458 ANATOMY FOR NURSES [Chap. XXI 



(2) The epididymis is a long, narrow body which Hes along the 

 posterior portion of the testicle and consists of a tortuous tubule, 

 which is lined with mucous membrane, and contains some muscular 

 tissue in its walls. If unravelled it is found to be about twenty- 

 feet (5 metres) long. It connects the testicle proper with the vas 

 deferens. 



Function. — The function of the testes is the production of sper- 

 matozoa. These spermatozoa are the essential part of the seminal 

 fluid. The spermatozoa originate in the cells of the testes lining 

 the tubules which compose the bulk of the testes. An internal 

 secretion is also supposed to be formed here. 



Descent of the testes. — In early fcetal life the testes are 

 abdominal organs lying in front of and below the kidneys. Dur- 

 ing the process of growth they are drawn downward through 

 the inguinal canal and shortly before birth are normally found in 

 the scrotum. Sometimes, particularly in premature infants, the 

 testis is found in the inguinal canal or even in the abdominal 

 cavity ; as a rule it soon descends and occupies its proper posi- 

 tion ; but occasionally it does not descend and an operation is 

 necessary. 



The vas deferens. — The vas deferens is a continuation of the 

 epididjinis, and is the excretory duct of the testicle. After a very 

 devious course it joins the duct of the seminal vesicle at the base of 

 the bladder. It consists of three coats, an external areolar, a 

 middle muscular, and an internal mucous coat. 



The seminal vesicles. — The seminal vesicles are two pouches 

 which are placed each one on the outer side of each vas deferens, 

 between the bladder and the rectum. They are pyramidal in form, 

 with the broad ends directed backward and widely separated. 

 The anterior portions converge, become narrowed, and unite on 

 either side with the corresponding vas deferens to form the ejacu- 

 latory duct. 



Function. — The seminal vesicles serve as a reservoir for the 

 semen, to which they add a secretion of their own. 



The ejaculatory ducts. — The ejaculatory ducts are two in niun- 

 ber, one right and the other left. They are formed by the union 

 of the seminal vesicle and vas deferens of each side. They run 

 downward and converge as they descend, enter and pass between 

 the lobes of the prostate gland and open into the floor of the pros- 



