454 CATHARINE LINES CHAPIN 



20 cm. free-martin may justly be compared with a 20 cm. normal 

 embryo of either sex, as well as with its twin, the normal male. 



In the description of the reproductive glands and related or- 

 gans which follows, most of the terms are employed in their 

 usual sense; Wolffian body, epididymis, epoophoron. Wolffian or 

 mesonephrotic duct and Miillerian duct, germinal epithelium and 

 others. A few terms, which have not been used in their ordinary 

 sense may best be explained at this point. Rete is used to de- 

 scribe the network of tubules of the rete testis, the rete ovarii 

 which for the most part degenerates, and the modified rete of the 

 free-martin which persists. The term sex cords is used to des- 

 ignate the proliferation of the germinal epithelium in the two 

 sexes. In the male, there is one set of sex cords, the seminif- 

 erous tubules. In the female there are two sets of sex cords; 

 first, the medullary cords which degenerate during foetal life 

 and second, the cords of Pfliiger, at the inner ends of which are 

 formed nests of cells including the primordial ova, the primary 

 ovarian follicles. 



The term albuginea is used to designate the tissues lying 

 just beneath the peritoneum and surrounding the sex cords, in- 

 cluding not only the tunica albuginea, but also the tunica vascu- 

 losa which, in the male embryo, merges into the tunica albuginea. 

 According to Allen^ this term is equally applicable to the similar 

 structure found in the adult female, between the cords of Pfliiger 

 and the germinal epithelium, but which has not yet developed to 

 any great extent in a 29.5 cm. female (N20). For the sake of 

 clearness this structure is designated definitive albuginea, to 

 distinguish it from the primary albuginea which separates the 

 medullary cords from the cords of Pfliiger. 



The term interstitial cells is used to refer to those cells de- 

 scribed by R. H. Whitehead^ as the cells of the interstitial 

 gland; interstitial material refers to all the material between 

 the seminiferous tubules, including not only the interstitial cells, 

 but also the connective tissue stroma. 



1 B. M. Allen, Am. Jour. Anat., vol. 3. 



'^ R. H. Whitehead, Am. Jour. Anat., vol. 3. 



