220 STUDIES ON PATHOLOGIC OVA. 



depends very largely upon the preservation of the abortus, and this, as is well 

 known, varies greatly. Finzi (1908) also found that the epithelium may be per- 

 fectly preserved or totally destroyed, and that central degeneration is the most 

 noticeable thing and due to the absence of vessels. 



However, the most striking thing about the epithelium usually is not its 

 thickness, the presence of large masses of trophoblast, or of numerous syncytial 

 buds, but its splendid state of preservation, especially as contrasted with that of 

 the stroma. This is true of all except macerated or degenerate specimens, for the 

 life of the epithelium seems assured as long as there are periodic accessions of fresh 

 blood, which, as the clinical histories illustrate, is usually the case. The stroma, 

 on the other hand, probably not being wholly independent of the contained capil- 

 laries, is deprived very largely of its sustenance during, even if not in consequence 

 of, their degeneration. According to some, hydatiform degeneration of the stroma 

 is the result of an accumulation of nutritive products in consequence of the absence 

 of the vessels. Degeneration of stroma and vessels, however, may result from 

 malnutrition due to poor implantation. Daels (1908 b ) reported that the stroma 

 was densest where the syncytium was thickest, and most rarefied where it was 

 thinnest, but I could not determine such a relationship. 



The epithelium of the villi often was found single-layered without any syncy- 

 tium whatever, or with at most a few syncytial buds. Nevertheless, both the 

 syncytium and trophoblast very often show evidences of a marked activity not 

 confined to implanted villi or to the epithelium of the villi as a whole, but which 

 extended to that of the chorionic membrane as well. Surprisingly long, complex, 

 syncytial buds, whorls, and festoons, as shown in figures 114 and 115, said to 

 have been observed by Fraenkel, often are present, especially on the villi, although 

 in a few instances fine buds and frameworks of syncytium also were seen arising 

 from the epithelium of the chorionic membrane. This feature (shown in fig. 115) 

 has, I believe, not been specially emphasized heretofore, though observed by 

 Clivio (1908). 



Mounds formed by the Langhans layer were common, especially on the tips 

 of the villi where they frequently formed irregular masses of small nodules the 

 "appendici durate" of Crosti (1895). These gave the villous tree the appearance 

 of a leafless orange loaded with fruit, only that the trophoblastic nodules are mainly 

 apical, as shown in figure 116. In several instances syncytial buds were found far 

 out on these trophoblastic masses, a fact which is of special if not of crucial sig- 

 nificance in connection with the old question of the origin of the syncytium, for 

 these buds undoubtedly had not been transported there. But, however one may 

 regard these things, such appearances as represented in figure 9 (plate 1, Chapter 

 IV) are unmistakable, for they show thickenings composed of Langhans cells and 

 garlands of considerable length, portions of which are composed of absolutely 

 distinct cells of the Langhans type, as well as other portions composed of syncy- 

 tium with every gradation between the two. Nor do I believe that the assumption 

 that syncytium can resolve itself into individual cells can be used to deny the 

 implication of these facts. 



