400 



PRACTICAL ANATOMY. 



invests the cord, having been carried before the testis in 

 its descent. The tunica vaginalis is a fold of peritoneum 

 pushed before the testis ; after birth its connection with 

 the abdominal peritoneal cavity is obliterated. It invests 

 the testicles and lines the interior of the scrotal pouch. 



The testes are suspended by the spermatic cord, which 

 are formed of arteries, veins, nerves, lymphatics, and the 



FIG. 171. SPERMATOZOA. 



1, human (X 600), the head seen from the side ; 2, on edge ; k, head ; m, middle piece ; 

 f, tail ; e, terminal filument ; 3, mouse ; 4, bothriocephalus latus ; ">, deer ; 6, mole ; 7, green 

 woodpecker; 8, black swan; 9, from a cross between a goldfinch (m) and canary (f) ; 10, 

 cobitis. 



vas deferens or excretory duct of the testicle. These 

 structures conjoin at the internal abdominal ring, and 

 pass along the inguinal canal to the testis. The testes are 

 ovoidal in form, about one and three-fourths inches long, 

 and weigh about an ounce each, and each is surmounted 

 by a tail-like body, the epididymis, which consist of 

 a body and the globus major (the head) above; the 

 globus minor (the tail) below, The testis is invested 



