OVARIES. 241 



plasm stores up in itself nourishing material in the form of a 

 granular substance, so that the greater part is converted into 

 the so-called deutoplasm. Thin layers around the nucleus and 

 at the periphery of the ovum remain unchanged. The deuto- 

 plasm and protoplasm together form the yolk. 



The excentrically lying nucleus of the ovum is spherical, 

 clear, and vesicular, and possesses a distinct nuclear membrane 

 with a double contour. On account of this structure, the 

 nucleus is known also as the germinal vesicle (vesicula germ- 



FIG. 185. 



Theca 

 folliculi' 





Mcmbrana 



granulofta 



Antrnni 



folJicnli I 



with l't(jtH-~~. 



folliculi 



Cumulus \> 



oophorns ^ 



(i rii ni n'llJi i 

 zona peflu- 

 cida, (jet-mi- ' *T 

 IK-! reside, 

 tnifl (termi- 

 nal spot 



Blood-. 



vessel 



Section through a Graafian follicle from an ape's ovary. X 90. 



inativa). In the chromatin network is present a distinct 

 nucleolus, which is called also the germinal spot (macula germ- 

 inativa), and in which amoeboid movements have been observed 

 (Nagel). 



At the same time, changes take place in the follicle, begin- 

 ning in a collection of serous fluid between the follicular cells 

 (liquor folliculi}. This is contained in a cavity, which gradually 

 becomes larger, and is known as the antruni folliculi The 

 fluid is due partly to a translation from the vessels surround- 



