THE ACCESSORY REPRODUCTIVE ORGANS 257 





Fig. 69. — Pai't of tiansveise section through penis of nionkey. 



<(, Erectile tissue ; '>, urethra ; .•, ai'teiy ; d, nerve ; e, Pacinian Lody ; 

 /, fold of epithelium ; </, surface epithelium. 



particularly large in the walrus. In the Cetacca the penis is often 

 of enormous size (six feet in length in some species), and terminates 

 in a point, but is otherwise normal. It can be withdrawn into the 



9 



