Fig. 401. 



THE MALE GENITAL ORGANS. 859 



"head of the epididymis or globus major. The posterior, the tail of the epidi- 

 dymis, or globus minor, is more detached from the testicle, and is curved 

 upwards to be continued by the deferent canal (vas deferens). 



STRUCTURE. The epididymis is constituted by a long duct doubled a 

 great number of times on itself, and whose convolutions, after injection with 

 mercury, can be very readily seen through the serous membrane. This 

 duct results from the union of from twelve to twenty small tubes, the 

 efferent ducts, which, arising from the rete testis, open together, at a variable 

 distance, into the globus major. Towards the globus minor there is only 

 one duct, which is more voluminous and less flexuous, and finishes by 

 becoming detached from the posterior lobe of the epididymis to constitute 

 the vas deferens. 



The organisation of the walls of these ducts is not the same throughout. 

 Thus, in the efferent ducts, it comprises a simple ciliated epithelium, resting 

 on a proper amorphous membrane, which again is placed on unstriped 

 circular fibres attached to a thin fibrous tunic; while beyond, there is 

 observed a stratified ciliated epithelium, a proper membrane, two layers of 

 unstriped fibres circular and longitudinal and also a fibrous tunic. The 

 thickness of the muscular layers increases from before to behind. 



The epididymis receives its arteries and nerves from the same sources 

 as the testicle. t 



DEFERENT CANAL (vas deferens). This duct is about the thickness of a 

 goose- quill, and is at first flexuous, then 

 straight. It lies parallel with, but behind 

 and to the inner side of, the spermatic vessels, 

 as far as the opening of the tunica vaginalis ; 

 passing through this opening, it enters the 

 pelvic cavity, and crosses obliquely the ureter 

 and obliterated cord of the umbilical artery. 

 It is then inflected backwards, placed above 

 the bladder, suddenly dilates, and is prolonged 

 as far as the neck of that reservoir, where it 

 terminates; after having penetrated beneath 

 the prostate gland by a sudden contraction, 

 at the origin of which, and outwardly, the 

 vesicula seininalis opens, and is continued 

 by the ejaculatory ducts. 



The vas deferens is sustained in the 

 tunica vaginalis by a very short serous fold, 

 a dependency of the fraenuni, whose two lay- 

 ers envelope the spermatic vessels, within 

 and behind which this duct is situated. In 

 the abdominal cavity, it is fixed by the pro- 

 longation of this serous duplicature. Its 

 dilated or pelvic portion is in contact, 

 superiorly, with the vesiculae seminales, and 

 is finally united to its dilated homologue of the opposite side, which it 

 has been gradually approaching, by means of a triangular peritoneal fold, 

 that comprises between its two layers a small club-shaped cavity which 

 will be alluded to again. 



The calibre of the vas deferens is very small in its vaginal and abdo- 

 minal portions, but is greater towards the pelvic dilatation, where the walls 

 of the duct offer a well-marked areolated disposition. 



DIAGRAM OF THE TESTICLE 



(HUMAN). 



Mediastinum testis, containing 

 the rete testis ; 2, 2, Trabeculi ; 

 3, One of the lobules ; 4, 4, Vas 

 recta ; 5, Globus major ; 6, Globus 

 minor ; 7, Vas deferens. 



