CS. LVIII.] 



THE OVARY 



821 



pass to the neck of the spermatozoon, and the cytoplasm of the 

 spermatid is transformed into the parts of the body and tail of the 

 spermatozoon. 



FEMALE ORGANS 



The Ovary is a solid organ composed of fibrous tissue (stroma), 

 containing near its attachment to the broad ligament a number of 

 plain muscular fibres. It is covered by & layer of cubical cells, the 

 so-called germinal epithelium, which, in young animals, is seen 

 dipping down, here and there, into the stroma. The stroma contains 

 a number of yellow polyhedral cells similar to the interstitial cells 

 of the testicle. 



Sections of the ovary show that the stroma is crowded with a 



FIG. 613. Diagrammatic view of the uterusTand its appendages, as seen from behind. The uterus and 

 upper part of the vagina have been laid open by removing the posterior wall ; the Fallopian tube, 

 round ligament, and ovarian ligament have been cut short, and the broad ligament removed on the 

 left side ; u, the upper part of the uterus ; c, the cervix opposite the os internum ; the triangular 

 shape of the uterine cavity is shown, and the dilatation of the cervical cavity with the rugae termed 

 arbor vita? ; v, upper part of the vagina ; od, Fallopian tube or oviduct ; the narrow communication 

 of its cavity with that of the cornu of the uterus on each side is seen ; I, round ligament ; lo, liga- 

 ment of the ovary ; o, ovary ; t, wide outer part of the right Fallopian tube ; fi, its fimbriated 

 extremity ; po, parovarium ; h, one of the hydatids frequently found connected with the broad liga- 

 ment, i. (Allen Thomson.) 



number of rounded cells, the oocytes, derived from primitive germ 

 cells, which, in the early stages, were intermingled with the cells of 

 the germinal epithelium. There are also numerous vesicles of differ- 

 ent sizes which are called Graafian follicles. The smallest follicles 

 are near the surface, the largest are deeply placed, but as they ex- 

 pand they again approach the surface, and ultimately rupture upon it. 

 A Graafian follicle has an external wall formed by the stroma ; 

 this is lined internally by a layer of cells derived from the germinal 

 epithelium which surrounds the oocyte. At a later stage there are 

 two layers of cells, one lining the cavity, and the other surrounding 

 the oocyte, but the two are close together. A viscid tiuid collects 

 between the two, and as the follicle grows, separates them. 



