298 ARTHUR WILLIAM MEYER. 



versity by Dr. Eugene V. Falk, of Modesto, California, had the 

 villi rather sparsely and irregularly distributed as Fig. 7 shows. 

 However, the entire specimen was so splendidly preserved that 

 investigators of unique opportunity and experience were 

 uncertain as to its normality. Even after careful inspection 

 under low magnification the writer, too, felt uncertain, but on 

 receipt of the specimen he had informed Dr. Falk that it prob- 

 ably was pathologic. This opinion was based almost wholly on 

 the irregular distribution of villi, their complete absence on part 

 of the surface; on the large size of the yolk sac; the unusual 

 translucence of the entire specimen; and upon the apparent 

 absence of the embryonic disc. About one-third of the entire 

 surface of the chorionic vesicle was devoid of villi and where 

 they were present they seemed to be in widely different stages of 

 development. They differ markedly not only in length and in 

 diameter but also in the complexity of their branching. Some 

 which w r ere represented by fine threads merely were found to be 

 represented by stroma only, the epithelium having been stripped, 

 probably during the removal of the blood in which the specimen 

 was imbedded before it was received at the laboratory. Other 

 villi are torn, those which are preserved are clubbed but slightly 

 and some are so short that they look like little droplets on the 

 surface of the chorionic membrane. Those near the bare areas 

 are almost transparent but nearer the other pole they become 

 more opaque. The caliber varies from 1/6 to I mm. and the 

 greatest length is 2.25 mm. The chorionic vesicle measured 

 6x4x5 mm. and the partially invaginated yolk sac, 2 x 2.6 x 1.8 

 mm. A smaller, less transparent vesicle, which was thought to 

 represent the amnion, was seen between the yolk sac and the 

 chorionic membrane, but no embryonic disc could be recognized. 

 An examination of the microscopic sections of this vesicle showed 

 that it was macerated. The epithelium is missing in many 

 places and the histologic details are wanting. Hence this 

 chorionic vesicle very evidently ceased to live some time before 

 it was aborted, and this conclusion is corroberated also by the 

 clinical history. The menstrual age of the specimen is 39 days 

 but the chorionic vesicle, which was approximately spherical, 

 measured only 6.5 mm. instead of 25 mm. to 30 mm. as implied 



