AND ABDOMINAL VISCERA. 29 



formed by the corpus spongiosum, in the middle of 

 which lies the urethra. The sides and upper surface 

 are formed by the two corpora cavernosa, white tough 

 bodies which are very vascular, and are attached to 

 the ischial bones. At the distal end of the penis these 

 bodies end in the long \\\\c}^ glans penis, which forms 

 the terminal portion of the corpus spongiosum. A 

 cross-section through the penis will give a good view 

 of the arrangement of the three corpora of which it is 

 composed. 



11. The Os Penis. In the glans penis and for a 

 short distance between the corpora cavernosa is found 

 the large penis bone. It lies over the urethra, and is 

 grooved on the under side. 



12. The Prepuce. The end of the glans penis is 

 covered by a movable fold of the integument, the 

 prepuce. 



