352 HYDATIFORM DEGENERATION IN TUBAL AND UTERINE PREGNANCY. 



condition of the epithelium in the these cases, and that such differences actually 

 exist is beyond question. 



Marchand's revolutionary investigation on chorio-epithelioma notwithstanding, 

 the epithelium is not always two-layered, nor is it always thickened, in hydatiform 

 mole. That the epithelium can not always be active beyond the normal follows also 

 from the fact that the proliferative changes in it are subsequent to, even if not 

 necessarily consequent upon, changes in the stroma. Furthermore, like the latter 

 they are gradual in their evolution and may stop or be stopped at any stage of their 

 development. Then, too, the condition of the epithelium depends very largely upon 

 the preservation of the abortus, and this, as is well known, varies greatly. 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, usually is the case. The stroma, on the other hand, probably not 

 being wholly independent of the contained capillaries, 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. 



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

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

 syncytium and trophoblast very often show evidences of a marked activity which is 

 not confined to implanted villi or to the epithelium of the villi as a whole, but which 

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

 syncytial buds, whorls and festoons, as shown in figures 22, 23, and 24, and as said 

 to have been observed by Frankel, 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 figure 23) 

 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 25. In several instances syncytial buds were found 

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

 significance 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 24 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 syncytium with every gradation between 



