URINOGEN1TAL ORGANS. 



301 



In the first case the other product of the segmental duct, or 

 so-called secondary mesonephric duct, serves primarily in the 

 male as the urinogenital duct (Ley dig's duct), and in the 

 female simply as the urinary duct (Figs. 237, 238A and B, 

 w.d, vd, and 240, A, B, lg t Ig (Ur). 



In the second case, the entire primary mesonephric duct gives 

 rise in the male to the seminal duct (Fig. 236, C, Vd) 



A 



B 



FIG. 236. DIAGRAM EXHIBITING THE RELATIONS OF THE FEMALE (A) AND OF THE 

 MALE (C) REPRODUCTIVE ORGANS TO THE GENERAL PLAN (B) OF THESE 

 ORGANS IN THE HIGHER VERTEBRATA. 



MG, Milllerian duct ; Ut, uterus ; Ot, abdominal aperture of the Fallopian tube ; 

 Vg, vagina Vm, uterus masculinus ; GM, hydatid of Morgagni ; WG, Wolfi&an 

 duct; Gg, Gartner's? duct ; Vd, vas y deferens ; DC, ductus ejaculatorius ; Vs, 

 vesicula seminalis ; Urn, mesonephros ("Wolffian body) ; Po, parovarium ; Ep, 

 epididyrnis ; g, genital gland ; Ov', ovary ; Ho, testis ; N, kidney" ; Ur, ureter ; 

 B, urinary bladder ; Su, urinogenital 'sinus ; Cl, cloaca ; Ba, gland of Bartho- 

 lini ; GD, Cowper's gland ; Pr, Pr, prostate gland ; , rectum ; Ggl, copulatory 

 organ. (In Fig. A the clitoris is indicated, but not lettered.) 



(Wolffian duct 



or 



vas deferens), while in the female it 



usually becomes rudimentary, and is then spoken of as Gartner' s 

 duct (Fig. 236, A, Gg). The metanephric duct or ureter 

 (Fig. 236, Ur) (which is possibly confined to the Amniota), 2 serves 

 to carry off the products of urinaiy excretion in both sexes. 



1 The term Wolffian duct is used to describe the duct of the mesonephros after 

 the formation of the Mlillerian duct, whether the latter is developed independently 

 or not. 2 Comp. note on p. 298. 



