WITHIN MALE REPRODUCTIVE STRUCTURES 



183 



(4) the possibility of a weak sperm motility aiding the advance of the 

 sperm through the body of the epididymis must not be denied; 



(5) the vigorous pumping action of the vas deferens, especially during 

 the stimulation attending ejaculation, serves to transport the sperm 

 from the "epididymal well" (the cauda epididymidis) through the vas 

 deferens to the external areas. 



2. Transportation of Sperm in Other Vertebrates with a 

 Convoluted Reproductive Duct 



The transportation of sperm in other vertebrates which possess an extended 

 and complicated reproductive duct similar to that of the mammal presumably 

 involves the same general principles observed above (fig. 105A, B). However, 

 certain variations of sperm passage exist which are correlated with structural 

 modifications of the accessory reproductive organs. For example, the repro- 

 ductive duct may be somewhat more tortuous and complicated in some in- 

 stances, such as in the pigeon, turkey, and domestic cock (figs. 102, 105B). 

 That is, the entire deferent duct extending from the epididymis caudally to 

 the cloaca may be regarded as a sperm-storage organ, as sperm may be col- 

 lected in large numbers all along the reproductive duct. As the cock is 

 capable of effecting repeated ejaculations over an extended period of time, 



LUMEN 



GLAND-LIKE 

 OUT POUCHING S 

 OF MAIN LUMEN 



FOLDS OF 

 MUCOSA 



Fig. 101. Portion of a cross section of the ampullary region of the ductus deferens in 

 man. Observe gland-like outpouchings of the main lumen and character of mucosal folds. 

 Surrounding the lumen may be seen the highly muscularized walls of the ampullary area. 



