266 



STRUCTURE OF THE VERTEBRATES 



cloaca in the marsupials, the penis becomes enclosed within its 

 own sheath, and projects posteriorly from its attachments on 

 the pubic and ischial bones. The organ of the placentals is 

 structurally the same, although it projects anteriorly from its 



Ureter 



Inguinal opening 



Prepuce 

 Glan^ 



Epididymi 



Fig. 148. Sagittal Section of Human Male. 



origin on the pelvis. In the majority of the placentals the 

 organ is enclosed within a preputial sheath and is protruded 

 when the erectile bodies are engorged with blood. The penis is 

 pendant (not enclosed within a sheath) in the bats and primates. 



