4 Diseases of the Genital Organs 



and readily separates the two groups between the dartos 

 and cremaster so that he may ligate the structures of intra- 

 abdominal origin just at, or near to, the internal inguinal 

 ring. 



In domestic animals, except the elephant, the descent of 

 the testicles into the scrotum is a prerequisite to fertility; 

 otherwise, spermatozoa are not formed. 



In the descent of the testicle, the gubernaculum shortens, 

 the pi'ocessus vaginalis develops, and the tail of the epididy- 

 mis with the caudal end of the testicle traverses the inguinal 

 ring followed by the body and head of the epididymis and 

 cephalic end of the testicle. 



The descent of the epididymis and testicle of ruminants 

 is directly downward. The gland comes to rest with the tail 

 of the epididymis and that portion of the testicle which was, 

 in the embryo, the posterior end directed downward. The 

 long axis of the testicle is perpendicular to the spinal column. 

 The epididymis thus rests upon the postero-lateral face of 

 the testicle, its head directed toward the internal inguinal 

 ring, its tail at the distal end of the testicle. The vas de- 

 ferens passes inward across the lower margin of the mesor- 

 chium and turns upward on the postero-median surface of 

 the testicle closely applied to it. The epididymis and vas 

 deferens are thus parallel and separated from each other by 

 the mesorchium or peritoneal fold connecting the visceral 

 and parietal layers. It is important to remember this ar- 

 rangement of structures when examining clinically the testi* 

 cles for evidences of disease. 



In solipeds the cutaneous attachment of the gubernaculum 

 testis is farther posterior and higher than in ruminants. 

 This draws the tail of the epididymis upward and backward 

 causing its head and the corresponding end of the testicle to 

 tilt forward. The gland revolves through 90 degrees on its 

 short axis and comes to rest with its long axis parallel to the 

 spinal column. The vas deferens, instead of doubling back 

 along the postero-median surface of the testis as in the rumi- 

 nant, leaves the horizontal testicle immediately at the tail 

 of the epididymis and passes obliquely upward and forward, 

 to come in contact with the vascular cord in the inguinal 

 canal. 



