THE MALE ORGANS OF GENERATION 



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in each organ varies from two hundred and fifty to four 

 hundred. In each lobule are convoluted seminiferous 

 tubules, varying in number from one to three. The coats 

 of the testes are : the tunica vaginalis externus, an external 

 coat derived from the peritoneum; the tunica albuginea, 

 formed of white, fibrous tissue, surrounding the gland and 

 reflected into its interior to form an incomplete partition 

 from which septa are given off, separating the gland into 



FIG. 157. Diagram representing the male genital apparatus of right 

 side: A, bladder; B, prostatic urethra; C, membranous urethra; D, 

 spongy urethra; i, Right testicle; 2, epididymis; 3, vas deferens, with 3, 

 its ampulla; 4, seminal vesicle ; 5, ejaculatory duct opening at the verumon- 

 tanum ; 6, Cowper's gland ; 7, its excretory duct (Testut). 



lobes ; the tunica vasculosa, or pia mater testis, consisting of 

 a plexus of blood-vessels covering the inner surface of the 

 tunica albuginea. 



The epididymis is a convoluted tube, some 20 feet long, 

 lying along the posterior border of the testes, being 

 formed by a convergence of the efferent vessels of the 

 seminiferous tubules of the testes, and terminating in the 

 vas deferens or excretory duct of the testes. This duct, 



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