384 - Multicellular Animals, Especially Man 

 BLADDER 



"WW/¥M. 



URETER 



SEMINAL 

 VESICLE 



PROSTATE GLAND 



VAS DEFERENS 



EPIDIDYMIS 



SCROTUM 



PELVIC 

 BONE 



URETHRA 



•PENIS 



TESTIS- 



ary sexual characteristics of the male (p. 

 399). 



In the frog and most other lower verte- 

 brates, the sperm pass through the kidney 

 before they reach the main gonoduct (Fig. 

 21-4). A number of fine ducts, the vasa effer- 

 entia, lead from the testis to some of the 

 nephric tubules in the kidney, and these 



rKtrUCb pig. 21-5. Genital organs of human male, 

 semidiagrammatic. Note connection with the 

 urinary tract, near origin of urethra. 



nephric tubules drain into the urogenital 

 canal. Moreover, the urogenital canal does 

 not lead to the exterior, but drains into the 

 cloaca. This terminal portion of the digestive 

 tract transmits the sperm, through the ex- 

 ternal opening to the environment. 



In man the sperm tract is very complex. 

 There are a number of vasa efferentia, which 



VAS DEFERENS 



Fig. 21-6. Human testis. Relations of 

 the epididymis to the seminiferous tu- 

 bules and vas deferens. (From Haggard, 

 The Science of Health and Disease. Per- 

 mission of Harper and Row.) 



glands OF 



INTERNAL SECRETION 



COMPARTMENT 

 OF TESTIS 



