PHYSIOLOGICAL PROPERTIES OF GONADS 



149 



general behavior of the foHicles seems to follow this line of devel- 

 opment; this one exception is a case to be described in the next 

 section, where there are cells that resemble to a very great degree 



Fig. 12 Section of normal ovary from rat thirty-six days after birth, showing 

 normal and atretic follicles. Follicles A, B, C, and D show beginning atresia 

 (the discus proligerus is degenerating). Ovum in follicle D shows parthenogen- 

 etic cleavage, three of the four cells visible. 



the ordinary lutein cell of the corpus luteum. Aside from this 

 one case, there has been absolutely no indication that ovulation 

 has occurred in any of these grafts. 



