THE VISCERA. 243 



last again involves itself in a serous sac (tun. vaginalis propria testis). The 

 tnbuli semiferi commence in blind (or looped T) extremities, at the periphery 

 of the testicle, and form, by means of their many short convolutions, a dense 

 cortical layer, which consists of from one to two hundred lobules (which un- 

 folded measure about from one thousand to one thousand two hundred feet 

 long). The lobules are supported by processes from the tunica albuginea, 

 which at the posterior border of the testicle forms a triangular space, corpus 

 Highmori, and continues inwards. From this corp. Highmori the tubuli pass 

 almost directly straight, when they have passed away from the lobules, and 

 then unite at an acute angle into a rete, rete vasculosum Halleri. From these 

 arise from nine to thirty vasa efferentia testis, which perforate the superior 

 extremity of the Corpus Highm., and pass into the head of the Epididymis. 

 They are many times convoluted, present (each) a conical cord, conus vasci^ 

 losus Halleri, the point of which is directed downwards, and they finally unite 

 to form the Canal of the epididymis. 



The seminal tubules consist (like the urinary) of a structureless membrane, 

 have a diameter of Oil to 0'24 of a line, and contain the Spermatic filaments 

 (spermatozoa) and the other elements of the Semen. 



b. The Epididymis s. parastata cirsoides, is the vermiform 

 appendix, two and a half to three inches long, which is placed 

 along the posterior border of the testicle somewhat externally, of 

 a brownish red, and flattened from above to below. Its thicker 

 and broader superior extremity, caput epididymis, rests with its 

 concave surface close upon the superior extremity of the testicle ; 

 the central part, corpus, is surrounded all round by tun. vaginal. ; 

 the inferior thinner and narrower portion, cauda, is again situated 

 close on the inferior extremity of the testicle, and continues, 

 curved downwards, into the vas deferens. 



Structure. The epididymis consists of a single tube, O12 to O33 lines in 

 diameter, and so often convoluted that its length measures thirty-two feet 

 (Monro), and is a continuation of the coni vasculosi. which coalesce in the caput 

 epididymis. Vasculum aberrans Halleri is a still more minute canal than that 

 of the epididymis, which passes upwards from the tail of the last to the vas 

 deferens, and is then lost ; it arises from the departure of a few seminal vessels 

 in the endeavour to form a second epididymis; according to Weber similar 

 blind canals are sometimes present in the duct, hepatic, and pancreatic. 



Vessels of the testicle : Jlrt. and V. spermatica interna; the veins arise from 

 the plexus pampiniformis. 



Lymphatics: plexus spermaticus. 



Nerves: plexus spermaticus (from pkx. renalis n. sympatici). 



Tunica vaginalis propria testis, the serous envelope (Perito- 

 nsRum) of the testicle, is a completely closed sac, in which it is 

 involved (like the lungs in the pleura), so that the one (internal) 

 layer (t. serosa testis or visceral) is connected firmly with the 

 testicle (t. adnata), the other (external) surrounds it loosely [t. 

 vaginalis reflexa or parietal], and a cavity is found between the 

 two, in which a serous fluid is exhaled. The reflection of the 

 external layer upon the testicle takes place at its posterior border, 

 at the corpus Highmori. The epididymis is separated from the 



