288 STUDIES ON PATHOLOGIC OVA. 



amniotic fluid, it does not therefore follow that they really remain structurally 

 unchanged. However, I can not confirm the opinion of Herzog (1898) that chori- 

 onic villi degenerate with astonishing rapidity after the death of the embryo, which 

 Herzog claimed was true especially in young placentae. According to Herzog, only 

 the most intimate acquaintance enables one to recognize the villi after the embryo 

 has been dead two or three weeks. Since the villi are usually the last thing to dis- 

 appear and may survive the death of the embryo by months, even in the case of 

 early conceptuses, it is difficult to understand what may have been responsible for 

 Herzog's opinion. Leopold (1882) stated that it has been shown that a bare fetus 

 in the peritoneal cavity will macerate and become disarticulated, but that a fetus 

 surrounded by the intact membranes will become dry and leathery. Just what 

 the basis for this statement is I do not know, but it would seem that compar- 

 atively prompt disarticulation of any except perhaps very young cyemata must 

 imply the presence of putrefactive conditions, for the length of time which dead 

 tissues can survive depends very largely upon the advent of putrefaction. 



Microscopic changes no doubt appear quite promptly after death in all con- 

 ceptuses, but, strange as it may seem, the most pronounced internal changes 

 may sometimes fail to manifest themselves externally. In one instance (No. 962), 

 for example, Mall had noted that the shape of the embryo had been preserved so 

 perfectly that the specimen seemed normal in form. Yet the slightest jar on the 

 containing vessel resulted in its complete disintegration. Apparently this speci- 

 men was somewhat farther advanced than embryo No. 2197 (figure 29, plate 4, 

 Chap. IV). The same thing may be true of the villi, the shape of which may be 

 preserved perfectly, although structurally they may have become mere gossamers, 

 as illustrated by the villi of No. 606, shown in figure 11 (plate 1, Chap. IV). 



Since very few abortuses are expelled promptly, practically all are macerated 

 to a greater or lesser degree. This applies to specimens classed as normal, as well 

 as to those classed as pathologic. Nor can the mere fact that a specimen was 

 obtained in ute.ro at operation assure one that it is not macerated. No. 1224, for 

 example, although obtained at operation, is a very greatly macerated, empty 

 chorionic vesicle which was isolated completely in the uterine cavity. In another 

 specimen (No. 1767), also obtained at hysterectomy, an abscess is found within 

 the implantation site. No. 782, a third specimen of the same kind, and also other 

 hysterectomy specimens, as previously stated, contain young hydatiform vesicles. 

 Although the uterus and conceptus of No. 872 were placed in 10 per cent formalin 

 after operation and kept in a thermostat for two days, the villi nevertheless are 

 markedly macerated. They are also almost wholly non- vascular, remnants of the 

 vessels being present in some of the villi only. The amnion is absent, the fibrous 

 chorion also shows maceration changes, and the decidua is decided^ infiltrated. 

 Hence it is important to remember that unless one is dealing with a normal im- 

 plantation and a wholly normal uterus, the fact that the specimen was obtained 

 at operation and preserved immediately with the best of care is not an absolute 

 guarantee against the presence of early maceration changes. This is illustrated 

 especially well by tubal specimens, which so frequently are embedded or isolated 



