THE INTERNAL ORGANS OF REPRODUCTION 425 



The cytoplasm surrounding the germinal vesicle 

 is granular in appearance, and is called the vitellus; 

 the outer margin of the cytoplasm is surrounded by 

 a delicately striated border called the zona pellucida. 



The ovum is the cell which is fertilized by the 

 spermatozoon of the male and develops into the embryo 

 and its ultimate creation, the human being the 

 infant. 



FIG. 149 



Theca _ ^^'' 



folliculi . ^V^*"^ 



(fibrous coat] /,' ' 7,' 



embrana _ 



Antrum f^ 



fuHicnlt I ' 

 th liquor'",'"'.' 

 folliculi 



Di.KCK 



roligerus- v ' 

 sews- pru 

 ligerous) \ 

 mm with 



a, genm- ., .;; % .;.>"'. 



',1 vesicle, ScV'^vJ-V:*; /- V.^J. ' ' '-^ / 



id germi- ^'>^V^V"'t'i.^'"-''"^*' f V''V 



I!/, >(,(!- ^ V. \^^y*V?''l : >vX :; /''; /' f -/.'v 



vessel N^^V4\"; V-'4& ''ICV''^^'^"/^''''''^-'-^^.*'^^ 



- <.*!>*v . > ,, ,'*!','* 



' ; ^vi.'.^'' 



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

 (Szymonowicz.) 



Ovulation. This is the term used to describe the 

 process whereby the mature Graafian follicle ruptures 

 and the ovum is forced through the layers of the ovary. 

 When the female reaches the age of puberty (which varies 

 in different races and in certain climates) the Graafian 



