290 NORMAL HISTOLOGY AND ORGANOGRAPHY. 



the fimbriated end of the Fallopian tube in the 

 female. The other is less constant and lies usually 

 just external to the globus major and is called the 

 stalked hydatid. It is an epithelial body and repre- 

 sents vestiges of the peritoneal end of the pronephric 

 or Wolffian duct. The stalked hydatid is also 

 present in the female, where it resembles a small 

 cyst closely associated with one of the fimbriae of the 

 Fallopian tube. 



The distance passed by the spermatozoa, before 

 being eliminated by the urethra, is approximately 

 twenty-four feet. The chief ducts and their lengths 

 are: seminiferous tubules, each two feet long; epi- 

 didymis, twenty feet; and vas deferens, two feet. 

 The spermatozoa are themselves perfectly inactive 

 in making this passage. During the copulation act 

 they are discharged probably from the whole length 

 of the vas deferens by peristaltic contraction of this 

 duct, and not only from the seminal receptacle as 

 formerly supposed. The supply of spermatozoa 

 is extensive. If each testicle has eight hundred 

 seminiferous tubules, each two feet long, then there 

 are sixteen hundred feet of epithelial lining for each 

 organ engaged in the production of spermatozoa. 

 The semen consists of a fluid part, secreted mainly 

 by accessory reproductive glands, and cell elements 

 or spermatozoa that develop in the testes. In man 

 there are about sixty thousand spermatozoa to each 

 cubic millimeter of semen. 



Vessels and Nerves. The spermatic artery supplies 

 the tubules of the testicles and the epididymis with 

 blood directly from the abdominal aorta. It is a 



