CHAPTER XIV. 



THE ISIALE REPRODUCTIVE SYSTEM. 



In the male vertebrate the organs of reproduction generally 

 consist of a pair of testes, in which spermatozoa are produced; 

 ducts by which the sperm are carried away from the testes; and 

 glands, whose secretions are added to the sperm passing through 

 the ducts. 



DEVELOPMENT OF THE TESTES. 



As in the case of the developing ovary already described, there 

 is an indift'erent stage of gonad development during which both 

 testis and ovary cannot easily be distinguished. Relatively early. 



OVARY <: 



^TESTIS 



Germinal 

 epUhelium 



Egg cord 



Primary 

 follicle 



Medullary cord 



Interstitial cell 



Rcfe ovarii 

 Epoophoroii 



Germ inal epithelium 



^i minifcrous tubule 

 Inter.stili(d cell 



ft(./f/r.s//.s 



-Efferent duct 



Wolffian duct 



Fig. 145. — Diagram of the development of the testis and ovary. 

 (Adapted from Kohn.) 



however, there is the bcgimiing of dllVereiitiai de\el()])iiu'iit leading 

 to formation of either male or female organs of re])r()(hiction. 

 (Fig. 145.) 



The (level()i)ing cords of cells, wliicli in the ovary broke into 



