THE VISCERA. 245 



c. Pars inguinalis, passes through the inguinal canal, inclin- 

 ing from below, upwards, from within, outwards and from before, 

 backwards, continues over the curvature of the art. epigastrica 

 forming a part of the spermatic cord. 



d. Pars vesicalis sinks downwards, at its exit from the inguinal 

 canal and the cord directly into the pelvis, over Vasa epigastricse, 

 at first on the side, then on the posterior surface of the urinary 

 bladder, where it crosses obliquely the Art. umbilicalis, and be- 

 takes itself inwards and downwards to the fundus vesicss before 

 the ureter, then passes transversely inwards to the inner side of 

 the vesiculse seminales, where both vasa deferentia almost meet 

 together, and join behind the prostata, with the anterior extremi- 

 ties of the seminal vesicles at an acute angle. Two inches above 

 the vesiculas seminales it is thinner and wider. 



Structure. Cylindrical, with thick walls, hard, narrow, and only at its 

 inferior extremity expanded ; this canal presents an extremely delicate, 

 white, and folded mucous membrane, surrounded by a compact contractile 

 coat, and an external uniting tissue. Muscular fibres exist in large animals 

 (horses) indubitably. Arter. : spermatica interna and vesical. ; very numerous 

 inwards towards the seminal vesicles. 



The spermatic cord,funiculus spermaticus, a looser cord at 

 the posterior part of the testicle, which, passing with and into the 

 testicle, through the inguinal canal as far as the internal ring, is 

 composed of the following parts, viz. : 



1. Vas deferens (with Art. and Ven. spermatica defcrens, from vesicalis in- 

 ferior; only sometimes) ; at the internal posterior part. 



2. Art. spermatica interna, on the anterior and external side of the vas de- 

 ferens. 



3. Ven. spermatic, interna, with plexus pampiniformis. 



4. Plexus spermatic, lymphaticus. 



5. Nerv. spermaticus extern, (branches of genito-cruralis\ Plex. spermatic, (n. 

 symphaticus). 



6. Habercula (the obliterated tunica propria testis), and sometimes 



7. Vasculum aberrans Halleri. 



The above mentioned parts are united by an adipose uniting tissue (tun. 

 propria funiculi), and they are held firmly together by the 



Tunica vaginalis communis testiculi et funiculi. This last 

 is a fibrous membrane, covered by m. cremaster, which surrounds 

 the tunica propria of the testicle, and is connected through the 

 inguinal canal with the uniting tissue between fascia transversa- 

 lis and peritoneum. (It becomes thicker and stronger from pres- 

 sure, e. g., of fluid.) 



479. 4. Fesiculse seminales s. spermaticae, 



two longish, flattened, irregular sacs, between the rectum and 

 bladder, along the external side of the vasa deferentia, lying at 

 the anterior extremity close to one another and diverging back- 



