GENERATIVE ORGANS. 



PS KE 



325 



FIG. 254. SECTION THROUGH A PORTION OF THE OVARY OF A MAMMAL, SHOWING 

 THE MODE OF DEVELOPMENT OF THE GRAAFIAN FOLLICLES. 



KE, germinal epithelium, ingrowths from which extend into the stroma of the ovary 

 to form the ovarian tubes (PS) : the stroma is penetrated by vessels (g, g) ; 

 Z7, U, primitive ova ; S, cavity between the follicular epithelium (tunica granu- 

 losa, Mg) and the primitive ova ; Lf, liquor folliculi ; D, discus proligerus ; Ei, 

 ripe ovum, with its germinal vesicle (K) and germinal spot ; Mp, zona pellucida, 

 showing radiated structure ; Tf, theca folliculi. 



FIG. 255. DIAGRAMMATIC SECTION OF THE TESTIS OF A MAMMAL. 

 Ho, testis ; NH, epididymis ; Vd, vas deferens ; A, albuginea of the testis, which 

 gives rise to the trabeculse (t, t) and the corpus Highmori (t) ; L, L, coils of the 

 seminal tubules ; Ve, vasa efferentia (rete Halleri) ; Cv, coni vasculosi, which 

 are connected together by the collecting duct, Vep ; Fa, vas aberrans. 



As regards the male generative organs of Mammals, the 

 testes arise in the same position as do the ovaries of the female. 



