246 



THE MALE REPRODUCTIVE SYSTEM 



is thinner than the circular coat. Outside the muscle coat there is 

 an adventitia of fibrous tissue in which there are groups of smooth 

 muscle cells. As the vas deferens continues into the body cavity, 

 a connective-tissue extension of the adventitia supports the sper- 

 matic artery, spermatic vein, nerves, and a plexus of veins, called 



Muscularis 



^W^mm 



-Miicom 



Fig. 151. — Diagram of the vas defereiLS of a mammal. 



Fig. 1.52. — Photograph of a section through the spmiual vesicle of the rat. 



the pampiniform plexus, the whole being called a spermatic cord. 

 The ampulla at the distal end of the vas deferens has large ridges 

 in tlic tunica ])roi)ria, and in its walls are glandular outpocketings. 

 Seminal Vesicles. Each seminal vesicle is an elongated, lol)uIated, 

 twisted irregular sac, with an adxciititia coutiuuous witli that of 



