288 HISTOLOGY. 



* 



nacula testis, and sometimes the peritoneal cavity is prolonged into 

 them forming a processus vaginalis. In late stages of development 

 they become large enough to conceal the clitoris and labia minora 

 which previously projected between them. 



OVARY. 



The ovary is an oval body about an inch and a half long, covered 

 by a modified portion of the peritonaeum. Along its httus it is attached 

 to a mesentery, the mesovarium, which is a subdivision of the broad liga- 

 ment of the uterus. The epithelium of the mesentery is continuous with 

 that of the ovary, and the mesenteric connective tissue joins the mass 

 which forms the central part of the ovary. This tissue, rich in elastic 



FIG. 329. CROSS SECTION OF THE OVARY OP A CHILD EIGHT YEARS OLD. X 10. 



i, Germinal epithelium; 2, tunica albuginea; 3, peripheral zone with primary follicles; 4, vesicular fol- 

 licle; 5, stroma ovarii; 6, mediastinum; 7, 8, peripheral sections of vesicular follicles; 9, hilus, con- 

 taining large veins. 



fibers and tortuous blood vessels accompanied by strands of smooth 

 muscle fibers, is sometimes called the medulla of the ovary but may per- 

 haps be better named the mediastinum. The peripheral part, except at 

 the hilus, consists of the connective tissue stroma ovarii together with the 

 primary and large vesicular follicles which it surrounds. Just beneath 

 the ovarial epithelium it forms a dense layer consisting of two or more 

 strata, the tunica albuginea. 



The formation of follicles. The germinal or peritonaeal epithelium 

 of the ovary consists of a single layer of small cells which may become low 

 columnar or flat. Even after birth sexual or "egg cells" may be found 

 in it (Fig. 330). The egg cells divide by ordinary mitosis in the epithe- 

 lium and in the detached islands of peritonaeal cells in the stroma. At 

 sexual maturity nearly all of these islands have been separated into pri- 



