The; Urinogenital System. 129 



abdominal wall, forms the internal lining of the sac of the 

 testis (of. p. 51). The sac is widely open to the abdominal 

 cavity, so that the testis passes freely from one cavity to the 

 other. 



(b) The male reproductive gland, the testis, with its associated 

 vessels and duct, occupy the cavity of the sac, the testis 

 being suspended from its dorsal wall. 



(c) The gubernaculum, a short thick cord containing smooth 

 muscle fibres, joins the posterior end of the testis with the 

 end of the sac. 



(d) The visceral layer (lamina visceralis) of the tunica vaginalis 

 propria forms the peritoneal coat of the testis and is con- 

 tinuous with the mesorchium, a broad vertical fold of peri- 

 toneum connecting the testis forwards with the dorsal body- 

 wall. 



(e) The first portion of the duct of the testis, the epididymis, 

 forms a thickened mass at the anterior end of the testis, and 

 extends backward as a thinner cord along its side. The 

 thickened anterior portion is the caput epididymidis and 

 the contracted posterior portion tlie Cauda epididymidis. 

 The second portion, the ductus deferens, leaves the testis at 

 its posterior end, where it is firmly attached to the guberna- 

 culum. The connection with the epididymis may be shown 

 by carefully separating the duct from the gubernaculum 

 and the side of the testis. 



(f) The internal spermatic artery (a. spermatica interna) arises 

 from the abdominal aorta, that of the left side immediately 

 behind the origin of the inferior mesenteric. It enters the 

 anterior end of the testis. 



(cr) The spermatic vein (v. spermatica) is formed by a network of 



"^ vessels, the plexus pampiniformis, which surrounds the 



internal spermatic arterv in its posterior portion. It opens 



forwards into the inferior caval at the angle formed by the 



latter with the renal arterv. (That of the right side enters 



the inferior caval at about the level of the spermatic arteries.) 



Owincr to the open communication of the testis sac with the abdominal 



the association of the ductus deferens with the spermatic vessels to form 



a spermatic cord (funiculus spermaticus) is very imperfectly expressed. 



'> The connections of the deferent ducts with the common urino- 

 genltal tube and related parts mav be displayed by dividing the sym- 

 phvsis and dissecting in the interior of the pelvis. The structure and 

 attachments of the penis should first be examined. 



Apart from its terminal portion, the glans penis, and the urethra, the 

 body of the penis is chiefly formed of a pair of hollow fibrous structures, 

 the cavernous bodies (corpora cavernosa penis). Each of these is firmly 

 attached to the posterior margin of the ischium by a fibrous cord, the 

 crus penis. The latter is largely concealed by a short thick ischiocaver- 



