Paper - A study of the causes underlying the origin of human monsters 19
|Embryology - 20 Apr 2021 Expand to Translate|
|Google Translate - select your language from the list shown below (this will open a new external page)|
العربية | català | 中文 | 中國傳統的 | français | Deutsche | עִברִית | हिंदी | bahasa Indonesia | italiano | 日本語 | 한국어 | မြန်မာ | Pilipino | Polskie | português | ਪੰਜਾਬੀ ਦੇ | Română | русский | Español | Swahili | Svensk | ไทย | Türkçe | اردو | ייִדיש | Tiếng Việt These external translations are automated and may not be accurate. (More? About Translations)
Mall FP. A study of the causes underlying the origin of human monsters. (1908) J Morphol. 19: 3-368.
|Historic Disclaimer - information about historic embryology pages|
|Embryology History | Historic Embryology Papers)|
A Study Of The Causes Underlying The Origin Of Human Monsters
Embryos of the Seventh Week
In the seventh week, when some of the bones are ossiﬁed, the embryos have reached a stage in which interference with their nutrition does not shatter all of their tissues at once. The effect upon the central nervous system is still more pronounced than that upon the other tissues, and even at this late period the dissociated structures continued to grow in an irregular fashion.
The number of specimens at this time is also greatly diminished, as is naturally expected, for the younger ova are attacked early by the infected mucous membrane of the uterus and few of them survive until the seventh week. It follows, then, that as gestation continues pathological ova are less and less likely to be found. To be sure, the diseased specimen may be retained in the uterus for a long time as a mole, with or without an embryo, but if the chorion is not affected during the first few months of pregnancy it is likely to go on to full term, or if it is aborted so late it rarely contains a dwarfed embryo. Furthermore, infections of the uterus are infrequent after pregnancy is well under way, and in case it does take place, the probability of its attacking the whole chorion is slight. The embryo would probably withstand the insult, since it is now more differentiated and more resistant.
There are in my collection ten pathological specimens of the seventh week and half of them may be normal, at least the changes in them are but slight. Furthermore, after the seventh week there is but one pathological specimen a week until the fourteenth week, and none from this time until the end of pregnancy.
A summary of the embryos brought together in the various tables is as follows:
|Ova with neither embryo nor amnion||29|
|Ova with amnion but without embryo||15|
|Pathological embryos of the second week||4|
|Pathological embryos of the third week||18|
|Pathological embryos of the fourth week||21|
|Pathological embryos of the fifth week||13|
|Pathological embryos of the sixth week||27|
|Pathological embryos of the seventh week||10|
|Pathological embryos of the eighth week||2|
|Pathological embryos of the ninth week||1|
|Pathological embryos of the tenth week||0|
|Pathological embryos of the eleventh week||1|
|Pathological embryos of the twelfth week||0|
|Pathological embryos of the thirteenth week||1|
|Pathological embryos of the fourteenth week||1|
This infrequency of pathological ova as pregnancy continues is not at all’ remarkable, for human monsters at term are not so very common, and while they are produced in the early months of pregnancy, at ﬁrst the changes in them are slight, and consequently they are not aborted. The pathological ova in which the changes in the embryos are very severe are the kind that are aborted and the ones which I have been considering. However, the reactions in them give us a hint of what takes place in the early stages of monsters that continue to develop until the usual end of pregnancy.
Of the specimens of the seventh week, No. 128 is normal in every respect with the exception of the presence of a fairly marked magma reticulé in the amniotic cavity. This I have not found in other normal specimens, and, since it is the earliest and most constant sign of a diseased embryo, it is worthy of mention. No. 307 is also no doubt normal, although small clumps of leucocytes are found between the villi and at points they are found in the mesoderm of the chorion. Nos. 268 and 338a may be normal, although some tissue changes are seen. These may be due to maceration, for the specimens are not especially well preserved. Dissociation may have begun in No. 345, but it is more or less obscured by the extensive maceration which accompanies it.
Marked pathological changes are found in specimens Nos. 320 and 94. In them changes are found in the chorion, showing that the attack by leucocytes has been very severe. In one (No. 94) there is a great amount of granular magma within the amnion. The tissues of the embryos are disso— ciated, the brain and cord being nearly solid. In general, the boundaries of the organs are obscure, their tissues being more or less infiltrated with round cells. We have in these two embryos conditions found so frequently in younger specimens.
No. 293 is a specimen of unusual interest, for the sections show that most of the embryo is normal, only one portion of it being affected. The blister upon the back was recognized by Dr. Lamb when he opened the chorion. It is filled with a granular albumen, and at its edges burrows into the mesoderm, which is well inﬁltrated with round cells. The “inﬂammatory” process extends along the middle of the back to the top of the head. Immediately over the cord, in the middle of the back, the inﬁltration of cells extends throughout the mesoderm and includes the meninges of the cord, showing a similarity with the changes in the case of spina biﬁda in the embryo described recently by Fischel (Plate I). It certainly would be very easy for a localized affair like this to prepare the way for the production of spina biﬁda. Possibly in the course of time, after my pathological collection contains thousands of specimens, intermediate stages will be found which will show that the changes found in this embryo favor the production of monsters with spina biﬁda.
TABLE XIV. NORMAL EMBRYOS or THE SEVENTH WEEK. '3 I Specimen. Embryo. Chorion. ‘E E 5 2 mm. mm. days No.17 . . . . . . . . .. x8 4ox3ox2o No. 42 . . . . . . . . . . I8 35 No. 160 18 2 mos. No.5 18.5 4ox3o No.28 . . . . . . . .. 19 50 x 30 x.2o 47
No. 229 . . . . . . . . . 19 49
No.128 . . . . . . . .. 2o 5ox43 76
No.22 . . . . . . . . .. 2o 35x3ox3o
No. 240 . . . . . . . .. 20 5o x 40 x 30
N9.194 . . . . . . . .. 21 45x45x45
Mmot . . . . . . . . . . 22 53
His . . . . . . . . . . . . 22 56
No. 57 . . . . . . . . . . 23 30
No. 242 . . . . . . . .. 23 7ox5ox5o
No. 363 . . . . . . . . . 23 66
His. (Wt) . . . . . .. 23 55 x 50
No. 72 . . . . . . . . . . 23 40 x 30
No. 27 . . . . . . . . . . 23 30 65
His (Lp) . . . . . .. 23 55x50
No. 6 . . . . . . . . . .. 24 77
N9. 31 . . . . . . . . .. 24 50 x 30 x 30 68
No 127 . . . . . . . .. 24 6ox45x4o 84
Length of Dimensions of Menstrual
No. Embryo. Chorioni Age. Changes in the Chonon. I 320 18 70 x so x 40 ' Some ﬁbrous. Ovum swollen and :1 fewmasses of 1eucocytes. 338a. I8 45 x45 6’co8wks. Normal. 293 19 3 01' 4 months 345 I9 60 X 50 x 50 94 20 5o x 40 x 30 Atrophic and invaded by leucocytes. 128 20 50x43 76 Normal. 201 2o Fibrous and invaded by leucocytes and syncytium. 307 2o 40 x 40 x 40 Invaded by leucocytes. 268 22 226 24 6011602130
Another embryo in which the spinal canal is broken open behind (No. 226) shows extensive alterations in its tissues. The changes in the chorion indicate that the circulation within the embryo had ceased some time before the abortion. Its mesoderm is ﬁbrous and almost devoid of blood-vessels. Between the amnion and chorion there is a layer of organized blood from the mother, showing that there must have been a rupture some time before the abortion.
The external form of the embryo is interesting, the trunk, extremities and cord being normal in form, while there is a marked defect in the head. Here on the dorsal side the de— structive process has also included the upper part of the spinal cord, producing complete spina biﬁda. The rest of the central nervous system is still intact, but the cerebral vesicles are reduced in size and are exposed to the exterior of the body. The free end of the upper part of the cord is broken quite abruptly, while that of the lower part of the medulla is rounded off, i. e., it appears to have healed over. The larger portion of the cervical cord is missing; it may have escaped through the dorsal opening.
There are marked changes in the tissues of the body, which may be due to maceration rather than dissociation. The connective tissues, including the bone and the vascular system, are well preserved, with more or less round-celled inﬁltration and possibly some fibrous thickening.
A more advanced stage of the conditions found in No. 226 may be seen in No. 201, which in addition has cyclopia. In this specimen there are marked changes within the chorion to account for the degeneration of the embryo. The villi of the chorion are intermingled in irregular order with blood, ﬁbrin and pus, and the mesoderm is ﬁbrous and more or less inﬁltrated with leucocytes and syncytial cells.
The form of the specimen is that of a younger embryo, but the ossiﬁcation centers of the maxilla, mandible, clavicle and humerus are present. The epidermis is nearly complete, thickened at points, but wanting over the top of the head. The mouth and anus are obliterated and the coils of intestine form a single mass, into which the entodermal cells ramify. In form the thoracic region, vascular system and liver are normal, although the cells of the latter are necrotic. Throughout the embryo there is an extreme growth of mesodermal tissue, apparently that of the precartilage being the most active. This newly—formed tissue seems to have invaded the embryonic muscles which are more or less destroyed.
The changes within the central nervous system are extreme, the brain being greatly deformed and separated by a growth of connective tissue from the spinal cord below. The caplike process upon the head contains the medulla and midbrain, which are well dissociated, partly necrotic and partly infiltrated with round cells. On either side of this there are two degenerated cerebral hemispheres which communicate in front of the medulla. The spinal cord begins quite abruptly in the upper cervical region, and ends in a marked ﬁbrous tumor, one—half millimeter in diameter, in the upper lumbar region. In the lumbar and cervical regions the spinal canal is ﬁlled with mesodermal tissue rich in b1ood—vessels. Here. however, spinal nerves are present, showing that the destruction of the spinal cord is of recent date.
The two eyes form a single hour—glass-shaped body, with a double retina, two lenses, a single choroid and a single median optic nerve, which does not reach to the brain. Between this and the ear and tongue there are a variety of structures — muscles and nerves — which are difficult to trace. Some nerves pass to the epidermis and may represent branches of the ﬁfth, and one forms a commissure across the median li11e. At any rate, there has been a great deal of shifting, and it is natural to think that the eyes did likewise, as is the case in the experiments on Fundulus, mentioned above.