384 Maximilian Herzog. 



development secretes an enzyme whiph diffuses into the surround- 

 ing maternal tissues and here causes coagulation necrosis and com- 

 plete degeneration of cells. The trophoblast cells, as represented by 

 our specimen, are certainly not phagocytic in the ordinary sense of 

 the word. We have in vain examined and re-examined our sections 

 to find included in the trophoblast cells or the syncytium maternal 

 blood corpuscles, fixed tissue cells or fragments or remnants of the 

 same. We must, therefore, conclude that the effect of the tropho- 

 blast upon the maternal tissue is brought about not by true phago- 

 cytosis, but through the action of an enzyme. If the latter destroys 

 maternal cells to a large extent, and this destruction, of course, 

 takes place, as can be seen, we have those conditions which under 

 any circumstances would lead to violent inflammatory reac- 

 tion, including enormous dilatation of veins and capillaries ; free 

 hemorrhages ; and if the process take place in a glandular mucosa, 

 with hypertrophy of the glandular apparatus. And, indeed, if we 

 look upon the decidua in our specimen particularly, as seen in 

 Fig. 24, to the left of the ovum, and in Fig. 26, in the whole 

 section, the resemblance between them and a typical, well-marked 

 case of endometritis glandularis hypertrophica is very striking. In 

 fact, when the set of sections represented by Fig. 2(i was shown to 

 a very competent pathologist with the statement that it was very 

 probably a very early decidua and that an ovum would be found in 

 the block of tissue, he ridiculed the idea and firmly held that the 

 section simply showed a typical strougly-marked case of endometritis 

 glandularis hypertrophica. 



If we behold the great destructive tendencies of the early tro- 

 phoblast, the question presents itself. Why does this process evidently 

 come almost to a standstill somewhat later in the course of gesta- 

 tion ? Two possibilities present themselves. Either the secretion of 

 the supposed destructive trophoblast-enzyme is limited as to time, 

 or there is established a temporarj'^ immunity of the maternal tissues. 

 These speculations, while at present entirely hypothetical, might 

 perhaps be supported by experiments in which the effect of filtered 

 extracts of animal placentae of various stages of development, and in 

 repeated applications^ upon the uterine mucosa, would have to be 

 studied. 



