628 SPECIAL HISTOLOGY. 



According to Swan ("Nerves of the Human Body," PI. V., 82; VL, 

 81), the vas deferens within the pelvis is surrounded by numerous, but 

 fine nerves, which are in connection with those of the lateral and me- 

 dian, vesical and rectal nerves, as well as with those of the hypogastric 

 plexuses. I have myself also seen these nerves, which contain fine 

 fibres, and "fibres of Remak," but have been unable to trace them in 

 the interior. 



The structure of the ejaculatory ducts and vesiculce seminales appears 

 to be the same as that of the vasa defej'entia ; the seminal vesicles, as is 

 •well known, being nothing more than appendages of the latter, furnished 

 with wart-like, saccular, or even branched processes. The ejaculatory 

 ducts, in their upper portions, present the same muscular structure as 

 the spermatic canal, only that their walls are more delicate. As they 

 approach the prostate, their membranes become still thinner, but never- 

 theless, even at the ultimate extremity, exhibit muscular fibres, mixed 

 with a considerable quantity of connective tissue and elastic fibrils. The 

 walls of the vesiculce seminales are much thinner than those of the vas 

 deferens, although they possess the same structure, except that the mani- 

 festly vascular mucous membrane is furnished throughout with reticular 

 fossce. Externally, the vesiculce seminales are invested with a membrane, 

 in part composed solely of connective tissue, in part, as on the posterior 

 surface, distinctly muscular, which is continued between the separate 

 convolutions of its canal, connecting them together ; and, at the inferior 

 end, passes from one vesicula seminalis to the other, in the form of a 

 broad muscular band. The contents of the vesiculce seminales are, nor- 

 mally, a clear, rather viscid fluid, which after death acquires a soft gela- 

 tinous consistence, though subsequently it becomes perfectly fluid ; it 

 contains a protein-compound very readily soluble in acetic acid and 

 which is obviously identical with that contained in the ejaculated semen. 

 With many other observers, I have so frequently seen spermatic fila- 

 ments in the vesiculce seminales, that I should describe their occurrence 

 there as normal, and assign a double function to the seminal vesicles ; 

 together with its principal one, of afi"ording a special secretion, that of 

 also performing the part of seminal receptacles. The nerves of the vesi- 

 culce seminales are derived from the sympathetic, and spinal cord, imme- 

 diately from the rich plexus seminalis, the filaments of which, in part, 

 penetrate the membranes of the vesicles, though they cannot be traced 

 further, in part proceed to the 'prostate, whose plexus — plex2is prostati- 

 cus — receives additions also from the vesical and inferior pelvic plexuses. 



The prostate, according to my observations, is a very muscular organ, 

 so much so, that the glandular substance does not constitute more than 

 one third or a half of the whole mass. Proceeding from within to with- 

 out, there is presented in intimate connection with the thin mucous mem- 

 brane, the epithelium of which is always in two layers, though possess- 



