THE REPRODUCTIVE SYSTEM 361 



by a layer of epithelial cells becomes separated from its neighbors 

 (Fig. 253, fp). This central ovum surrounded by a single layer of 

 epithelial cells (folU cul ar cells ) is the primitive Graajj-m fol licle (Fig . 

 253,//), Fig. 254, and Fig. 255, a). Rarely a follicle may contain more 

 than one ovum, of which, however, only one goes on to maturity, 

 the others degenerating. The foUicle increases in size, mainly on 

 account of prohferation of the follicular cells, which^oon iorm several 

 layers instead of a single layer, but also partly on account of 'growth of 



IP 



:*!.; 



-^^i.wtcsi-i* *"<lBi 





• « » » s * •^ - 



'S. 



-."^n 



c 



Fig. 253. — FromTransverseSectionof Ovary of New-born Child. X280 (Sobotta). 

 Shows primitive ova in germinal epithelium; P'fliiger's egg cords and nests_ of cells; c, 

 capillaries; he, germinal epithelium; str, stroma.; fp, primitive follicles; op, primitive ova. 



the o\Tim itself (Fig. 255). The latter now leaves the centre of the 

 foUicle and takes up an eccentric position. - At the same time a cavity 

 (or several small cavities which later unite) appears near the centre 

 of the follicle (Fig. 255, e and Fig. 252, 7). This is filled with fluid 

 which seems to be in part a secretion of the folhcular cells, in part a 

 result of their disintegration. The cavity is known SiS the follicular 

 cavity or^ aMrum, the fluid as the liquor folliculi. Lining the follicular 

 cavity are several rows of follicular cells with granular protoplasm — 

 the stratum granidosum. With increase in the liquor folliculi the 

 ovum becomes still further pressed to one side of the follicle, where, 

 surrounded by an accumulation of follicular cells, it forms a distinct 

 projection into the cavity (Fig. 257, and Fig. 252, 8 and 9). This 



