522 



THE EEPEODUCTIVE SYSTEM 



accompanies the extrusion of the unfertilized ovum. The true corpora 

 lutea are of relatively large size and persist for many months, the 

 spurious are somewhat smaller and persist for little more than one 

 month; yet both pass through the same histological process of develop- 

 ment and degeneration and both leave their scars in the substances of 

 the ovarian stroma. 



Ovarian scars also arise through atresia of the larger follicles, the 

 degeneration of whose epithelium is followed by an ingrowth of tissue 

 derived from the theca folliculi, and the gradual development, organiza- 



FIG. 459. A CORPUS ALBICANS, FROM A SECTION OF THE HUMAN OVARY. 

 X 75. (After Williams.) 



tion, and final contraction of the connective tissue, forming, as it were, 

 a minute but imperfect corpus albicans, in the center of which is often 

 the shrunken degenerating remains of the ovum. Certain small acido- 

 philic homogeneous bodies, the so-called Call-Exner bodies, of uncertain 

 significance are also occasionally present in the stratum granulosa of the 

 ovarian follicles. 



Blood Supply. The blood-vessels of the ovary are derived from the 

 branches of the ovarian and iiterine arteries. These vessels enter the 

 ovary through the mesovarium and divide into numerous branches which 

 pursue a peculiar spiral or corkscrew course through the stroma of the 

 medulla, and finally enter the cortex. They possess thick muscular 

 walls containing bundles of longitudinal smooth muscle fibers. In the 

 cortex they supply capillaries to the stroma, and in the theca folliculi of 

 the Graafian follicles they form rich plexuses of broad capillaries and 



