THE GENITOURINARY APPARATUS. 



267 



month,, carrying before it a fold of peritoneum, which is after- 

 ward shut off, forming the tunica vaginalis testis. Other cover- 

 ings of the testicles are also derived in this manner. In the 

 female a structure similar to the gubernaculum forms the round 

 ligament. 



The vas deferens has three coats (1) an external fibrous 

 coat, (2) an unstriated muscular coat, and (3) a lining mem- 



FIG. 126. 



The testicle and epididymis: A, testis; B, epididymis; C, tunica 

 vaginalis; D, vas deferens; E, spermatic artery and veins; F, artery 

 of cord. 



brane of columnar epithelium. It is about one and one-half feet 

 long and one line in diameter. From the tail of the epididymis 

 it ascends in the cord, forming an important part, and lyinu 

 behind the blood-vessels. It ascends through the inguinal canal, 

 and at the internal ring descends on the bladder, crosses the 

 ureter and obliterated hypogastric artery, and runs forward to 

 form with the duct of the seminal vesicle the ejaculatory duct. 



