52 STUDIES ON PATHOLOGIC OVA. 



cavity in cases which clinically are tubal pregnancies, even if they can not be 

 detected by the most careful inspection of the gross specimen or by microscopic 

 examination of frozen sections of portions of the implantation site. 



Whether or not the surviving elements of a conceptus are villi only depends 

 very largely upon the age of the conceptus and upon the sequence of events respon- 

 sible for its death. Indeed, if the entire conceptus is erupted from its implantation 

 cavity by a sudden severe hemorrhage, it -is very unlikely that the villi will be 

 the surviving elements, unless the conceptus is extremely young. The same thing 

 would be true of a conceptus which a severe general inflammatory process had 

 suddenly detached. For in both of the assumed cases the villi would undoubtedly 

 succumb to the destructive processes earlier than the chorionic membrane, the 

 syncytium, or the trophoblast. If, on the other hand, the infectious process gains 

 entrance into the cavity of the chorionic vesicle itself, the latter and the embryo 

 rapidly disintegrate and are destroyed, while some of the villi may long remain 

 in a state of relatively good preservation. 



From these considerations it is evident that it would be possible to form three 

 other groups of specimens in addition to those composed of villi only those 

 composed of remnants of both trophoblast and syncytium, or of one or the other 

 alone. That such specimens actually occur will become evident in the course of 

 this discussion. At present they are included in group 1. However, it is not for 

 this reason alone that the designation "villi only" does not fully describe the first 

 group in the pathologic division. Three specimens in this group, for example, are 

 hydatiform moles, one of which, No. 323, forms a large, compact mass, a portion 

 of which is shown in section in figure 6. Another is composed largely of blood- 

 clot surrounded by decidua, and still another consists largely of a decidual cast 

 with mere traces of syncytium, trophoblast, and perhaps of portions of one or two 

 villi. Furthermore, since it is practically impossible to examine all specimens in 

 their entirety in a complete microscopic series, there is some possibility that the 

 portions examined may not form an adequate basis for the correct classification 

 of the specimen. Hence, for this reason also some specimens are bound to get into 

 incorrect categories. Nor is it without significance that no provision is made 

 among the normal specimens for a group of villi only. Under the present classifica- 

 tion all of these are placed in the pathologic division. This would seem to imply 

 that normal villi are never aborted alone in uterine pregnancy or found alone in 

 tubal pregnancies or in tubal abortions. Yet material from curettage, or from 

 abortions the result of interference by the patient herself, no doubt may contain 

 none but normal villi. I have seen the question raised nowhere, but it seems 

 doubtful whether, except perhaps in the earliest stages, villi can ever develop 

 wholly normally in a tube. Hence the above objection to the present classification 

 might be waived for tubal but not for uterine specimens. 



Among the possible causes of the destruction of conceptuses, inflammatory 

 conditions, as indicated by infiltration, as a rule seem largely predominant. They 

 existed in the great majority of the uterine specimens, protocols of which are 



