260 THE VISCERA. 
sac, enveloped in the membranes or tunics described when 
treating of the scrotum. Lach is attached to the dorsal wall 
of its peritoneal pouch by a mesenteric fold. The testis is sur- 
rounded by the visceral layer of the tunica vaginalis propria, 
and within this, by a dense fibrous covering, the tunica albu- 
ginea, which sends septa into its interior. Within the fibrous 
covering it is made up of numerous coils of seminiferous tubules 
which are readily seen by the naked eye. 
The epididymis (Fig. 110, ¢) is the beginning of the 
efferent duct of the testis. It appears as a flat band with a broad 
rounded end which lies on the medial surface of 
the testis at its cranial end (4). From this 
point it passes about the cranial end of the testis 
from its medial to its lateral surface, forming 
thus a semicircle with. the convexity ventrad. 
Thence it passes as a narrower band (c) along 
the dorsal side of the testis, laterad of the sus- 
pending mesentery, to the caudal end of the 
testis (7). At the caudal end of the testis it 
is enlarged, passes from its lateral to its medial 
surface, and turns at the same time craniad to 
become continuous with the vas deferens (e). 
The enlarged cranial end is the caput epi- 
Fic. 110.—Trsris, didymis (4) ; the enlarged caudal end the cauda 
a, testis; 4, caput Cpididymis (@). The whole epididymis is 
epididymis; ¢, epi- encased in a tough fibrous covering similar to 
didymis; d, cauda i 
epididymis; ¢, vas that of the testis. The fibrous covering (albu- 
eee sP*t- pinea) of the testis and that of the epididymis 
are connected by fibrous tissue. Within the 
fibrous covering the head of the epididymis is made up of tubules 
which pass from the testis into its end: these are the vasa 
efferentia testis. The vasa efferentia unite within the caput 
into a single vessel which passes in a very tortuous course to 
the cauda. Its numerous windings form the cauda, from the 
end of which it passes craniad as the vas deferens (ec). 
The vas deferens (Fig. 110, ¢; Fig. 111, ¢) is a slender 
tube much convoluted at its beginning. It passes from the 
cauda epididymis (@) along the mesenterial fold of the testis 
