198 Anatomy of the Rabbit. 



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



of vessels, the plexus pampiniformis, which surrounds the 



internal spermatic artery in its posterior portion. It opens 



forwards into the inferior caval at the angle formed by the 



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



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



Owing to the open communication of the testis sac with the abdom- 

 inal cavity, the association of the ductus deferens with the spermatic 

 vessels to form a spermatic cord (funiculus spermaticus) is very 

 imperfectly expressed. 



2. The connections of the deferent ducts with the common 

 urinogenital tube and related parts may be displayed, by dividing 

 the symphysis 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, by 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 white fibrous cord, the crus penis. The latter is 

 partly concealed by a short thick ischiocavernosus muscle, 

 the origin of which occupies a similar position on the ischium. 

 The penis is also attached, to the symphysis by a short but stout 

 suspensory ligament (lig. suspensorium) and by a thick spindle- 

 shaped pubocavernosus muscle lying between the ischiocaver- 

 nosi. 



The attachments of the penis should, be severed, at the posterior 



border of the ischium and the symphysis divided. By pressing 



apart the two sides of the pelvis the urinogenital tubes, with the 



penis and the pelvic portion, of the rectum, may be dissected out 



and removed from the body. 



The middle haemorrhoidal artery (a. haemorrhoidalis media), a branch 

 of the hypogastric, passes to the side of the rectum, to the urethra, and to the 

 seminal vesicle. The internal pudendal artery (a. pudenda interna), accom- 

 panied by the corresponding nerve ami vein, passes to the side of the penis, giving 

 off the inferior haemorrhoidal artery to the terminal portion of the rectum 

 and to the associated rectal or anal gland. The rectum is connected with the 

 root of the tail by the rectocaudalis muscle, a somewhat spindle-shaped 

 aggregation of smooth muscle fibres, arising from the body of the second caudal 

 vertebra, and inserted a short distance forwards on the dorsal surface of the 



