SEX IN LIVING FORMS 115 



ANATOMY OF THE REPRODUCTIVE 

 ORGANS 



Having now considered the functions and something 

 of the structure of the principal organs of reproduc- 

 tion, we may obtain a more definite idea of the relation 

 of the several organs of each class by a connected re- 

 view of the anatomy of the parts. 



Male Organs.— As previously stated, the external 

 organs of generation in the male are the penis and the 

 testicles, the latter being contained in a pouch, called 

 the scrotum. The penis is the organ of urination as 

 well as of copulation. Its structure is cellular, and it 

 contains a vast number of minute coils of blood-ves- 

 sels, which become turgid with blood under the in- 

 fluence of sexual excitement, producing distention and 

 erection of the organ. A canal passes through its en- 

 tire length, called the urethra, which conveys both the 

 urine and the seminal fluid. The organ is protected by 

 a loose covering of integument, which folds over the 

 end. This fold is called the foreskin, or prepuce. 



The fluid formed by each testicle is conveyed by the 

 vas deferens, a curved tube about two feet in length, to 

 the base of the bladder. Here the vas deferens joins 

 with another duct, which communicates with an elon-- 

 gated pouch, the vesicula seminalis, lying close to the 

 under side of the bladder. The single tube thus formed, 

 the ejaculatory duct, conveys the seminal fluid to the 

 urethra, from which it is discharged. 



As the production of seminal fluid is more or less 

 constant in man and some animals, while its discharge 

 is intermittent, the vesiculae seminales serve as reser- 

 voirs for the fluid, preserving it until required, or 

 allowing it to undergo absorption. Some claim that 



