REPRODUCTION. 



693 



the testicle to its lower border. This tube is known as the epididymis. 

 The seminal tubule consists of a basement membrane lined by granular 

 nucleated epithelium. 



The vas deferens, the excretory duct of the testicle, is about 60 cm. in 

 length and from 2 to 3 mm. in diameter, and extends upward from the 

 epididymis to the inguinal canal, through which it passes into the abdominal 

 cavity and then to the under surface of the base of the bladder, where it 

 unites with the duct of the vesicula seminalis to form the ejaculatory duct. 



The vesiculse seminales are two lobulated pyriform bodies, about 40 

 mm. in length, situated on the under surface of the bladder. Each vesicula 

 seminalis consists of an external fibrous coat, a middle, muscular coat, and an 

 internal mucous coat. The mucous coat contains a number of small 

 tubular albumin-producing glands which secrete a characteristic fluid. 



FIG. 348. DIAGRAM OF A VER- 

 TICAL SECTION THROUGH A TES- 

 TICLE, i. Mediastinum testis. 2, 

 2. Trabeculae. 3. One of the 

 lobules. 4, 4. Vas a recta. 5. 

 Globus major of the epididymis. 

 6. Globus minor. 7. Vas def- 

 erens. (Holden.} 



FIG. 349. VAS DEFERENS, VESICULSE 

 SEMINALES, AND EJACULATORY DUCTS. 

 a. Vas deferens. b. Seminal vesicle. 

 c. Ejaculatory duct. d. Termination of 

 the ejaculatory duct. e. Opening of the 

 prostatic utricle. /, g. Veru montanum. 

 h, 1. Prostate. (Liegeois.) 



The ejaculatory duct, formed by the union of the vas deferens and the 

 duct of the vesicula seminalis, opens into the prostatic portion of the urethra 

 (Fig. 349). 



The prostate gland is a musculo-glandular mass surrounding the 

 posterior extremity of the urethra. It contains a large number of tubules, 

 more or less branched and convoluted, and lined by columnar epithelium. 

 They secrete a fluid which is poured into the urethra at the time of the ejac- 

 ulation of semen and impart motility to the spermatozoa or spermia. 



The penis consists of three parts: the corpus spongiosum below, through 

 which passes the urethra, and the two corpora cavernosa, one on either side 

 and above. The corpus spongiosum terminates anteriorly in a conic- 



