ANATOMY OF VESICULA SEMINALIS. 



523 



The mucous membrane is thrown into ridges by the bending of the tube, 

 and presents an areolar or honeycomb appearance ; it is provided with 

 tubular glands, as in the vas deferens, and is covered by a flattened epi- 

 thelium. 



End of vas deferens (fig. 178). Opposite the vesicula the vas deferens 

 is increased in capacity, and is rather ^acculated like the contiguous vesi- 

 cle : but before it joins the tube of that body to form the common seminal 

 duct, it diminishes in size, and becomes straight. In the mucous lining 

 are numerous tubular glands like those of the intestine (Henle) ; and the 

 epithelium is columnar as in the rest of the tube. 



Fig. 178. 



a. Bladder. 



b and c, right and left lateral lobes of the 

 prostate. 



d. Middle lobe. 



e. Vesicula seminalis, the right one un- 



ravelled. 

 /. Vas deferens. 

 g. Common seminal duct, formed by the 



union of the vas deferens with the 



duct of the vesicula. 

 h. Ureter. 



VIEW OF THE UNDER PART OF THE BLADDER WITH THE VESICULA SEMINALES AND 

 VASA DEFERENTIA (Slightly altered from Haller). 



Common seminal ducts (fig. 180, /). These tubes (right and left) are 

 formed by the junction of the narrowed part or duct of the vesicula semi- 

 nalis with the vas deferens of the same side. They begin opposite the 

 base of the prostate, and are directed upwards and forwards through an 

 aperture in the circular prostatic fibres, and along the sides of a hollow 

 (vesicula prostatica), to open into the urethral tube. Their length is 

 rather less than an inch, and their course is convergent to their termina- 

 tion close to each other in the floor of the urethra (p. 527). 



Structure The wall of the common duct is thinner than that of the 

 vesicula seminalis ; but it possesses similar coats. It is surrounded by 

 longitudinal involuntary muscular fibres, which blend in the urethra with 

 the submucous stratum. It possesses the same glands and epithelium as 

 the dilated part of the vas deferens; but at the end of the tube the 

 mucous membrane wants glands and is smooth (Henle). 



