882 



GENERATION. 



The course of the vas deferens is in the spermatic cord to the external abdominal 

 ring, through the inguinal canal to the internal ring, where it leaves the blood-vessels, 

 passes beneath the peritoneum to the side of the bladder, then along the base of the 

 bladder by the inner side of the seminal vesicle, finally joining the duct of the seminal 

 vesicle, the common tube forming the ejaculatory duct, which opens into the prostatic 

 portion of the urethra. 



The walls of the vas deferens are thick, abundantly supplied with vessels and nerves, 

 and provided with an external fibrous, a middle muscular, and an internal mucous coat. 

 The greater part of that portion of the tube which is connected with the bladder is dilated 

 and sacculated. The fibrous coat is composed of strong connective tissue. The muscular 

 coat presents three layers ; an external, rather thick layer of longitudinal fibres, a thin, 

 middle layer of circular fibres, and a thin, internal layer of longitudinal fibres, all of the 

 non-striated variety. By the action of these fibres, the vessel may be made to undergo 

 energetic peristaltic movements, and this has followed galvanization of that portion of 

 the spinal cord corresponding to the fourth lumbar vertebra, which is described by Budge 

 as the genito-spinal centre. 



The mucous membrane of the vas deferens is pale, thrown into longitudinal folds in 

 the greatest part of the canal, and presents numerous additional rug& in the sacculated 

 portion, these rug& enclosing little, irregular, polygonal spaces. The membrane is cov- 

 ered with columnar epithelium, which is not ciliated. In the sacculated portion, are 

 numerous mucous glands. 



Attached to the vas deferens, near the head of the epididymis, is a little mass of con- 

 voluted and sacculated tubes, called the organ of Giraldes, or the corpus innominatum. 



This body is from to % of an inch long and 

 -^z of an inch broad. Its tubes are lined with 

 cells of pavement-epithelium, which are often 

 filled with fatty granules. Generally, the tubes 

 present only blind extremities, but some of 

 them occasionally communicate with the tubes 

 of the epididymis. This organ has no physio- 

 logical importance. It is regarded by Giraldes 

 as a remnant of the Wolffian body, analogous 

 to the parovarium. 



Vesiculm Seminales. Attached to the base 

 of the bladder and situated externally to the 

 vasa deferentia, are the two vesicul semi- 

 nales. These bodies are each composed of a 

 coiled and sacculated tube, from four to six 

 inches in length when unravelled, and some- 

 what convoluted, in the natural state, into an 

 ovoid mass which is firmly bound to the vesical 

 wall. The structure of the seminal vesicles is 

 not very unlike that of the sacculated portion 

 of the vasa deferentia. They have an external 

 fibrous coat, a middle coat of muscular fibres, 

 and a mucous lining. Muscular fibres pass 

 over these vesicles from the bladder, both in a longitudinal and in a circular direction, 

 and serve as compressors, by the action of which their contents may be discharged. The 

 mucous coat is pale, finely-reticulated, and is covered with cells of polygonal epithelium, 

 nucleated and containing brownish granules. No mucous glands have been found in its 

 substance. 



The vesiculas seminales undoubtedly serve, in part at least, as receptacles for the 



FicK 283. Vas deferens, vesicular serninales, and 



qjaculaiory ducts. (Lie, r eois.) 

 a, vas deferens ; 6, seminal vesicle ; c, ejaculatory 



duct ; c7, termination of the ejaculatory duct ; 



, opening of the prostatic utricle ; /, g, varu 



montanum ; A, I, prostate. 



