The Male Genitalia 3 



down their peritoneal fold which extends from the guber- 

 naculum below the origin of the spermatic artery in the 

 lumbar region. It is attached anteriorly to the spermatic 

 cord and posteriorly to the scrotal wall, to form the mesor- 

 chium which constitutes a membranous median partition in 

 the posterior part of each scrotal sac from the fundus to the 

 internal inguinal ring, as shown in Figs. 2, 3, and 4. The 

 processus vaginalis, in everting, pushes before it on the 

 lateral side the as yet invisible cremaster which quickly de- 

 velops when the testicle descends into a bright red, highly 

 functioning muscle. The scrotal sac thus consists of two 

 distinct groups of tissues, the general integument composed 

 of the skin and dartos and the intra-abdominal portion con- 

 sisting of the parietal peritoneum and the cremaster muscle 

 with the intervening fasciae. The two groups of structures 

 remain easily separable throughout life. The surgeon in 

 performing the "covered operation," when castrating ani- 

 mals with scrotal hernia, avails himself of this distinction 



FlG. i.— The Testicle and its Attachments. 

 Right inguinal region and testicle of 24 hrs. colt. P, Processus vaginalis sur- 

 rounded by a dotted line and containing a curved sound, 5 ; G, first portion of 

 gubernaclum testis ; G', second portion of gubernaculum testis extending to the 

 epididymis,^ ; /■:, epididymis ; G", gubernaculum extending from epididvmi's (globus 

 minor) to the testicle ; T, testicle; A, testicular artery ; V, V, vasa de'ferentia ■ B 

 urinary bladder ; UA, umbilical arteries. 



