the center of the greater curvature of the stomach, along which it ramifies to right and left. These h-mphatics then anastomose, both over the anterior and posterior walls, with those from the lesser curvature where connections are formed with the lymphatics of the esophagus and duodenum.
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13. Reaction of cells in tissue culture to ether. James R. Cash, Johns Hopkins Medical School.
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Connective-tissue cells, muscle buds, and nerve fibers from explants of embryonic chick tissue of former Lewis solution were studied under influence of ether vapor. Within one to three minutes numerous definite, clear, homogeneous vesicles bulge out at points on surface of cell. Many of these rapidly change shape, assuming protean forms.
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Following sublethal amounts of ether vapor, the vesicles flow back and the cell assumes norrpal appearance. After slow ether death the vesicles remain active; but when rapid death ensues, the entire cell assumes a rounded form, and few, if any, vesicles appear.
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There are concomitant changes in the nucleus, nucleolus, mitochondria, and other cell granules.
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Similar changes are readily produced bj^ subjecting old cultures (three days) to markedly hypotonic salt solution. Immediately (within 30 seconds) nimierous vesicles appear, change shape characteristically for a short time, and flow back into the cell. Such changes are less readilj^ produced in young, healthy cells. Similar vesicles have occasionally been noted in degenerating cultures (four to five days).
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From such observations it would seem that these vesicles are evidence of degeneration by which changes at points in the cell membrane occur, allowing rapid inhibition of water. In the functionally active cell this change is probably overcome by the internal metabohsm of the cell.
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These vesicles are difi"erent fr.om the pseudopodia described in either the resting or the dividing cells.
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14. Mesenchyme and its biological properties. V. Daxchakoff, Columbia Univei-sity.
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It has been shown lately that only under typical conditions does the greatest part of the embryonic mesenchjane become the anlage for the interstitial tissue of various organs. It may, however, under other conditions differentiate into products which though encountered in a normal organism do not enter normally into the constitution of a definite
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PROCEEDINGS 147
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organ. As seen from the lantern slides and microscopical preparations, the embryonic mesench\Tne of various organs may greatly proliferate under definite experimental conditions and develop into large accumulations of granuloblastic tissue.
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In the normal development the embryonic mesenchyme transforms in most of the organs into 'interstitial connective tissue.' Xo special function has been ascribed to this tissue besides the holding together of the specific elements characteristic of various organs. It is true that a phagoc^iiic acti\'ity has been often described as belonging to the cells of the interstitial tissue.
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Xew data concerning the remarkable relationship developing in a culture on the chick aUantois between adult splenic mesench^Tne and proliferating cells of the EhrHch sarcoma seem to point out the fact that the phagocj'tic and digestive power of the adult mesenchj-me maj' be an important factor in the phenomenon of the immunity observed through the animal kingdom.
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As seen from the lantern slides, tumor cells either in the resting period or in mitosis are surrounded by mobihzed cells of the splenic mesr-nchMne and submitted to a gradual complete digestion. This phenomenon is not altogether different from the ingestion of er^'throc^'tes of. blocks of disintegrating tissue by a mobihzed mesench\Tiial cell, frequently observed in the organism. Only in this case the ingestion is effected by a group of mesenchjTnal cells.
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The fate of the ingested cells in both cases is identical; they are digested in the first case intracellularly; in the latter, intraplasmodically. If I may say so, th^ phagocAlic and digestive acti\'ity of a mesench}Tiial cell is usually directed against dead particles and possibly weakened cells of its own kind. In the case of heteroplastic tissue, however, mesench^Tual cells may ingest a h\'ing cell and submit it to a complete digestion. The biological properties of the mesenchjTiie, i.e., its digestive power, must certainly be taken into consideration in our attempt at sohiLng the problem of the resistance of the organism against heteroplastic grafting.
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15. An experimental test of the possibility of differential selection of germ cells (in the fowl). C. H. Daxforth, Washixgtox Uxiversity School of Medicine.
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It is commonly assumed that heritable differences in adult structiu^s are due to more or less specific detemiiners thought to be present in the genu cells. If this seemingly well-founded assumption is vahd, it follows that the geim cells produced by a heterozygous animal must fall into several classes, and the question natm-ally arises a.s to whether such germ cells may not react differently to chemically or physically changed surroimdings, or at least show somewhat differe*nt potentialities in their competition with each other. In order to test this question, cocks heterozygous in regard to brachydactyly, polydactylj'. color, and shape of comb were mated to hens homozygous for these traits in their recessive fomis and a record made of the numbei'S in each
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148 AMERICAN ASSOCIATION OF ANATOMISTS
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class of young produced before and after treating the males with alcohol. The data thus obtained indicate that the administration of alcohol b}' Stockard's inhalation method altei-s the proportion of certain classes of chicks produced. This is interpreted to mean that (contrary' to Pearl's opinion) a mildly toxic agent may select between gemi cells on the basis of the IMendehan determiners which they carry. Incidentalh', it may be observed that a recognition of the fact that the probability that a germ cell will function is in some degi'ee dependent upon the determiners which it carries, may lead to a satisfactory explanation for orthogenesis.
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16. A study of coagulation in embryonic blood. V. E. Emmel, University of Ilhnois, College of Medicine.
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In the coui-se of an experimental study of the origin of the non-nucleated er3i;hrocj'tes or erythroplastids (Emmel, '14) certain striking differences were observed in the coagulation of embryonic blood. In the present investigation, undertaken in cooperation with two of my students, Doctors Fish and Levinson, a more extended stud\^ has been made of the subject. It is the purpose of the present report to present certain results attained in experiments made on the blood of pig embryos at various stages of development.
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17. On the segregation of macrophage and fibroblast cells by means of vital acid dyes and on the cause of the differential effect of these substances. Herbert McLean Evans and Katharine J. Scott, University of CaUfornia.
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The two great cell strains of the connective tissue of mammals — the fibroblast and the macrophage cells — exhibit a pronounced and characteristic difference in their reaction to intra vitam acid dyes. This difference shows itself in the appearance of two sharply separated types of response to the dye — in the size, form, and number of the vital dye 'granules' — and the fact that these types of vital dye response are associated with those other characteristics which permit us to designate fibroblast and macrophage cells. The mitochondrial apparatus of the connective-tissue cells cannot be said to be electively stained by means of th(; vital acid dyes. The vital dye 'granules' in the case of both fibroblast and macro'phage cells are neither chemical combinations of the dj^e with the protoplasm nor phj^sical tinging of preexisting cell oi-gans, but are actual accumulations within the cell of the vital dyestuff employed in fluid, high colloidal, flocculated, or crystalUne form. The number and size of the dye 'granules' within the cell in the case of any one dye are dependent on the concentration and time of dye dosage, and in the case of various dj^es, follow a similar law except that there occur characteristic differences in the structures created by various dyes when a standard dosage is employed. In the case of several dyes, among several hundred which were tested, there occur color changes in the dye substance in accordance with whether it is in solution or in solid or semisolid form. This
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PROCEEDINGS 149
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metachromasia has been carefully investigated by Werner Schulemann and one of us. It would appear to prove conclusively that the dye is at first in soluble state in its place of deposit within the cell, but that it undergoes concentration so as to be thrown out of solution, the solid form, whether amorphous or crystalline, showing a different color from the fluid. By certain dosages with some of the numerous dyes of this series, a true crj^stallization of the vital dye can be made to occur within the living cell. The employment of acid dye of marked color difference, but of similar physical state, produces vital dye 'granules' of mixed color; the employment of differently colored dyes of markedly different physical state, produces vital dye structm-es in which only a partial color contamination occurs. All of these phenomena ai"e exhibited by the dye deposits of both macrophage and fibroblast cells. The ingestion of these dyestuffs is usually associated with their separation from the hving protoplasm by virtue of a segregating power of the cell; for such segregation, granules, minute vesicles and vacuoles of many sizes may be created in addition to those already present in the cell. We have called the ensemble of these structures the Vacuolar apparatus' of the cell. The vacuolar apparatus is electively stained bj^ neutral red and by certain other basic dyestuffs when these are applied supra vitally. In the case of the fibroblast cells, but never in the macrophages, the vacuolar apparatus shows an interesting tendency to exhibit pecuhar filar modifications so that elaborate thread structm'es may result in areas where the dye application has been particularly intense. With the exception of this peculiar or qualitative difference, the usual difference in the vital staining reaction of macrophage and fibroblast cells is to be interpreted as a quantitative one only, and the nature of the dye 'granules' in both cells is identical. The quantitative difference in reaction to the vital dyes is, however, a remarkably sharp histophj^siological test. The difference in the behavior of the two cell strains is shown both by theu* unequal power to store and to liberate their protoplasmic deposits of these substances. The power to store these vital dyestuffs is on the part of the macrophage greatly in excess of a similar capacity shown by the fibroblast cell. The macrophage vital dye deposits are, conversely, more susceptible of decolorization and less permanent than are the more minute deposits in the fibroblast cell.
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The detailed cytological evidence here summarized will be found in a contribution to the Carnegie Memorial Volume in honor of Prof. Franklin P. Mall and the correlative data on vital dyestuffs of the acid azo series, in a monographic summary by one of us in conjunction with Schulemann and Wilborn which has lain ready for publication for some time.
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18. Studies on sex in the hermaphrodite mollusc Crepidula plana. III.
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Transference of the male-producing stimulus through sea-water. Har LEY N. Gould, Universit}^ of Pittsburgh.
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The gastropod mollusc Crepidula plana passes through a male phase^ a transitional phase, and a female phase during its life. The male phase
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150 AMERICAN ASSOCIATION OF ANATOMISTS
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is unstable and occurs only as the result of a stimulus furnished by an individual of the same species larger than the one stimulated.
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Complete isolation of small sexuallj' undeveloped specimens over long periods shows that no development of male characters takes place under such conditions further than the formation of a few spermatogonia. In time female charactei-s appear. Small sexually undeveloped individuals confined at fixed distances of from 4 to 7 mm. from large females, where contact is prevented, will in a majority of cases develop male characters to various degi'ees of maturit3^ Fewer and less well-developed males are produced under such conditions than when the small animals are nearer the source of stimulus.
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Large individuals of Crepidula fornicata, a species related to C. plana, have not been found to induce male development in small Crepidula plana except in a few doubtful cases.
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The stunulus to male development acts in such a manner as to indicate that it is a substance given off from the bodies of the large Crepidula plana, diffusible through sea-water, but very unstable.
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19. War deafness and its prevention: cochlear observations. Stacy R. Guild, University of Michigan.
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At ^Minneapolis were reported new methods of testing ear protectors. Of the results of the animal tests the conditions of the middle ears only could be reported then. The present report is of the conditions in 92 cochleae, these being from control and 'protected' ears. Technique: injection fixation with Zenker-f ormalin ; celloidin embedding; decalcification; 'double' embedding in paraffin; 7m sections; Heidenhain's hematoxylin and benzopurpurin. Definite lesions to the organ of Corti range from the loss of occasional outer hair cells to almost complete disintegration of the epithelial parts. For purposes of tabulation, the lesions have been designated first-, second-, third-, and fourth-degree injuries; their distribution is shown by charts. The division into more and less efficient groups of protectors is not as sharply marked by the cochlear conditions as by the middle-ear conditions and by the tambour tests; each of the protective measures failed to prevent definite cochlear lesions in one or more of the ears with which it was used. Even here, however, a ranking of the devices is evident. Both from the standpoint of the tests and of special miUtary requirements for field use by troops, the 'Tommy' appears to be definitely the best of those tested. The distribution of the cochlear lesions is also of intere'st in connection with the physiology-- of hearing. Four reports of this work, submitted to the National Research Council, have been published in the Journal of Laboratory and Clinical Medicine, September, 1917; Januaiy, 1918; March, 1918, and January, 1919. (Lantern.)
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20. The anatomy of the 7-mm. opossum embryo. Chester H. Heuser . The Wistar Institute of Anatomy.
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As a part of the plan to work out the development of the systems of organs in the opossum, the anatomy of a stage similar to the 12-mm.
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PROCEEDINGS 151
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pig is being especially studied. The illustrations are based largely on a series of dissections from three embryos. In one the cerebral and spinal nerves were uncovered and the trunks traced to include the fine terminal branches. Wax reconstructions were made of the phar>Tix, digestive and respirator}' systems, heart, and the left jugular honph sac. I have also made vascular injections in the hving embiyos. Fifth aortic arches are present.
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The third pharjTigeal pouch derivatives have become separated from the pharjTix. The ganghon nodosum is fused with the cer^dc^l sinus, and there arises from the ganglion a cord of cells which, with a strand from the thj-mus, makes another connection with the smus. The hypoglossus is embedded in the nodosmn, but does not touch the thymus. The superior lar^mgeal nerve is distinct: it extends from the mesial border, of the cord above referred to and runs between the thymus and the parathja-eoid.
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The jugular h-mph sac has become transformed into a much-divided structure with smaller and larger spaces. In an injected embryo of the same htter the hTiiph sac received no ink, although the injection of the blood vessels is complete.
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21. Experiments with the thyroid, hypophysis and pineal glands of Rana sylvatica. E. R. Hoskixs and M. M. Hoskixs, University of Pittsburgh.
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A. ThjToid. In 105 young larvae the thjToid anlage was cut to pieces, but left in situ, and an additional thyroid anlage transplanted into the animal. Some of the larvae developed accessory th\Toids, but this had no effect except perhaps in a few larvae that metamorphosed while small. The time of metamorphosis was not hastened.
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B. Hypophj'sis. The hypophyseal anlage was removed from 116 young larvae after the method of Smith and of Allen, with the usual results in most cases. A few larvae became black. Some of these black larvae metamorphosed, but one did not, although it grew much larger than normal.
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Transplantation experiments of the hj-pophyseal anlage into 62 young larvae gave negative i-esults, although some of the transplants gr-ew.
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G. Pineal. The pineal was r-emoved from 70 young larvae, but regenerated either partially or completely and the larvae grew normally. The anlage of the pineal was transplanted into 19 young larvae. It failed to gr-ow.
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D. Some of the larvae of the thjToid and hypophysis operations developed small accessory mouth-parts. These were mostly ectodermal outpoiichings, but in some of them muscle fiber's developed. One of these opened into the oral cavity.
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THE AXATOMICAL RECORD, VOL. 16, NO. 3
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152 AMERICAN ASSOCIATION OF ANATOMISTS
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22. Observations on thyroidless Rana sylvatica larvae kept through the
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second scasori of normal metamorphosis. E. R. Hoskins and M. ]\I.
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HosKixs, Univei-sity of Pittsbm-gh,
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The larvae nearly reached their maximum size the first summer (66 mm.), but gix'W again sUghtly during the winter and more during the second spring and summer (72 mm.). They became relatively longtailed, the legs grew ^ mm., the head and back flattened, and the eyes became relatively far apart.
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The brain acquired a shape practically mature, but at a size much larger than normal, and the liver became nearly mature in shape. The hypophj'sis became relatively very large, especially the inferior lobe, and this lobe showed an increase in the relative number of eosinophiHc cells. The anterior and superior lobes showed Uttle structural differentiation. The thjTnus glands persisted and became relatively and actually large. They retaint'd the larval shape and structure. The epitheloid bodies (parathyi'oids) became relatively large. The spleen became large, but was roughly proportional to the size of the larva. The kidne3^s enlarged both actualty and relatively. The internal gills persisted and the lungs became large and functional. The intestines grew long and remained larval in type, as noted by Allen. The ovaries became large and large oocytes developed. Maturation was not seen and oviducts did not develop, so the animals were not sexually mature. The testes became mature and formed spermatozoa which escaped into the kidneys.
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By successive extirpations of the end of its tail, a larva was made to regenerate 38.5 mm. of tail. It regenerated one small hind leg once, but not a second time after the regenerated leg was removed. The amount of tune required for regeneration of the tail gradually" increased.
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A larva placed in a moist chamber lived two days, its volume decreased 18 per cent, its tail shrank 24 per cent, and its intestine became strongly contracted to about half the nomial size, but did not shorten perceptibly.
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2S. An analysis of the theories -of pulmonary evolution in the Mammalia.
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Geo. S. Huntington, Columbia" University.
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The phylogeny of the mammalian lung is considered with especial reference to the development of the extant bi'onchial architectonic types and their evolutionary significance. The conclusions lead to a re"\dsion of the prevalent views of intrapulmonary organization. The paper discusses:
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1. The reduction theory of Aeby ('80) and D'Hardiviller ('97) in which the modern problem of bronchial interpre^tation found its beginning.
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2. The theory of the migration of bronchial components, propounded by Willach ('88) and Narath*('92, '96, 01).
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3. The summary of the results reached by the writer constituting what can briefly be defined as the selective theory of mammalian pulmonary specialization.
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PROCEEDINGS 153
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24. The effects of inanition in the young upon the ultimate size of the body and of the various organs in the albino rat. C. ]M. Jacksox and C. A. Stewart, University of ^Minnesota.
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Thirt3'-eight litters were used; 113 rats survived, 35 male and 35 female test rats, 27 male and 16 female controls. Groups were underfed from birth to three, six, and ten weeks of age, and from three weeks to twenty weeks or to nearly one year. There upon the test rats were full}' refed. They grew variably, but remained permanently stunted, failing to reach the adult size of the controls. Stewart ('16) found perfect recovery after underfeeding from three to ten weeks of age. The ultimate effect, therefore, varies according to the age of the animal and the extent of the underfeeding period. This is in agreement x^ith , the results of Aron and Brtining, but disagi*ees with Osborne and ]Mendel.
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Forty-five of our rats (28 test and 17 controls) were autopsied. The organs in the test animals were compared ^\'ith the nomial at corresponding body weight. Body length and tail length appear shghtly subnormal; head, limbs, and tiunk nearl}' nomial in weight; skeleton, integument, and musculature usuallj^ sUghth' subnormal, \'isceral group shghtly above normal, and 'remainder' variable.
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Of the indi^-idual organs, the brain, spinal cord, hj-pophysis, and lungs average shghtly subnormal; the ovaries distinctly so. The heart and alimentarj^ tract are shghtly, and the testes and epididymides definitely, above normal weight.
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"VMiile some abnoi-mahties thus appear, they are usuaU}' shght, and in general the organs and parts are nearly normaUj^ proportioned in the permanently stunted rats. Thus earh'- starvation apparently retards the later gi'o-n-th process of the body as a whole.
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25. Reversal of striation in contracting muscle. H. E, Jordax, University of Virginia.
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Merkel fii*st ('72) recorded the phenomenon of stripe reversal in contracting muscle. The investigations of RoUet ('85) and Tourneux ('92) support Merkel's interpretation, and add the concept of a 'contraction band.' The dark band (Q) of uncontracted fibers is bisected by the mesophragma; the dark (contraction) band of contracted fibers is bisected by the telophragma. ^lerkel and Rollet beheve that the anisotropic substance of uncontracted fibers divides along the mesophragma and moves in opposite directions against the telophragmata to form the dark stripes of contracted fibers. Englemann ('73), Van Gehuchten ('86) and Schaefer ('91) dispute the accuracj^ of such interpretation. Schaefer explains the apparent revei-sal of striations as an optical effect consequent to the condensation of the J-substance about Z and a relative rarefaction of the Q-substance about M, due to an absorption of the isotropous by the anisotropous constituent. Englemann and Van Gehuchten have apparently proved by means of micropolariscopic studies that the anisotropic substance does not alter its position dm-ing contraction, Schaefer, by means of Rollet 's gold
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154 AMERICAN ASSOCIATION OF ANATOMISTS
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chlorid tochnic. claims to have established the same fact. A reinvestigation of the phenomenon of stripe inversion in the wing muscle of wasp, by various combinations of fixatives and stains, and studies in hypo-, iso-, and hypertonic solutions, confirms my former conclusion that during contraction there is a true i*evei"sal of striations as regards a deeply staining constituent of the Q-disc and the contraction band, and gives the key for the reintei-pretation of Schaefer's results in terms of the action of a hypotonic solution.
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26. The sympathetic innervation of the testis in the dog. Albert Kuntz, St. Louis Universitj^ School of Medicine.
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The sjinpathctic nerve supply' to the testis is derived fi-om the third,
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fourth fifth, and sixth lumbar segments of the sjTnpathetic trunk. These fibers descend along the course of the spermatic artery and vein. The hj'pogastric nerve supplies some fibers to the pelvic end of the vas deferens; however, these fibers probably do not reach the testis.
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Sjanpathetic fibers are supplied to all structures in the spermatic cord and testis which contain smooth muscle. There is no evidence that sympathetic fibers terminate in relation either to interstitial cells or spermatogenic elements.
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Section of the sympathetic nerves to the testis results in degeneration of the seminiferous tubules.
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27. The development of the cross-striated myofibril in the heart muscle of the chick embryo. Margaret Reed Lewis, Carnegie Institution, Johns Hopkins Medical School.
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'Ry fixing the total chick embryo so that the heart is slightly extended, cross-striated myofibrils, of the same pattern as those found in embryos of two to four days, can be demonstrated to be present in the heart muscle of embryos of ten myotomes. This pattern is composed of two light bands and one dark band, all about the same width, and a wid(>r gi-ay band, arranged as follows: Light (J-band), dark (Z-band), light (J-band), and gray (Q-band). These bands are usually arranged in fibrils whose width, thickness,^ and length vary. Only a few fibrils are found at the stage of ten myotomes, but in embryos of fifteen or more myotomes the fibrils are numerous. A fibril extends in the same focus past several nuckd. The number, length and character of the fibrils formed depend upon the solution used in fixation.
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Living chick embryos mounted in Locke's solution contain no fibrils in the heart muscle.- The cross striations can occasionally be found spread out in an extremely thin laj^er on the surface of the cell. They have little d'-pth when focused; they can be observed only in that region of the cell surface which is in focus, and never extend past several nuclei. The mitochondria can be ck^arly observed especially in preparations stained with Janus green. They are not elongated nor are they arranged in a dcifinite row. In no case did a mitochondrium extend beyond the limit of a cell.
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PROCEEDINGS 155
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28. The centriole and centrosphere in degenerating fibroblasts of tissue cultures. Warren H. Lewis, Johns Hopkins Medical School.
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In fibroblasts of tissue cultures undergoing vacuolar degeneration a centrosphere develops around the centriole. The centriole in the normal fibroblast lies close to the nucleus, the mitochondria do not appear to have any definite relation to it. As degeneration progresses, vacuoles increase in number and surround the enlarging centrosphere, and the mitochondria become radially arranged about it. The centrosphere may attain a size greater than the nucleus. There is much variation in the structure of the centrosphere in fixed specimens. The centriole may be smi'ounded by a finely granular zone varying in thickness in different cells. A homogeneous clear zone may intervene between centriole and granular zone or a homogeneous medullary and a homogeneous cortical zone may intervene. The finely granular zone may not be present. There are various other types of centvospheres and various gradations between them even in the same culture among cells side by side. Such differences indicate perhaps that the cells when fixed are often in different phases of metabolic activity. The coagulated c3i:oplasm is more dense about the centrosphere than about the nucleus, and the framework between the vacuoles radiates from it, not from the nucleus. This orientation of the various structures in the degenerating fibroblasts about the centriole and centrosphere, and their central location suggest that the centriole and not the nucleus is the center of metabolic activity or that there is an increase of the activity of the centriole in degeneration.
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29. Studies on the longitudinal muscle of the human colon, with special reference to the taeniae. P. E. Lineback, Emory University.
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This investigation covered a series of embryos ranging from 26 mm. to the new-born, in all, thirty-five different sizes were used. It also included experiments on the guinea-pig's caecum, and a few observations were made on the human colon in life.
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The longitudinal muscle originated in the caudal end of the colon at about the 40-mm. stage and rapidlj extends to the caecal end, first along the mesenteric line. This growth is closely followed by a complete layer which encases the tube, the whole being finished before definite taeniae appear. The mesenteric portion becomes thickened and develops into the first taenia, the other two subsequently appear as thickenings in the muscle wall and by the 105 mm, stage the three are definitely formed.
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The production of taeniae of the adult state is based upon two factors and stages — a growth factor in an earl}^ stage and a functional factor in a later stage. The functional phase involved the combined action of the longitudinal and circular muscles and results in the production of sacculations as well as accentuating the taeniae. Further work is being done along this line.
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156 AMERICAN ASSOCIATION OF ANATOMISTS
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50. Brain repair in the rat vitally stained with trypan-blue. Charles Clifford ]\Iacklix and oMadge Thurlow AIacklin, University of Pittsburgh and Johns Hopkins Medical School.
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Healing aseptic wounds in the brains of rats, made by stabbing with a i*ed-hot needle under ether anesthesia, were studied in a series of animals, covering the first seventy-four days of repair. Trypan-blue, in 1 per cent aqueous solution, was administered intraperitoneally two days before death.
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^Mononuclear phagocytes soon appear. They are quite numerous and contain much fat, blood pigment, etc., but very little dyestuff in comparison with the macrophages of injured muscle and connective tissue, such as appear in the vicinity of a fractured bone (^Macklin, Anat. Rec, Jan., 1918). Dj^e was found in them only during the fii-st fomdays, and in this respect also they differ from the macrophages of inflammation of other tissues. Often the small vessels are outlined by rows of dye-containing cells and the use of the proper stains, and examination of fresh material shows that these cells are filled with fat. So close is the association between the amoeboid fat-containing phagoC5i;es and the blood-vessels (the walls of which contain fat droplets) that the inference is strong that fat is thus gathered up and passed into the blood-vessels, its absoiption being so accomplished. The tr\T3anophi]ic cells are apparently developed largely from local neuroglia cells. Mitoses are abundant at the second and third days.
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Other interesting features are the staining of the arachnoid cells of the lesion area, the homogeneous blue staining of the neighboring blood-vessels, and the pale difi'use staining of the area of inflammatory oedema during the early stages.
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51. The value of study of the gill-arch system in topographical anatomy. Matthew Marshall (introduced by Robert Retzer), University of Pittsburgh.
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A study of the gill-arch derivatives simplifies the understanding of the relationships which obtain in the adult derivatives of these structures. A general statement of these simple relationships follows:
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1. Interrelationships of derivatives of the same gill arch: A. The nerves are external to the artery and bar derivatives. B. The arteries are external to the bar derivatives. C. The muscle derivatives have inconstant relationships with the bar, artery, and nerve derivatives.
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2. Interrelationships of derivatives of one gill arch with those of another gill arch: A. Derivatives of one gill arch when related to those of a higher gill arch are internal to them.
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 +
3. Relationships of the longitudinal aortic derivatives: A. Dorsal aortic derivative — internal to other gill arch derivatives. B. Ventral aortic derivative — external to other gill arch derivatives.
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4. Exceptions can be accounted for on the basis of mechanics which comparative morphology indicates have been active.
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PROCEEDINGS 157
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52. Xote on the lun^ of the rabbit and of the guinea-pig. William Sxow Miller, University of Wisconsin.
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In a paper on the vascular supply of the pleui-a puhnonalis, published in 1907, I made the following statement: "the histological structure of a given organ may differ in animals of different species. . . . Because a given structure, or relation of structm'es, is found in, for example, rabbits, it is no criterion that the same structure, or relation of structm-es, will be found in rats, and the inverse is true." Recent studies have shown that, while in some animals the masses of hmiphoid tissue present in the limg receive theii' blood suppty from the bronchial artery, in the rabbit branches from the pulmonaiy arteiy are distributed to these masses, especially to those situated at the point where bronchi di\ade. This has an important bearing on any experimental work which concerns the vascular supply of these masses of l^Tiiphoid tissue.
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Klein, manj^ years ago, called attention to the presence of smooth muscle in the pleura of the guinea-pig. I have found that in the walls of the bronchial tree and in the walls of the blood-vessels there is, in this animal, proportionately a greater amount of smooth muscle than in the same structures in the animals ordinarily used in the laboratory.
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53. On the antiquity of certain histological elements of bone. Rot L, !MooDiE, College of Medicine, University of Illinois.
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The first bone to develop on the bodies of vertebrates arose in the ectodermal tissues suiTOunding and capping the dorsal-fin spines of the Ordo\4cian and Silurian vertebrates, the primitive sharks of the Paleozoic. Histological study of this ancient tissue reveals no evidence of Haversian systems or lamellae, but the lacunae with short, irregular canalicuh are to be found aiTanged m an indefinite way in the trabeculae surrounding the large vascular spaces.
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The oldest known Haversian system occurs in a Devonian limg fish. Here the Haversian canal is large, the lameUae are definitely concentric, and the lacunae, ^ith short canahcuh, surround the canal. There is no apparent communication between the canaliculi of the lacunae and the system has a primitive appearance.
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The perforating fibers of Sharpey are seen for the first time in the history of the vertebrates in the mosasaurs of the Cretaceous, where they are arranged in large bundles and have considerable length. So far as ascertained they do not perforate the lameUae, and are apparently more numerous near the sm-face of the diaphysis. They are especially abundant in a sm-face lesion of osteoperisotitis and have not been seen in normal bone.
 +
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Osteoid tissue is seen in the same lesions, similar in all respects to the osteoid tissue of modem times. Osteosclerosis and osteohypertrophy occur sharply marked in the oldest known fractured bone from the Peimian of Texas.
 +
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The indications so far observed in the material examined, covering nearly the whole range of the evolution of the vertebrates seen in geological history, show that the degree of development has been smaU
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158 AMERICAN ASSOCIATION OF ANATOMISTS .
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since the middle of the Paleozoic, the modern plan of l^ony tissues having been laid down very early in the history of the vertebrates.
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84- Amitotic kanjokinesis and generel histogenesis. I. P. Munson,
 +
 +
Ellensburg. Washington.
 +
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Mesodermal tissues are structurally related. Their obvious differences are due to the nature of the intercellular substances and the intracellular matrix. The cells of these tissues are distinct physiological centers, but they arc not morphologically separated. Although, as aggregates, they seem to fonn solid masses, as in muscle, cartilage, and bone, they are made up of net-like membranes, either living cavities or superun posed. The anisotropic, structural elements of these membianes, consist of nucleus, centrosome, and sphere, with astral rays. These rays are continuous with the cji^oreticulum which may be embedded in a solid, hyaline, or liquid matrix. The rays of one cell area are continuous with the lays of the neighboring cell areas. All the cells are connected by intercellular bridges of astral rays. Cell membranes do not exist. The boundaries are sometimes perceptible as enlargements of peripheral fibrils, or as granules deposited between the filx^rs at the original cell iDoundary. It might be designated as a sjTicytium, if the connotation of that term be modified accordingly. . Endothelium, connective tissue, cartilage, bone, and muscle are organically connected with each other, as are the cells of these tissues.
 +
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Although kaiyokinesis as well as amitosis are rarely seen in these tissues when fully differentiated, cell multipHcation is not as unusual as is generally supposed. By slow growth, the cells of these tissues divide in a manner that is neither karyokinesis nor amitosis, but rather a combination of those modes of cell division. A permanent and constant centrosome, which is a secreting organ as well as the center of cytoplasmic growth and the morphological center of the astral system, is found eith(?r at one pole of the nucleus, in the notch of the nucleus, or wholly within it. The nucleus divides by a process of cleavage, without fonning a spindle. The centrosome may or may not divide at the same time. Aitv.r the division of the nucleus, the; centrosome usually moves in between the two halves of the nucleus and may then gradually divide. The two centrosomcs gradually grow apart, but their astral rays continue to unite them after an equatorial plate of granules have been deposited between the two halves of the cell. In this way cell multiplication can go on without severing the connection between the cells. To avoid a new term, I have called this mode of cell division amitotic kaiyokinesis. In striated muscle the main facts are similar, though the details varj'. A sacromere bounded b}^ the membranes of Krause is originally a cell with nucleus and centrosome.
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Permanent and constant ccnti'osomes also exist in some nerve cells. The neurofibrillae are extended astral rays. There is probably a similar continuity between neurons at the synapse, which marks the original boundary between the neurons. . The tentative hypothesis is suggested that the neuraxon is a bundle of astral rays connecting nerve
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PROCEEDINGS 159
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cells, as similar fibers connect bone cells, and are responsible for the canaliculi of bone.
 +
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One conclusion to be drawn is that cells are organized, and that the cell theory is at fault when it fails to recognize the morphological contmuity of protoplasm in many celled organisms. A mechanistic explanation of this cell organization is a problem suggested by the studies here announced.
 +
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So. Studies on the mammary gland. V. The effects of inanition on the
 +
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developing mammary glands in male and female albino rats from birth
 +
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to ten weeks of age. J. A. Myers, University of Minnesota.
 +
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Severe inanition retards the growth of the milk-ducts of the female
 +
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rat dm-ing the first week, but apparently does not completely stop their
 +
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growth. In animals held at bhth weight for a longer time the ducts
 +
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cease to grow and remain in a condition shghtly more developed than
 +
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at the time of birth. If after the first week the gross body weight of
 +
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the animal is allowed to increase so as to correspond with that of a
 +
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normal animal of one week the milk-ducts fail to develop to the same
 +
 +
extent as those of a normal annual of corresponding body weight. This
 +
 +
also holds true if the body weight of the underfed rat is allowed to equal
 +
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that of a normal animal of two weeks.
 +
 +
The growth of the milk-ducts of male rats is retarded by inanition in a manner similar to that of the female.
 +
 +
The nipple grows very little during inanition, being elevated above the surface only slightly in young rats starved severely for eight to ten weeks.
 +
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Severe inanition for a short time at an early age thus temporarily stunts the mammary glands. ^Mien the animal is refed the glands respond slowly. WTien the bod}' weight during refeeding reaches that of a normal at the age of puberty, the milk-ducts are far behind those of the normal rat at corresponding body weight. That this stunting is not permanent is shown by the fact that the ducts ultimately attain the same stage of development as those of a normal animal, but at a much later period.
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36. Studies on the mammary gland. VII. The distribution of the subcutaneous fat and its relation to the developing mammary glands in male and female albino rats from birth to ten weeks of age. Jay A. Myers and Fraxk J. Myers, University of Minnesota. In one series of rats the epidermis and corium were removed, care being taken to leave all the subcutaneous fat on the body. The carcasses were then placed in sudan III, scarlet red, or 1 per cent osmic acid. The subcutaneous fat became beautifully differentiated from the surrounding tissues. In another series of rats care was taken to remove all the subcutaneous fat with the skins which were placed in one of the above-mentioned stains and later cleared in glycerin.
 +
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The subcutaneous fat is not deposited unifornil}' over the body, but tends to accumulate m pads in the regions which the ducts of the mam
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160 AMERICAN ASSOCIATION OF ANATOMISTS
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man' glands already or will later occupy. In the inguinal region there appears on each side a fairly definite pad of fat which is thickest cephalad to the ilium. This has been designated the inguinal fat pad. It extends medially then caudad over the pubis and approaches the anal region. The milk-ducts of the abdominal and inguinal mammary glands ramify in the inguinal fat pad. In the thoracic region a mass of subcutaneous fat is deposited on each side of the body. This thoracic fat pad extends cephalocaudad from the region of the axilla nearly to the costal margin. From the dorsal midline it extends ventrad, but ends a considerable distance from the ventral midline. The cervical fat pad extends over the root of the neck and is connected with the thoracic pad. The milk-ducts of the three thoracic glands ramify in the thoracic and cervical pads of fat.
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37. A comparison of the functional adaptation of the middle-ear region in birds and mammals to barometric fluctuations. A. G. Pohlman, St. Louis University.
 +
 +
It is well known that displacements of the drum membrane in mammals do not give rise to correspondingl}' great movements at the Fenestra vestibule, and the simple columellar apparatus in birds through a system of intrinsic bendings accomplishes the same function. It is difficult to believe either system has a transforming function in relation to sound waves. The drum, in mammals, tends to displace lateralward when muscular tension is relaxed, while in bii'ds muscular relaxation is accompanied by medial drum displacement. A positive pressure in the external auditory canal is resisted only by drum elasticity, while the weight of the medially displacing ossicular chain is held up in part by the M. stapedius. The negative prcssure in the external canal is actively resisted by the M. tensor t.Mnpani and, probably because of the character of the joint surface between IMalleus and Incus, is not accompanied by marked excursion of the Stapes. In birds, positive pressures in the external canal are resisted by the M. tensor tympani which at the same time limits medial displacement of the columellar apparatus against the Fenestra vestibule, while negative pressure is passively resisted through elastic hgaments, columellar form, and the possibility of a shearing off the external auditory canal. Both forms display excellent adaptation to fluctuations in barometric pressure without materially influencing the prcssm-e in the perilymph. The Membrana tympani secundaria may be considered a compensation opening to allow for mass displacements in the periljnnph as a result of movement in the Stapes or columella — a function which it seems to exercise in the Anurans, although located entirely outside of the tympanic cavity.
 +
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38. The mitochondrial content of the principal celU of the central nervous system during hibernation in the woodchuck (Marmota monas). A. T. Rasmussen, University of Minnesota.
 +
 +
Since profound hibernation is attended by such a marked reduction in the activities of many organs, including the nervous system, this
 +
 +
 +
 +
PROCEEDINGS 161
 +
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doi-mant condition natm-ally suggests itself as being of value in connection with attempts to unravel the tangled question of the functional significance of mitochondria.
 +
 +
Ha^-ing found no record of such investigations on the nervous system during lethargy-, it is inteiesting to note that, as far as results' have been obtained in research now in progress on one of the species of American marmots, the mitochondria in the chief cells of the brain and spinal cord show no noticeable variation in number, size, shape, or grouping during hibernation. The following cells have been examined: somatic motor cells from the ventral horn of the spinal cord, visceromotor cells from the lateral horn of the spinal cord, cells of nucleus gi-acilis and of nucleus cimeatus, Pm-kinje cells in the vei-mis of the cerebellum, cells from the nucleus of the superior colHculus, Betz cells from the motor cortex and mitral cells of the oKactory bulb.
 +
 +
The conclusions are based upon a series of fifteen adult animals, five of which were sacrificed before hibernation commenced, five toward the end of the dormant period, and five at various intervals after waking up and becoming active.
 +
 +
The woik is being extended to other nerve cells and to the entire glandular system.
 +
 +
39. Experimental inhibition of neural concrescence and some conditions residting. Fraxklix P. Reagax, Piinceton Univei-sity and the University of Illinois IMedical School.
 +
 +
Careful desiccation of the A-itelline membrane of the chick embryo senses to stiffen that structure. If this desiccation be carried out at a . time prior to neural concrescence, the neural tissue adheres to the membrane, rendered powerless to form folds. Usually the brain tissue back to the midbrain becomes tubular. Caudad to this as far as the peh-ic region the nem-al tissue often remains flat, flanked on either side by feather-geiTQs after those structm-es have appeared in development. The roots of the spinal nerves course dorsoventrally. ^^Tiat would ordinarily be vertebral column remains as flat layer of skeletal tissue, ventral to the nem-al tissue and lateralh^ coextensive therewith. Dorsal commissures are of course eliminated. Oedematous condition ventral to the neural tissue is generallj- attended by unusually numerous hTnphatics. In many cases the anterior brain tissue is thrown into many folds and pouches which may be strikingly s^-m metrical. In the diencephahc folds diminutive retinae have been located, far removed from body-wall ectoderm which has failed to produce lenses. Such embrj^os can be reared to stages where interesting results by direct stimiilation might well be obtained.
 +
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40. Muscle and fascia. Robert Retzer, University of Pittsburgh.
 +
 +
A muscle whose fibers are arranged parallel to its long axis is weaker than a muscle of the same volume whose fibers are arranged at an angle to its long axis. The former contains longer fibers which permit of a greater degreee of contraction, and it is found that a muscle of this
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162 AMERICAN ASSOCIATION OF ANATOMISTS
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group always is insiM-ted where it ma}' have advantageous leverage to coinponsatc for its weakness. Reverse holds for group whose fibers are arranged at an angle. The greater the angle the less is extent of contraction and with volume as a constant the stronger the muscle. It is inserted where leverage is disadvantageous.
 +
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Coarseness or fineness of muscle fasciculi have nothing to do with comparative strength of muscle. A muscle that has coarse fibers invariabh' has more than one function. The coarser the fibers the more widely divergent are these functions. AVith these muscles there is no action possible that would allow all the constituent fasciculi to contract simultaneously and to the same degree. Whenever contraction and relaxation in a muscle occur at the same time and to the same degree, the muscles are fine fibered.
 +
 +
The coarseness or fineness of fasciculi is dependent upon the amount of fascia interposed between the fasciculi. Fascia is developed to prevent friction between the muscle fasciculi. Muscles are divided into morphological entities not by the nerves which innervate them, but by the function thej^ perform. The more divergent these functions are, the more fascia is interposed between the muscles.
 +
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Jfl. Laws governing the 'pathways of 'peripheral 'nerves. Robert Retzer,
 +
 +
University of Pittsburgh.
 +
 +
A ph3'siologic explanation that is pui'ely theoretical and without experimental evidence is suggested to explain the following laws which are found to be true for the peripheral nervous system :
 +
 +
Law 1 . Any nerve innervating a given muscle is in part of its course in contiguity with the nerves that supply all the other muscles necessary for the proper performance of the function of that muscle.
 +
 +
Law 2. In automatic coordinate movements, all muscles which must act first in a given movement are innervated first, i.e., they have shorter nerves.
 +
 +
Law 3. All nerves whose activity is necessary for the coordinate performance of a given movement are enclosed, for a part of their course, in a sheath, and the longer the ensheathment the more constant is the coordination of these nerves.
 +
 +
Law 4. All peripheral nerves are contiguous in part of their course with at least another peripheral nerve. The greater the number of nerves with which a given nerve is in contiguity the greater is the complexity or extent of the coordination of the areas supplied by these nerves.
 +
 +
Law 5. Every motor nerve is ensheathed, for a part of its course, with a longer sensory nerve.
 +
 +
Law 6. The same trunks of nerves, whose branches supply the groups of muscles moving a joint, furnish also a distribution of nerves to the skin over the insertions of the same muscles, and the interior of the joint receives its nerves from the same somce. (Hilton.)
 +
 +
 +
 +
PROCEEDINGS 163
 +
 +
42. Soine 'peculiarities of the growth of the human uterus. Richard E. ScAMMOx, University of Minnesota.
 +
 +
A study of a considerable series of measurements of the length of the uterus shows that the organ passes through several phases of growth which are not observed in the other organs of the body. During fetal life the gi'owth of the uterus is not markedly different from that of most of the other fetal organs, but immediately after birth it loses nearly one-third of its natal length. This loss in length, which has been pre\aously described b}' other authors, is completed before the end of the first trimester. From this time until about six years there is little change in length. At about six years there is a short period of growth during which the organ increases about 20 per cent in length. This growth period is followed by a second period of quiescence which continues, on the average, until about the eleventh year. The pubertal growth period is \qy\ variable, but it is usualh' both earher and shorter than is generally assumed. Statistical studies indicate that, in the majority of cases at least, most if not all of the so-called pubertal growth takes place before the menarchy. An examination of the available data on the weight of the uterus indicates that the changes of the organ in weight are much the same as the changes in length except that there is some increases in the weight of the organ throughout the latter part of childhood. The relative weight of the uterus is quite variable, but it e\ddently decreases throughout early postnatal life. (Lantern.)
 +
 +
43. Developmental rate and the perfection of structure. Charles R. Stockard. Cornell University ^Medical School.
 +
 +
Variation in the direction of increased developmental rate is more limited and more difficult to experimentally bring about than is variation toward a decreased or slower rate.
 +
 +
The acceleration of developmental rate that may be induced in earh- embryos tends to increase the perfection of the resulting indi\adual. The ideal rate of development is probably somewhat faster than the average generally followed.
 +
 +
The limits of retardation in the rate of development are extremely wide. Development maj' be slowed down to almost zero or apparently stopped for long or short periods of time without noticeably injuring the embryos of many species. However, when the rate of development is retarded, but not entirel}' stopped, at certain critical periods and development is allowed to proceed at the diminished rate for some time, most serious structural anomalies are induced."
 +
 +
Double monsters very hkely result from a slowing down of the rate at a time when the primary embryonic bud should arise. Normally, the initial appearance of the primarj' embryonic bud probably suppresses other buds which potentially exist. The distance apart of two buds on the blastodisc determines the degree of doubleness of the resulting individual. Unless the two buds arise almost simultaneously, they are unequal in their later developmental rates and structural conditions. WTien one bud obtains the start, this start constitutes a
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164 AMERICAN ASSOCIATION OF ANATOMISTS
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supremacy which aknost invariably allows the leading bud to develop into a perfectl}^ normal specimen, and invariably defeats the possibility of normal development on the part of the slower bud.
 +
 +
J^. A very young monozygotic twin. George L. Streeter, Department of Embryology, Carnegie Institution.
 +
 +
The specimen reported consists of an amniotic vesicle 0.1 mm. in its largest diameter, with a detached yolk-vesicle 0.03 mm. in diameter. The amniotic vesicle is spherical in form and possesses an ectodermic wall the embryonic and amniotic portions of which can be clearly distinguished. The two vesicles are enmeshed in the loose mesenchj-me in the region of the body-stalk of the co-twin. The latter is a well-preserved, normal embryo in the primitive-groove stage, having an embryonic plate 0.92 mm. long, 0.78 mm. wide. The greatest external diameter of the chorion enclosing the two embryos is 9 mm. The relation of the smaller twin to the larger is of the character that would be expected when the primary embryonic mass within the chorionic ectoderm had undergone di\'ision into the primordia of the two embiyos, and the specimen thus tends to substantiate that theory of the origin of such twins.
 +
 +
45. On the behavior of the mammary epithelial cell towards vital dyes in various functional epochs of its life cycle. Monroe Sutter, University of California.
 +
 +
Various researches in this laboratory have in the last few years been directed towards the solution of the phenomena of vital staining with dyes of the acid azo class. These substances can be said to demonstrate in a spectacnlar way the power of specific cells and tissues to ingest, store, and concentrate material which is in an analogous ph5sical and chemical state with such dye solutions. This conclusion would appear to mark an advance in our understanding of the ' vital staining' reaction, for theories of the staining of living protoplasm by virtue of unknown specific chemical or physical combinations have hitherto dominated the field. The vital azo dyes demonstrate the capacity- of cells to be penetrated and to segregate within their protoplasm, accumulations of such substances.
 +
 +
In particular, the differing reaction of various closely related cells to these tests has received attention in this laboratory. There has also been undertaken a comparative study of the vital dye reaction displayed under various experimental conditions by the same cell type. This histophysiological agent has thus given us proof of very significant changes in the behavior of the same cell type when submitted to various experimental conditions. In some instances we are able to clearly relate these to impaired vitality of the cells.
 +
 +
The following communication deals with the mammary gland in the rat. Certain of the vital acid dyes are always deposited in some few of the epithelial tissues, though such phenomena constitute exceptions to the rather rigid rule of the 'exclusion of the epithelia from
 +
 +
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 +
PROCEEDINGS
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165
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participation in the 'vital staining' effect. The hepatic parenchyma, adrenal cortical glomerulosa, glandular pituitary, renal tubular, ovarian luteal, and the mammary epithelia are to be mentioned here. ^Nlany dyes of the acid azo series are deposited to some extent in the mammary epithehal cell. On the administration of some of these dyes, however, the actively functioning mammary epitheUum refuses to store the dyestuff, even though it does so when the gland is in a resting condition. In such cases, impairment and regression of the gland produced by cessation of suckling promptly leads to a different behavior on the part of these cells. They now accumulate large vital dye 'deposits.' This is the case with the blue dye produced from the diazotization of ortho toluidine and its linkage with a molecule each of chromotrope and the Nevile-Winther acids. ^
 +
 +
 +
 +
OH
 +
 +
 +
 +
OH OH
 +
 +
 +
 +
-N = N
 +
 +
 +
 +
 +
'— SO3N
 +
 +
 +
 +
3->2
 +
 +
 +
 +
SOsNa
 +
 +
Unlike the above dye, trypan-blue produces cellular deposits in the resting, the developing, and the actively functioning mammaiy epithelial cells, but the number of the dye 'granules' is greatly increased during regression. Wieszeniewski has secured a similar reaction on the part of shghtly injured renal epithelium after clamping momentarily the renal artery.
 +
 +
The production of cytoplasmic dye deposits in even.' mammarj- epithehal cell in this way has demonstrated in an irrefutable manner that each cell maintains its integrity throughout the lactation period, even though the peripheral part of the cytoplasm is discharged en masse in milk elaboration and secretion.
 +
 +
4^. On the experimental productioyi of edema hy nephrectomy.'^ W. W.
 +
 +
SwixGLE (introduced by C. F. W. ]^IcClm-e), Princeton University.
 +
 +
These experiments were performed in order to test the view recently advanced by C. F. W. AlcClure (Jour. Gen. Physiol., vol. 1, no. 3) that edema may be due to block in kidney function of some sort.
 +
 +
1. The glandular portion of both pronephroi was extirpated from 6-mm. larvae of Rana sylvatica, at about the time when this organ first
 +
 +
iThis dye has been employed by Evans and Long to 'mark' corpora lutea of known age in order to test their survival under various circumstances, and by Corner and Hunri (Amer. Jour. Physiol., vol. 48, 1918) for similar purposes.
 +
 +
'Essentially similar observations have been made by Ruth B. Rowland on the embryos of Amblystoma (Proc. Nat. Acad. Sci., vol. 2, 1916) which the above results confirm. I regret that I was unaware of the ejristence of this paper when my abstract was sent to the press.
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166 AMERICAN ASSOCIATION OF ANATOMISTS
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 +
becomes functional. Twenty-four to thirty hours later the larvae were all edematous — in fact, swollen to such an extent that rupture of the body wall occurred in many.
 +
 +
2. The glandular portion of the pronephros (on one side only) was extirpated in a second set of larvae. Shght edema developed within twent3'-four hours, confined chiefly to the side lacking the kidney. The remaining kidney underwent great hypertrophj-. The larvae all survived. Four days later the edema disappeared, due to the functional development of the mesonephros.
 +
 +
3. The Wolffian ducts of one other set of larvae were severed in the posterior part of body and portions cut out. Edema developed w'ithin twenty-four hours with great distention of the Ijniiph sinuses and body cavity.
 +
 +
4. In another set of 6-mm. larvae, the Wolffian ducts were severed cephalad of the cloacal opening, the tubes dissected anteriorly, and hung outside the larva through the incision in the body wall. The glandular portion of the kidney was left intact. Those larvae which survived the operation for thirty-six hours showed practically no edema. The kidneys functioned normally despite the abnormal position of the ducts.
 +
 +
J^l. The relation of the cartilaginous otic capsule to the facial nerve. R.
 +
 +
J. Terry, Washington University School of Medicine.
 +
 +
The bony skeleton of the ear of mammals is tunneled more or less extensively by the facial nerve in its exit from the cranium. The cartilaginous otic capsule also of mammalian embrj'os is traversed by the facial nerve. Studies of the developnaent of the otic capsule of mammals have brought forth evidence of at least two different elements entering into its composition: one, the cartilaginous wall enclosing the epitheUal cochlear canal and semicircular ducts, the other, the suprafacial commissure, probably a parietal derivative. Between these elements is the canal for the facial nerve, in such position that the proper otic capsule is posterior, the suprafacial commissure anterior. In the embrj^os of reptiles and amphibians the facial nerve passes cephalad of the otic capsule in its exit from the chondrocranium through an opening between the otic capsule and some part of the floor or lateral wall of the skull, that is, a parietal part. This, which is regarded as the primitive relation of the facial nerve to the otic capsule, is masked in adult amphibians, reptiles, and mammals first by fusion of the parietal element with the otic capsule and later by ossification.
 +
 +
48. The structure of the clasmatocyte. Harry W. Vance (introduced
 +
 +
by W. H. Lewis), Johns Hopkins Medical School.
 +
 +
Clasmatocytes are abundant in cultures of subcutaneous tissue, and in fixed specimens some of them are flattened out on the under surface of the coverslips in such a manner as to enable careful studies to be made of their structure. The .most striking features are the large centrosphere, the large vacuoles, and the eccentrically placed nucleus.
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 +
PKOCEEDINGS 167
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 +
The large finely granular centrosphere occupies, in most of the flattened cells, approximately the center of the cell. At the center of this centrosphere is often seen a single or double centriole. The centriole when \-isible is always separated from the nucleus by a distance equal to or greater than the radius of the centrosphere, and this distance may be greater than the short or even long chameter of the nucleus. The fine granules of the centrosphere in the specimens so far studied come close up to the centriole, when the latter is \4sible. The periphery^ of, the centrosphere is continued into the cytoplasmic framework, lying between the vacuoles which otherwise fill up the peripheral regions of the cell. There are often indications of radiations in the centrosphere which seem to continue into the cytoplasmic framework. The nucleus is almost always crowded off to one side of the cell, often touching the edge. In many cases vacuoles separate the centrosphere from the nucleus. The centrosphere with its centriole thus seems to be the center of acti^^ty, the dynamic center of the cell according to Boveri.
 +
 +
49. The effect of intravenous injections of various concentration upon the central nervous system. Lewis H. Weed, Capt., ^I.C, and Paul S. ^IcKiBBEX. 1st Lt., San. C, Amiy Neuro-Surgical Laboratory', Johns Hopkins ^ledical School.
 +
 +
The intravenous injection of solutions of various concentrations have been found to alter markedly the pressure of the cerebrospinal fluid. Strongly h^-pertonic solutions of the common sodium salts (chloride, sulphate, bicarbonate) or of glucose, on intravenous administration, give an initial rise in the pressure of the cerebrospinal fluid followed b}- a profound and enduring fall, frequently to below zero. Similar injections of hypotonic solutions (distilled water) cause a marked and persisting rise in the pressure of the fluid. Ringer's solution, in control isotonic injections, alters the pressure of the fluid only during the period of introduction; the pressure quickly returns to its former level.
 +
 +
The brains of animals receiving injections of the hypotonic or hypertonic solutions are considerably changed in volmne. The brain of the animal given an intravenous injection of Ringer's solution is not abnormal. After the intravenous injection of the concentrated salt solution, the brain becomes shrunken, the gyri more rounded, and the sulci widened. The intravenous injection of water causes marked swelling of the brain, flattening of convolutions, and obliteration of sulci. If these changes are brought about in a trephined skull, with opened dtua, the brain of the animal receiving water protrudes in a marked herniation, while with the concentrated salt a tremendous shrinkage of the brain away from the skull is noted. With Ringer's solution, in such experiments, the brain maintains a gentle convexity in the trephine opening.
 +
 +
Such alterations in brain bulk are independent of vascular changes and persist after formalin fixation,
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THE AXATOMICAL BECORD, VOL. 16, NO. 3
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168 AMERICAN ASSOCIATION OF ANATOMISTS
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50. Influence of the ovaries upon the production of artificial deciduomata;
 +
 +
confirmatory studies. George W, Corner and Stafford L. Warren, University of California.
 +
 +
One of the few recent clues toward solving; the perplexities of interaction between uterus and ovaries was given in 1907 and 1908 by Leo Loeb. in his discovery that at certain stages of the reproductive cycle of the female guinea-pig, injury to the uterine mucosa leads to the formation of a tumor at the site of trauma which closely resembles in cellular structure the maternal portion of the placenta.
 +
 +
This reaction of the endometrium can be elicited only during a limited time, from two to nine days after ovulation; it does not occur in the absence of the ovaries, even if these be left in place until after ovulation has occurred. From these facts Loeb believes that the young corpus luteum fonned at the time of ovulation develops a hormone which in some way sensitizes the uterine mucosa in time to receive the ovum and to participate in placenta formation. The artificial stimulus of his experiment merely imitates the trophic action of the early embryonic ectoblast.
 +
 +
Evidence confirming these statements has been brought forward by Robert Frank ('11), using rats. In view of the importance of the subject and the increasing use of this species in the laboratorj^, it seems worth while to add the results of further studies with rats.
 +
 +
Pregnant animals were selected from a colony of albino rats (Mus norvegicus) shghtly admixed with brown strains. They were allowed to give birth, in order to fix the date of ovulation, which invariably occurs within twenty-four hours after parturition. Seven to eight days after parturition (therefore, six to seven days after ovulation), the abdomen was opened under ether anaesthesia and the uterus traumatized by the insertion of a small foreign body, such as a fine short piece of glass, into the lumen; by the passage of a silk suture through the uterine wall, or merelj^ by scratching the mucosa with a needle inserted through the wall.
 +
 +
In seven successive animals treated in this way, and then killed four or five days after operation, the traumatized areas were found to present large soft solid enlargements of dark congested appearance, in greatest diameter more than twice as thick as the intervening parts of the uterus. In color and texture the tumors greatly resembled the enlargements of early pregnancy in the rat. Microscopic sections through them showed the uterine mucosa to have been replaced by a sohd mass of cells varying from spindle-shaped to large oval outline. Many nuclei were in mitosis; an occasional cell was polynuclear. In some specimens small local areas of degeneration were seen. Even when the traumatizing object, suture thread or glass, had been left in place, the microscope showed that we were not dealing with the famihar foreignbody reaction of tissues in general, but with the production of true decidual cells.
 +
 +
Seven other rats were treated in exactly the same way, except that after waiting from twenty-four to forty-eight hours after parturition
 +
 +
 +
 +
PROCEEDINGS 169
 +
 +
(to permit ovulation) the ovaries were removed. On the seventh or eighth day the uteri were traumatized, and four or five days after the second operation the rats were killed. In none of these animals did any enlargement at the site of trauma take place.
 +
 +
In two animals the ovaries were merely separated from the uterus by cutting between ligatures placed near the tubal extremities of the uterine horns. In these experiments the placenta-hke tumors developed, showing that the influence of the ovaries is exerted through the bloodstream or possibly the nervous system.
 +
 +
Recent determination of the o\'ulation cycle of the white rat by Long and Evans ('19) shows that this animal is not altogether suitable for testing the whole of Loeb's hypothesis, since oestrus and o^Tilation recur at periods of four to eleven days in different individuals (usually five days), while corpora lutea persist at least eight weeks before degeneration. Thus it would seem that the uterus must be almost constantly subject to the influence of the ovaries, and that an attempt to relate the phenomenon of deciduoma formation to the definite stages of the corpus luteum would be hopeless with this species. Our few experiments with time intervals differing from those given above as the optima gave varying results, as might have been expected.
 +
 +
It was hoped that it might be possible to ehcit deciduomata in rats deprived of their ovaries inmaediately after o^'ulation if earh' corpus luteiun tissue from another species were provided. Recent observations of one of the present authors (Corner, '19) upon the development of the corpus luteum of the sow, permitted the collection of a plentiful amount of tissue from the first week after o^nilation, but its administration to a small series of rats, by mouth in the fresh state, by abdominal injection after desiccation, or in alcohoUc extract, has so far given negative results.
 +
 +
51. Sidelights from early abnormal conceptuses. A. W. Meyer, Stanford University.
 +
 +
An examination of some early human conceptuses suggests that the amnion is formed b}' ca\'itation as assumed, and that the chorionic and umbiUcal vesicles at least have some power of independent unassociated growth.
 +
 +
Early death of the embryo apparently sometimes is due to failm'e of proper rotation of the chorionic vesicle, in consequences of wliich the belly stalk becomes located opposite the reflexa. Hence the eccentric forms of insertion of the umbilical cord may in part at least be due to faulty orientation on part of the implanting conceptus.
 +
 +
The presence of undoubted isolated vascular rudiments in the viUi of some young specimens also would seem to suggest that the development of \'illous vessels is not necessarily wholly centrifugal nor dependent entirely upon the vascularization of the embryo itself. This conclusion would seem to be unavoidable even if one could assume that normal and abnormal development foUow fundamentally different plans.
 +
 +
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170 AMERICAN ASSOCIATION OF ANATOMISTS
 +
 +
Although the occurrence of pathologic, or at least of abnormal, unfertilized ova within the ovaries is not at all unlikely, the lack of directly confirmatory evidence emphasizes not only the need of further study of these organs, but especially the critical examination of both earh' abnormal and apparently normal conceptuses. Since early embr\'os usually are obtained from abortuses it would perhaps be safer to assume that many of these are not wholly normal in form and should be regarded with suspicion
 +
 +
 +
 +
1. Eosinophilic myelocytes and basophilic cells in the thymus of postil pigs. J. A. Badertscher, Indiana University.
 +
 +
 +
 +
£. Series of hind limbs of pig embryos showing the genesis of bone, muscle, and joints. Eben J. Carey, Creighton Medical College.
 +
 +
3. Ho7ids of polydactyl negro twins. C. H. Danforth, Washington University School of Medicine.
 +
 +
Photographs and drawings showing points of similarity and difference in the anatomy of the hands from a pair of negro infants.
 +
 +
4. A S^mm. human embryo. C. L. Davis, George Washington University Medical School.
 +
 +
5. Sections of Crepidula plana showing different developmental stages of the gonad. Harley N. Gould (introduced by Dr. Robert Retzer), University of Pittsburgh.
 +
 +
6. Sections of guinea-pig cochleae showing the normal and the lesions produced by detonations. Stacy R. Guild, University of Michigan.
 +
 +
7. A . Models of the digestive system, heart, and the jugular lymph sac of the 7-mm. opossum embryo. B. Dissections and stereophotographs of opossum embryos. Chester H. Heuser, The Wistar Institute of Anatom3^
 +
 +
For each embryo the j&nal stage of the dissection was planned in advance, but for records and future study numerous sets of stereophotographs were made during the progress of the work. Details in the photographs are much better seen if enlargerhents be made in the form of transparencies. Also instructive views of topographic relations can be obtained by preparing 'ghost' pictures from two pairs of negatives. This requires double exposures and the registry must be accurate, or similar effects can be had by making the left positive from one set of negatives and the right from another.
 +
 +
8. Thyreoid and hypophysis transplants in Amphibia. E. R. Hoskins and M. M. Hoskins, University of Pittsburgh.
 +
 +
 +
 +
PROCEEDINGS 171
 +
 +
9. A human embryo with 2-3 somites. Slides and drawings. N. William Ixgalls, Western Reserve University, ' Embryo no. 1878 of the Carnegie Collection has a length of 1.38
 +
 +
mm. and a well-marked dorsal concavity. A short, 0.13 mm., primitive streak, traces of dorsal opening of archenteric canal, and small, plug-like cloacal membrane are present. Indications of first branchial cleft; well-defined, hollow thyroid. Open neural tube, early optic pits, otic plates, and ganghon crest of N. V. Three somites are indicated on left side, two on right; anterior and posterior hmits uncertain. Long, distally dilated allantois, amniotic duct. Blood-vessel formation in body-stalk, yolk-sac, and embryo; vascular connections of these areas verj^ attenuated if not wanting. Continuity of vitelUne plexus and omphalomesenteric veins in embryo doubtful. Union of these latter veins to form plexiform, not yet entirely pervious heart, separating again soon to form open, endothelial lined, plexiform ventral aortae and first arches. Wide space between heart and myoepicardial mantle, bridged by numerous, fine, regularly dispersed protoplasmic fibrillae. Beginning differentiation in form of mantle, early stage of dorsal recesses of pericardial coelom. Dorsal aortae not completely formed, nor patent throughout, terminating caudally in single vitelline (umbiHcal) artery which forms (right side) a very slender connection with posterior part of vitelline plexus, left side uncertain. Vessels in bodystalk large and numerous, only small connection with chorionic vessels; connections with vitelline plexus indirect and ill-defined. Short left umbilical vein, entirely unconnected with other vascular anlagen, in somatopleure at junction with amnion. Throughout, various stages in vasculogenesis.
 +
 +
10. a. Microscopic preparations of wing muscle of wasp, fly, mantis, and elater. b. Intercalated discs in human leg muscle. H. E. Jordax, University of Virginia.
 +
 +
11. Models of the Herzog embryos. Frederic T. Lewis, Harvard Medical School.
 +
 +
12. The centriole and centrosphere in degenerating fibroblasts. Warren H. Lewis, Johns Hopkins Medical School.
 +
 +
13. Vital staining of aseptic brain wounds. C. C. Macklin, University of Pittsburgh.
 +
 +
14- Wax reconstructions (Born) of the pronephros in oedematous frog larvae. C. F. W. McClure, Princeton University.
 +
 +
15. Model and drawings showing fate of gill-arch derivatives on the humanbody. Matthew Marshall (introduced by Doctor Retzer), University of Pittsburgh.
 +
 +
 +
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172 AMERICAN ASSOCIATION OF ANATOMISTS
 +
 +
16. A. Slides: 1. Permanent centrosomes connected by intercellular bridges formed from astral rays. 2. Constant and -permanent centrosomes in nerve cells. 3. The centrosome as a secreting organ. 4- Ceils with centrosome dividing without formation of spindle by amitotic karyokinesis. B. Plates: Twenty plates ivith 250 figures, showing centrosomes in tissue and sex cells of all the important classes of animals. J. P. MuNSON, Ellensburg, Washington.
 +
 +
17. Monozygotic twin lambs. Craniopagus. B. D. Myers, Indiana Universit}^ School of Medicine.
 +
 +
18. The effects of inanition on the developing mammary glands in male and female albino rats from birth to ten weeks of age {cleared preparations and stained sectiotis). J. A. Myers, University of Minnesota.
 +
 +
19. The distribution of subcutaneous fat in male and female albino rots from birth to ten iceeks of age {stained and cleared preparations). J. A. Myers and Frank J. Myers, University of Minnesota.
 +
 +
20. A. Graphic charting of anomalies in pig series, a. Right subclavian artery from the aorta descendens and defect in the aortic-pulmonary valve, b. Persistent of symmetrical right and left pulmonary arteries to the lungs. B. Dissection to show the effect of positive and negative pressures in the external auditory canal upon the columella and elastic ligaments of the middle-ear region in Gallus. A. G. PohlMAN, St. Louis University.
 +
 +
21. Manuscript, drawings, and text of the late Professor Sheldon's book on the nervous systern. Robert Retzer, University of Pittsburgh.
 +
 +
22. Cleared preparations and stained sections illustrating the changes in the mammary gland of the albino rat during the second half of pregnancy. F. L. Roberts (introduced by J. A. Myers), University of Minnesota.
 +
 +
23. Graphs illustrating the growth of the human stomach. Richard E. ScAMMON, University of Minnesota.
 +
 +
A series of graphs ilhistrating the changes in the absohite and relative weight, the area of the mucous membrane, and the cubic capacity of the human stomach from early life 'to maturity.
 +
 +
24. A simple mounting for demonstration slides. Richard E. Scammon, University of Minnesota.
 +
 +
A simple mounting card for special or demonstration slides for class use.
 +
 +
25. Graphs illustrating the weight and length of the new-born child in Europe. Richard E. Scammon and Stanley H. Haynes, Unisity of Minnesota.
 +
 +
A scries of graphs and maps illustrating the average weight and length of the new-born child in the various districts in Europe. Graphs
 +
 +
 +
 +
PROCEEDINGS 173
 +
 +
showing the variation in weight and lengths in these same districts. Tables of comparison of the weight and length of new-born European children with the weight and length of new-born Caucasian children in other countries and new-born children of other races.
 +
 +
26. A. Reconstructions of the axial artery of the lower extremity of a 6-mm. human embryo. B. A collection of photographs of anomalies of the arteries of the human lower extremity. H. D, Senior, New York University Medical College.
 +
 +
27. Anatomical drawings. R. ]\I. Strong, Loyola University School of ]\Iedicine.
 +
 +
28. Museum jars of terra-cotta. R. J. Terry, Washington University School of ]\ledicine.
 +
 +
These jars are adapted to specimens which present one surface of interest and which require only slight illumination from above and at the sides. Two forms have been made: 1) a discus for the exliibition of frozen sections and similar large fiat specimens; 2) rectangular jars for the usual objects in anatomical collections. The glass front is secured either by clamps or by cementing, depending upon the size of the jar. The terra-cotta is tinted and by glazing made impervious to fluids. These jars are not expensive, and since the}- can be made at any pottery are easily obtainable. The fact that hght does not enter from the back, as in the case of the glass jar, and strike the eyes of the observer is a distinct advantage.
 +
 +
29. Early human ovum, specimen and drawings. F. ^Y. Thyng, New York University Medical College
 +
 +
30. The structures of the clasmatocyte. Harry W. Yance (introduced by W. H. Lewis), Johns Hopkins ^Medical School.
 +
 +
31. A simple method of injecting blood-vessels so as to reveal them in Roentgenograms. Demonstration of stereoscopic Roentgenograms of the vascular supply of some of the joints. C. R. Bardeen, L'niversity of Wisconsin.
 +
 +
To the alcohol, carbolic acid, glycerine mixture now in common use for preserving cadavers, barium sulphate maj' be added and the mixture injected in the usual way. If the mixture with barium sulphate is not too thick, the embalming fluid will flow readily throughout the cadaver and diffuse so as to preserve the tissues indefinitely. The barium sulphate remains in the blood-vessels and makes these opaque to the Roentgen rays. If the cadaver is subsequently dissected, the larger vessels should be tied off before cutting them, since the mixture in them remains soft. The barium-sulphate mixture in the smaller vessels causes little difficulty during subsequent dissection.
 +
 +
 +
 +
AMERICAN ASSOCIATION OF ANATOMISTS
 +
 +
OFFICERS AND LIST OF MEMBERS
 +
 +
Officers
 +
 +
President Robert R. Benslet
 +
 +
Vice-President Charles R. Bardeen
 +
 +
Secretary-Treasurer Charles R. Stockard
 +
 +
Executive Committee
 +
 +
For term expiring 1919 Eliot R. Clark, Reuben M. Strong
 +
 +
For term expiring 1920 George L. Streeter, J. Playfair McMurrich
 +
 +
For term expiring 1921 George S. HtTNTixGTON, Harvey E. Jordan
 +
 +
For term expiring 1922 Charles W. M. PoYJfrER, Herbert M. Evans
 +
 +
Delegate to the Council of A.A.A.S. Simon Henry Gage
 +
 +
Committee on Nominations for 1919 J. Playfair McMurrich, Chairman, G. S. Huntington and F. R. Sabin
 +
 +
Honorary Members
 +
 +
S. Ram6n y Cajal Madrid, Spain
 +
 +
John Cleland Glasgow, Scotland
 +
 +
Oscar Hertwig Berlin, Germany
 +
 +
Alexander Macalistbr Cambridge, England
 +
 +
A. Nicolas Paris, France
 +
 +
L. Ranvier Paris, France
 +
 +
Gustav Retzius Stockholm , Stceden
 +
 +
Wilhelm Roux Halle, Germany
 +
 +
Carl Toldt Vienna, Austria
 +
 +
Wilhelm von Waldeyer Berlin, Germany
 +
 +
Members
 +
 +
Addison, William Henry Fitzgerald, B.A., M.D., Assistant Professor of Normal
 +
 +
Histology and Embryology, University of Pennsylvania, Philadelphia, Pa. Allen, Bennet Mills, Ph.D., Professor of Zoology, University of Kansas, 16BS
 +
 +
Indiana Street, Lawrence, Kans. Allen, Ezra, A.M., Ph.D., Professor of Biology, Philadelphia School of Pedagogy,
 +
 +
125 Thompson Ave., Ardmore, Pa. Allen, William F., A.M., Ph.D., Professor of Anatomy, University of Oregon
 +
 +
Medical School, Portland, Oregon.
 +
 +
175
 +
 +
 +
 +
176 AMERICAN ASSOCIATION OF ANATOMISTS
 +
 +
Allis, Edward Phelps, Jr.. M.D.. LL.D., Palais dc Carnoles, Mentone (A.M.) France.
 +
 +
Amsbaugh, A. E., A.B., M.D., LcUennan General Hospital, San Francisco, Calif.
 +
 +
Appleby, J. I., A.B., Graduate Assistant in Anatomy, Anatomical InstittUe, University of Minnesota, Minneapolis, Minn.
 +
 +
Arey, Leslie B., Ph.D., Associate Professor of Anatomy, Northwestern University Medical School, 2^21 Dearborn Street, Chicago, III.
 +
 +
Atwell, Wayne Jasox, A.M., Ph.D., Professor of Anatomy, University of Buffalo Medical College, 24 High St., Buffalo, N. Y.
 +
 +
Badertscher, Jacob A., Ph.M.. Ph.D.. Associate Professor of Anatomy, Indiana University School of Medicine, 312 South Fe.s.s Avenue, Bloomington, Ind.
 +
 +
Bagley, Jr., Charles, M.D., Major M. C, 5 West Chase Street, Baltimore, Md.
 +
 +
Bailey, Percival, M.D., Ph.D., Assistant Resident Surgeon, Peter Bent Brigham Hospital, 721 Huntington Ave., Boston, Mass.
 +
 +
Baitsell, George Alfred, Ph.D., M.A., Assistant Professor of Biology, Yale University', Osborne Zoological Laboratory, Neic Haven, Conn.
 +
 +
Baker, Wilmer, M.D., Assistant Professor of Anatomy, University of Virginia, University, Virginia.
 +
 +
B.\hvvn.N, Wesley Manning, A.M., M.D., Professor of Anatomy, Albany Medical College, Albany, N. Y.
 +
 +
Bardeen, Charles Russell, A.B., M.D. (Ex. Com. '06-09, Vice-President '18-), Professor of Anatomy and Dean of Medical School, University of Wisconsin, Science Hall, Madison, Wis.
 +
 +
Bartelmez, George W., Ph.D., Associate Professor of Anatomy, University of Chicago, Chicago, III.
 +
 +
Bates, George Andrew, M.S., D.M.D., Professor of Histology and Embryology, Tufts College Medical School, 4i6 Huntington Avenue, Boston, Mass.
 +
 +
Batson, O. v., A.B., M.D., 738 Rock Creek Church Road, Washington, D. C.
 +
 +
Baumgartner, Edwin A., Ph.D. M.D., Associate in Anatomy, Washington University Medical School, St. Louis, Mo.
 +
 +
Baumgartner, William J., A.M., Associate Professor of Zoology, University of Kansas, Lawrence, Kans.
 +
 +
Bayon, Henry, B.A., M.D., Professor of Applied Anatomy, Tulane University, 2212 Napoleon Avenue, New Orleans, La.
 +
 +
Bean, Robert Bennett, B.S., M.D., Professor of Anatomy, University of Virginia, Preston Heights. Univer.sity, Va.
 +
 +
Beck, Claude S., A.B., Medical Student, Johns Hopkins Medical School, Baltimore, Maryland.
 +
 +
Begg, Alexander S., M.D., Instructor in Anatomy, Harvard Medical School, Boston, Mass.
 +
 +
Bensley, Robert Russell, A.B., M.B., (Second Vice-Pres. '06- '07, Ex. Com. '08-'12, President '18-), Professor of Anatomy, University of Chicago, Chicago, III.
 +
 +
Bevan, Arthur Dean, M.D. (Ex. Com. '96-98), Professor of Surgery, University of Chicago, 2917 Michigari Avenue, Chicago, III.
 +
 +
Bigelow, Robert P., Ph.D., Associate Professor of Zoology and Parasitology, Massachusetts Institute of Technology, Cambridge, Mass.
 +
 +
 +
 +
MEMBERS 177
 +
 +
Black, Davidson, B.A., M.B., Professor of Xeurology and Embryology, Peking Union Medical College, Peking, China.
 +
 +
Blaisdell, Frank Ellsworth, Sr., M.D., Assistant Professor of Surgery, Medical Department of Stanford University, 1520 Lake Street, San Francisco, Calif.
 +
 +
Blake, J. A., A.B., Ph.B., M.A., M.D., Hotel Plaza, 59th St., New York, N. Y.
 +
 +
Bonnet, Charles \V., A.B., M.D., Demonstrator in Anatomy, Jefferson Medical College, Philadelphia, Pa.
 +
 +
Botden, Edward Allen, A.M., Ph.D., Instructor of Comparative Anatomy, Harvard Medical School, Boston, Mass.
 +
 +
Bremer, John Lewis, A.B., M.D., (Ex. Com. '15-'18), Associate Professor of Histology and Director of Anatomical Laboratory, Harvard Medical School, Boston, Mass.
 +
 +
Broadnax, John W., Ph.G., M.D., Associate Professor of Anatomy, Medical College of Virginia, Richmond, Va.
 +
 +
Brookover, Charles, M.S., Ph.D., Professor of Anatomy, Histology and Embryology, University of Louisville, Medical Department, 101 W. Chestnut Street, Louisville, Ky.
 +
 +
Brooks, William Allen, A.M., ^LD., 167 Beacon Street, Boston, Mass.
 +
 +
Brown, A. J., A.B., M.D., Professor of Surgery, Creighton University, College of Medicine, Blackstone Hotel, Omaha, Neb.
 +
 +
Browning, William, Ph.D., M.D., Professor of Neurology, Long Island College Hospital, 54 Lefferts Place, Brooklyn, N. Y.
 +
 +
Bryce, Thomas H., M.A., M.D., Professor of Anatomy, University of Glasgow, No. 2, The University, Glasgow, Scotland.
 +
 +
BuLLARD, H. Hays, A.M., Ph.D., M.D., Associate in Pathology and Resident Pathologist, Johns Hopkins Hospital, Baltimore, Md.
 +
 +
Bunting, Charles Henry, B.S., M.D., Professor of Pathology, University of Wisconsin, Madison, Wis.
 +
 +
Burr, Harold Saxton, Ph.D., Instructor in Anatomy, School of Medicine, Yale University, 150 York Street, New Haven, Conn.
 +
 +
Burrows, Montrose T., A.B., M.D., Assistant Professor of Pathology, Washington University Medical School, St. Louis, Mo.
 +
 +
Byrnes, Charles ^I., B.S., M.D., Associate in Clinical Neurology, Johns Hopkins Medical School, 207 East Preston Street, Baltimore, Md.
 +
 +
Cameron, John, M.D., D.Sc, F.R.S.E., Professor of Anatomy, Dalhousie Medical College, Halifax, Nova Scotia.
 +
 +
Campbell, William Francis, A.B., M.D., Professor of Anatomy and Histology, Long Island College Hospital, 394 Clinton Avenue, Brooklyn, N . Y .
 +
 +
Cardwell, John C, M.D., Professor of Physiology, Long Island College Hospital, Polhemus Memorial Clinic, Brooklyn, N. Y.
 +
 +
Carey, Eben J., M.S., Assistant Professor of Anatomy, Creighton Uriiversity Medical Department, Omaha, N^eb.
 +
 +
Carpenter, Frederick Walton, Ph.D., Professor of Biology, Trinity College, Hartford, Conn.
 +
 +
Carter, James Thornton, D.D.S., Research Worker, Department of Zoology, University College, 1 Hanover Square, London, W., England.
 +
 +
Carver, Gail L., A.B., A.M., Professor of Biology, Mercer University, Macon, Ga.
 +
 +
 +
 +
178 AMERICAN ASSOCIATION OF ANATOMISTS
 +
 +
Casamajor. Louis, A.M., M.D.. Associate Professor of Neurology, Columbia University, 4S7 West 59th Street, New York City.
 +
 +
Cash, J.\mes Robert, A.B., A.M., Student of Medicine, Johns Hopkins Medical School, Baltimore, Md.
 +
 +
Chambers, Robert, Jr., A.M., Ph.D., Instructor in Anatomy, Cornell University Medical College, New York City.
 +
 +
Chapman, W. B., A.B., M.D., Instructor in Anatomy, Washington University Medical School, 4339 Olive Street, St. Louis, Mo.
 +
 +
Cheever, David, A.B., M.D., Assistant Professor of Surgery and Associate in Anatomy, Harvard Medical School, 20 Hereford Street, Boston, A/ass.
 +
 +
Chidester, Floyd E., A.M., Ph.D., Scientific Assistant, U. S. Public Health Service, Newport News, Va.
 +
 +
Child, Charles Manxing, Ph.D., Professor of Zoology, University of Chicago, Chicago, III.
 +
 +
Chillingworth, Felix P., M.D., Assistant Professor of Physiology and Pharmacology, Tulane University, New Orleans, La.
 +
 +
Clark, Elbert, B.S., M.D., Assistant Professor of Anatomy, University of Chicago, Chicago, III.
 +
 +
Clark, Eleanor Linton, A.M., Research Worker, Department of Anatomy, University of Missouri, 413 S. 6th Street, Columbia, Mo.
 +
 +
Clark, Eliot R., A.B., M.D., (Ex. Com. '16-), Professor of Anatomy, University of Missouri, 413 S. 6th Street, Columbia, Mo.
 +
 +
CoE, Wesley R., Ph.D., Professor of Biology, Yale University, Osborne Zoological Laboratory, N^ew Haven, Conn.
 +
 +
Coghill, George E., Ph.D., Professor of Anatomy, University of Kansas Medical School, R. F. D. No. 9, Lawrence, Kans.
 +
 +
Cohn, Alfred E., A.B., M.D., Associate Member, Rockefeller Institute for Medical Research, New York, N. Y.
 +
 +
Cohoe, Benson A., A.B., M.B., Associate Professor of Therapeutics, Care Department of Anatomy, University of Pittsburgh. Pittsburgh, Pa.
 +
 +
CoNANT, William Merritt, M.D., Professor of Clinical Surgery, Tufts Medical School, 486 Commonwealth Avenue, Boston, Mass.
 +
 +
CoNEL, Jesse LeRoy, A.M., Ph.D., Instructor in Anatomy, New York University and Bellevue Hospital Medical College, 338 East 26th Street, New York City.
 +
 +
CoNGDON, Edgar Davidson, Ph.D., Assistant Professor of Anatomy, Leland Stanford University, School of Medicine, 330 Coleridge Avenue, Palo Alto, Calif.
 +
 +
CoNKLiN, Edwin Grant, A.M., Ph.D., Sc.D., Professor of Biology, Princeton University, 139 Broadmead Avenue, Princeton, N. J.
 +
 +
CooKMAN, Alfred, A.B., Professor of Agriculture and Biology, Long Beach High School, 1813-4th Avenue, Los Angeles, Calif.
 +
 +
Corner, George W., A.B., M.D., Assistant Professor of Anatomy, Anatomical Laboratory, University of California, Berkeley, Calif.
 +
 +
Corning, H. K., M.D., Professor of Anatomy, University of Bdle, Biindesstr. 17,
 +
 +
Bdle, Switzerland.
 +
 +
CowDRY, Edmund V., Ph.D., Professor of Anatomy, Department of Anatomy, Peking Union Medical College, Peking, China.
 +
 +
Craig, Joseph David, A.M., M.D.. 12 Ten Broeck Street, Albany, N. Y.
 +
 +
 +
 +
MEMBERS 179
 +
 +
Cb.ugie, E. Horxe, A.B., Demonstrator in the Department of Biology, University of Toronto, Toronto, Canada. Crilz, George W., A.M., M.D., LL.D., F.A.C.S., Professor of Surgery, Western
 +
 +
Reserve University, 214 Osborn Building, Cleveland, Ohio. Crosby, Elizabeth Carolixe, Ph.D., Superintendent of Schools, Petersburg,
 +
 +
Mich. CuLLEX, Thomas S., M.B., 20 E. Eager Street, Baltimore, Md. CuiiMixs, Harold, A.B., Instructor in Histology and Embryology, Vanderbilt
 +
 +
University Medical School, Xashville. Tenn. CrxxixGHAM, Robert S., A.M., M.D., 1st Lieut. M. R. C, U. S. A., R. F. D.
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Xo. 4, Anderson, S. C. Curtis, George M., A.M.. Ph.D., Professor of Anatomy and Director of the Anatomical Department, Vanderbilt University Medical School, 1832 W. Adams St., Chicago, III., Dahlgrex, Ulric, A.B., M.S., Professor of Biology, Princeton University, 204
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Guyot Hall, Princeton, N. J. Daxchakoff, Vera, M.D., Assistant Professor of Anatomy, Columbia University, 437 W. 59th Street, New York City. Daxforth, Charles Haskell, A.M., Ph.D., Associate Professor of Anatomy,
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Washington University Medical School, St. Louis, Mo. Darrach, William, A.M., M.D., Lt. Col. M.C., Dean College of Physicians
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and Surgeons, Columbia University, 437 West o9th St., Xew York City. Davis, Carl L., M.D, Professor of Anatomy, George Washington University,
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Washington, D. C. Davis, Da%-id M., B.S., M.D., Instructor in Urology and Pathologist, Brady Urological Institute, Johns Hopkins Hospital, 1312 Eutaiv Place, Baltimore, Md. Dawsox, Aldex B., A.B., Ph.D., Assistant Professor of Microscopical Anatomy,
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Loyola University Medical School, 706 S. Lincoln St., Chicago, III. Deax, Bashford, A.m., Ph.D., Professor of Vertebrate Zoology, Columbia Universit}', Curator of Fishes and Reptiles, American Museum Natural History, Riverdale-on-H itd-son, Xeiv York City. Dettviler, Samuel Raxdall, A.M., Ph.D., In^structor in Anatomy, Yale School
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of Medicine, 150 York Street, Xevc Haven, Conn. Dixox, A. Fraxcis, M.B., Sc.D., University Professor of Anatomy, Trinity
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College, Dublin, Ireland. DoDSox, JoHx MiLTOx, A.M., M.D.. Dean and Professor of Medicine, Rush Medical College, Universitj- of Chicago, 5817 Blackston Avenue, Chicago, III. Dolley, D. H., A.m., M.D., Professor of Patholog\% University of Missouri,
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Columbia, Mo. DoxALDSOx, Hex-ry Herbert, Ph.D., D.Sc. (Ex. Com. '09-'13. Pres. '16-'17), Professor of Neurology, The Wistar Institute of Anatomy and Biology, Woodland Avenue and 36th Street, Philadelphia, Pa. DoxALDSox, JoHX C, Ph.B., M.D., Instructor in Anatomy, University of Cincinnati Medical College, The Mapleuood, Clifton, Cincinnati, Ohio. DowxEY, Hal, A.M., Ph.D., Professor of Histology, Department of Animal Biology, University of Minnesota, Minneapolis, Minn.
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180 AMERICAN ASSOCIATION OF ANATOMISTS
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DuBREUiL, Geokges, ISI.D., Professor of Anatomy, Faculle de MMicine, Place de la Vicloire. Bordeaux, France.
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DuESBERG, Jules, M.D., Professor of Anatomy, Universihj of Liege, Liege, Belgium.
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DuN'N, Elizabeth Hopkins, A.M., M.D., Marine Biological Laboratory, Woods Hole, Mass.
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Eaton, Paul Barnes, A.B., M.D., Instructor Bacteriology, School of Hygiene, Johns Hopkins University, 310 W. Monument Street, Baltimore, Md.
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EccLES, Robert G., M.D., Phar.D., 681 Tenth Street, Brooklyn, N. Y.
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Elwyx. Adolph, A.m., Assistant Professor of Anatomy, Long Island College Hospital; Ass,ociate in Anatomy Columbia University, 520 West 12Uh Street, New York City.
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Emmel, Victor E., M.S., Ph.D., Associate Professor of Anatomy, University of Illinois College of Medicine, Congress and Honore Streets, Chicago, III.
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EssiCK, Charles Rhein, B.A., M.D., 520 Franklin Street, Reading, Pa.
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Evans, Herbert McLean, B.S., M.D., Professor of Anatomy, University of California, Berkeley, Calif.
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Evans, Thomas Horace, M.D., Associate Professor of Anatomy, Long Island College Hospital, Henry and A7mty Streets, Brooklyn, N. Y.
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Evatt. Evelyn John, B.S., M.B., Professor of Anatomy, Royal College of Surgeons, Dublin, Ireland.
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Eycleshymer, Albert Chauncey, Ph.D., M.D., Professor of Anatomy, Medical College, University of Illinois, Honore and Congress Streets, Chicago, III.
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Ferris, Harry Burr, A.B., M.D., Hunt Professor of Anatomy and Head of the Department of Anatomy, Medical Department, Yale University, 395 St. Ronan Street, New Haven, Conn.
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Fetterolf, George, A.B., M.D., Sc.D., Assistant Professor of Anatomy, University of Pennsylv