DEVELOPMENT OF THE GKAAFIAN FOLLICLE 401 



lular bridges. Similar processes unite the neighboring cells to the 

 zona pellucida which has already formed about the ovum. 



The accumulation of the fluid liquor folliculi within the fol- 

 licle soon appears to tear apart certain of the epithelial cells, and 

 a fluid-filled space, the antrum folliculi, is thus formed. This 

 space is characteristic of the true Graafian follicle. The epithelial 

 cells are separated by the antrum into two layers : the one, adher- 

 ent to the membrana propria of the follicle, is known as the 



FIG. 324. A GRAAFIAN FOLLICLE OF THE HUMAN OVARY. 



From within outward are seen the germinal spot, germinal vesicle, vitellus, vitelline 

 membrane, zona pellucida, granule cell layer, membrana propria, and theca folliculi. The 

 ovarian stroma forms the border of the figure. Hematein and eosin. Photo, x 575. 



membrana or stratum granulosum ; the other, adherent to the 

 zona pellucida of the ovum, is designated the discus proligerus. 

 The two layers remain in contact at one point, and as the liquor 

 folliculi increases in volume, the attached discus proligerus with 

 its contained ovum comes to occupy a more and more eccentric 

 position, and the cells of the stratum granulosum, where the two 

 layers are in contact, appear to pile up about the ovum in the 

 form of a hillock, the so-called cumulus oophorus. 

 27 



