TEE GENITAL ORGANS OF THE MALE. 



979 



developed, and presents, internally, a longitudinal fibrous cord; it is not much dilated during 

 erection. In this act, the penis is elongated by the straightening out of its curvatures, rather 

 than by any real lengthenings; when erection ceases, the organ is retracted into the preputial 

 cavity by the contraction of the suspensory ligaments, which reform its double inflection behind 

 the scrotum. 



In the Ram, the disposition of the testicles and vasa deferentia is somewhat similar. The 

 membranous portion of the urethra has no prostate, but quite posteriorly it has two small 

 Cowper's glands, the upper face of which is covered by a red muscular layer that leaves the 

 origin of the bulbous portion and is lost on this surface. Tl)e muscles are disposed as in the 

 Bull. But the spongy portion of the urethra is not enveloped by the corpus cavernosum, 

 which is channeled, as in Solipeds, by a furrow that lodges the urethra. The head of the 

 penis is remarkable for two lateral folds, disposed like wings at the base of the glans. One 

 of these is only slightly developed, so that the head of the penis looks asymmetrical. The 



Fig. 527. 



PENIS AND MUSCLES OF THE PREPUCE OF THE BULL. 



1, Protractor muscle of the prepuce; 2, retractor of ditto; 3, testicles in the scrotum ; 4, the S o( 

 the penis; 5, suspensory ligaments of the penis attached to the second curve; 6, subcutaneous 

 abdominal vein. 



urethra is also prolonged by a vermiform appendix from 1 to Ij inches long. (In the Ram, the 

 extremity of the urethra has tlie form of a narrow cylinder curved backwards, its opening being 

 a longitudinal slit. In Ruminants, towards the extremity of the prepuce are small teats; 

 these, in the He-goat, are sometimes glandular, and secrete a fluid analogous to milk.) 



Pig. — The testicles of this animal are round, and placed in the perinseal region. The 

 scrotum is narrow, and but little detached : the pouches of which it is composed appearing 

 simply as two hemispherical prominences on the surface of the perinseum. There is nothing 

 particular to be remarked in the epididymis and vas deferens; (the tail of the first is very- 

 voluminous; the latter has no pelvic dilatation.) 



Tlie vesiculsB seminales, with regard to disposition, are intermediate between those of the 

 Horse and Ox. Their walls are thick and very glandular, and their interior is diverticulated. 

 (They are, proportionately, very large, and, in structure, closely resemble those of Ruminants; 



