400 



HISTORY OF THE HUMAN BODY 



into its own lumen, thus forming a direct outlet from the 

 ductus deferentes to the exterior. At the same time the free 

 end becomes protruded from the cloacal orifice, and the organs, 



a 



FIG. 112. Relationships of the male urogenital organs in mammals. 

 [After WEBER.] 



(a) Monotremes. (b) Marsupials. (c) Placental mammals. 



s, symphysis pubis; in, intestine; v, urinary bladder; u, ureter; t, testis; w, ductus 

 deferens; p, prostate; g, vesicular gland; c, bulbo-urethral gland; cp, corpus 

 cavernosum penis; cu, corpus cavernosum urethrze (^corpus spongiosum). 



