516 



THE REPRODUCTIVE SYSTEM 



a layer of folliculnr epithelium several cells deep. This may be desig- 

 nated the maiiHc-lai/fr. 



The rapid multiplication of the epithelial cells is soon followed by 

 active secretion, resulting in the formation of a clear fluid by which 

 the cells are more and more separated, and the cytoplasm of adjacent 



a 



FIG. 455. A NEARLY RIPE GRAAFIAN FOLLICLE FROM THE OVARY OF A DOG. 



a, fibrous, and 6, cellular layer of the theca folliculi; c, membrana propria; d, mem- 

 brana granulosa, which, as a result of contraction during hardening, has retracted 

 from the membrana propria, leaving a broad artificial space; E, liquor folliculi; 

 /, discus proligcrus; g, zona pellucida; h, vitelline membrane; i, vitellus; k, the ger- 

 minal spot, lying within the germinal vesicle. Hematein and eosin. Photo. X 150. 



cells is then readily seen to be firmly joined together by numerous deli- 

 cate processes which may be regarded as iiiferccllulrir bridges. Similar 

 processes unite the neighboring cells to the /on a. pellucida which lias 

 already formed about the ovum. 



The accumulation of the fluid lit/nor folliculi within the follicle soon 

 appears to tear apart certain of the epithelial cells, and a fluid-filled space, 



