220 DR. JAMES FOUMS. 



brana granulosa are thus derived from the corpuscles of the 

 connective tissue stroma, and not, as Waldeyer states, from 

 the germ epithelial corpuscles. The follicular space is formed 

 by a breaking down and probable solution of certain of the 

 corpuscles of the thickened follicular epithelium in the midde 

 parts of the same. The discus proligerus consists of folli- 

 cular epithelial corpuscles, which are in contact with the 

 zona pellucida of the ovum. The zona pellucida or vitelline 

 membrane is formed by a hardening of the outer part of the 

 yelk or protoplasm of the ovum, and is not, as Reichert, 

 Pflilger, and Waldeyer stated, a product of the follicular 

 epithelium. At birth the human ovary contains not less than 

 35,000 ova, few of which reach maturity. 



In the human ovary at birth the germinal vesicles measure 

 ttV-o^^ to tt'o-o^^ of an inch. Most of them are about the 

 same size, and present a sharply-defined membranous wall. 

 In some germinal vesicles two or three germinal spots are 

 seen. The tunica albuginea is the thickened stroma growing 

 round the ovary. At the age of two and a half years all 

 formation of ova from the germ epithelium has ceased. 



Graafian follicles are not formed from tubular structures 

 in the manner described by Pfliiger, Spiegelberg, and 

 Waldeyer. The appearance of tubular structures passing 

 into the stroma of the ovary are produced by sections through 

 furrows and depressions between irregular prominences on 

 the surface of the foetal ovary. The irregularities of the 

 surface of the fcetal ovary are produced at first by the 

 expansion of egg clusters upwards under the germ epithe- 

 lium. When the walls of furrows and depressions come in 

 contact, egg clusters are formed by the imbedding of germ 

 epithelial corpuscles in that situation, just as in other situa- 

 tions. Egg clusters are formed in connection with the germ 

 epithelium lining the furrows and depressions. Among the 

 germ epithelial corpuscles lining the furrows, &c., we find 

 large primordial ova, and corpuscles in all stages of develop- 

 ment into the same, just as in other situations among the 

 ordinary germ epithelial corpuscles. 



In the human foetus, round and oval-shaped groups of 

 germ epithelial corpuscles are found in connection with the 

 germ epithelium all round the ovary. When vertical sections 

 are made through these they present the appearance as if 

 tubular structures filled with developing germ epithelial 

 corpuscles passed from the germ epithelium downwards into 

 the stroma of the ovary. 



The development of the corpuscles of the membrana 

 granulosa, from connective tissue corpuscles of the stroma. 



