80 STUDIES ON PATHOLOGIC OVA. 



preserved long after cell outlines can no longer be recognized. Later they become 

 very irregular and finally disappear completely, leaving only a glassy substance 

 which fills the otherwise well-preserved epithelial shell. The latter usually stands 

 out in marked contrast to the degenerated stroma. The epithelium not only is 

 well preserved, but the syncytium is often absent and the trophoblast shows 

 signs of marked activity. Usually it is increased in amount and "appendici 

 durate" are relatively common. 



During the process of this degeneration even the very young villi become 

 swollen, so that their unusual caliber, and also the great variation in size of dif- 

 ferent portions of the same villus and of different villi at once attract attention. 

 The walls are often smooth, buds are absent, and the villi are sparse though long. 



Since none of the specimens of this group had been designated specifically as 

 hydatiform moles, and especially since an inspection of the gross specimens did 

 not confirm the existence of what currently passes for hydatiform or cystic de- 

 generation of the chorion, the contrast between the microscopic and gross pictures 

 was at first puzzling. However, under low magnification with the binoculars 

 (about 4 to 20 times), every one of the specimens which was found to show the 

 characteristic changes in the villi under higher magnification was also found to 

 contain villi or groups of villi, the form of which was typical of hydatiform moles. 

 In some instances it was necessary to remove a small group of villi and carefully 

 separate them by teasing before the typical gross changes could be observed. In 

 other instances in which a severe infection apparently had supervened upon the 

 hydatiform degeneration, or in which the villi were glued for other reasons, no 

 good preparations could be made by this means. However, it was found that an 

 examination of the cut surfaces of the chorionic vesicles, especially when embedded 

 in celloidin, under similar magnification would always easily reveal the presence 

 of this degeneration. In one specimen, for example, which was obtained by hys- 

 terectomy, the chorionic vesicle was still embedded within the uterus and the 

 implantation cavity extended around the greater portion of its periphery. The 

 microscopic examination of a section from this uterus showed the presence of the 

 characteristic degenerations, and upon examination numerous groups of typical 

 vesicles could be seen lying in the cut surface of the densely matted villi. In 

 view of these facts, I can no longer entertain any serious doubt as to the nature 

 of these changes. It stands to reason, however, that the very incipient histologic 

 changes undoubtedly could not be verified by gross examination, for neither the 

 structure, the optical properties, nor the form of the villi in such specimens would 

 have changed sufficiently from the normal to become evident under low magni- 

 fication. 



B. T0BAL. 



Since two of the four specimens originally placed in this group belong in groups 

 1 and 2 respectively, only two remain here. The tube of one was not included in 

 the sections, but the walls of the other tube were infiltrated and the villi exemplified 

 a fine case of hydatiform degeneration in its early stages. Some of them which 

 were still implanted evidently were being detached by the hemorrhage, and both 



