THE CAT 221 



tubules and produce the spermatozoa. The testis is closely in- 

 vested on its convex surface by a fold of the peritoneum, which 

 here forms a very deep, narrow pocket extending into the scrotum 

 from the abdominal cavity, with which the testis is joined by the 

 long, white spermatic cord. This cord extends from the inguinal 

 canal and is made up of the slender anterior portion of this peri- 

 toneal pocket— the lumen of which is, however, obliterated in 

 the cat— and the vas deferens, the blood vessels and nerves of the 

 testis, which give the cord its solid appearance; these form the 

 connection between the testis and the organs of the abdominal 

 cavity. When we remember that the testes have migrated from 

 their original position near the kidneys, through the inguinal canal 

 to the scrotum, carrying the vasa deferentia, their nerves and 

 blood vessels with them, we can understand how the spermatic 

 cord has come into existence. 



On the medial surface of the testis and at its two ends is a 

 white, bandlike mass of convoluted tubes. This is the epididymis, 

 the beginning of the efferent duct of the testis. It is composed 

 of three parts : the caput epididymis, which caps the anterior end 

 of the testis; a band extending from the caput along its inner 

 side to the posterior end ; and the cauda epididymis, the enlarged 

 posterior end. 



The caput epididymis is joined with the seminiferous tubules 

 of the testes by minute vessels called the vasa efferentia. The vas 

 deferens begins at the cauda epididymis, passes forward with 

 many convolutions along the inner side of the testis, and finally, 

 as a part of the spermatic cord, passes through the inguinal canal 

 into the abdominal cavity and to the neck of the bladder. Sur- 

 rounding the ends of the vasa deferentia is the bilobed prostate 

 gland. About an inch back of this gland are the paired Cowper's 

 glands, directly back of which the urethra enters the penis. This 

 structure is formed of three elongated cylindrical bodies, the 

 median ventral corpus spongiosum, through which the urethra 

 runs, and two lateral corpora cavernosa. The latter diverge to 

 the right and left at their proximal ends and form the crura penis. 

 The distal end of the penis is formed by the greatly enlarged end 

 of the corpus spongiosum and is called the glans penis ; a fold of 



