LEPUS CUNICULUS 



32i 



is 



B 



body, but it is a compact discrete organ. Then, too, the tubules 

 do not possess nephrostomic funnels opening into a lymph cavity 

 as we find in the mesonephros of Rana ; and, lastly, the ureter i' 

 also a separate structure, not 

 related in any way to the old 

 segment al duct. 



The essential male re- 

 productive organs are the testes. 

 In the embryo these are situated 

 on the latero-dorsal abdominal 

 wall just behind the kidneys, 

 and like them are asymmetrical, 

 the right lying in front of the 

 left. As the animal reaches 

 maturity, however, they migrate 

 backwards and finally lie in 

 extensions of the body cavity, 

 the scrotal sacs, which appear 

 externally as small pouch-like 

 projections of the body wall in 

 the perineal region. The aper- 

 ture joining the cavity of the 

 sac to the abdomen is termed 

 the inguinal canal, and the two 

 cavities are always in open 

 communication through it. Of 

 course the testis was attached 

 to the body wall in its original 

 position by a fold of peri- 

 toneum, and there, too, it 

 received its vascular and ner- 

 vous connections. These ob- 

 viously could not be broken, 

 and so we find a strand of 

 connective tissue with a nerve, 

 an artery and a vein, attached to each testis and passing up 

 through the inguinal canal to the primitive position of that body. 

 The strand so formed is termed the spermatic cord. 



The testes themselves are oval pinkish- white bodies lying wholly 

 within the scrotal sacs ; it is possible, however, to pull them through 

 the inguinal canal into the abdominal cavity by means of the 

 spermatic cord, but in so doing the scrotal sac will also be inverted, 

 since they aie attached to its posterior wall. Attached along the 

 inner side of each testis is an irregular convoluted tubular mass, 



Y 



FIG. no. Diagram of male urogeni- 

 tal system of Lepus. 



A., anus ; B. ; urinary bladder ; C., Cowper's 

 gland ; C.S., corpus spongipsum ; B.C., caput 

 epididymis ; E.Ca., cauda epididymis ; G., guber- 

 naculum ; K., kidney ; P., penis ; Pe., perineal 

 gland ; Po., prostate gland ; Pr., prepuce ; P.S., 

 pelvic symphysis ; R., rectum ; R.G., rectal 

 gland ; S.C., spermatic cord ; S.S., scrotal sac ; 

 T., testis ; U., ureter ; U.M., uterus masculinus ; 

 Ur., urethra ; V.D., vas deferens. 



