174 



THE ESSENTIALS OF HISTOLOGY 



The testicle is enclosed by a strong fibrous capsule, the tunica al- 

 buginea (fig. 209, e). This is covered externally with a layer of serous 

 epithelium reflected from the tunica vaginalis. From its inner surface 

 there proceed fibrous processes or trabeculce, which imperfectly sub- 

 divide the organ into lobules, and posteriorly the capsule is prolonged 

 into the interior of the gland in the form of a mass of fibrous tissue, 

 which is known as the mediastinum (fig. 209, h). Attached to the pos- 

 terior margin of the body of the gland is a mass (epididymis) which 

 when investigated is found to consist of a single convoluted tube, receiv- 



Iti- Ifm ]/> B f ml 



FIG. 211. PASSAGE OF CONVOLUTED SEMINIFEROUS TUBULES INTO STRAIGHT TUBULES 

 AND OF THESE INTO THE RETE TESTIS. 



a, seminiferous tubules ; 6, fibrous stroma continued from the mediastinum testis ; c, rete testis. 



ing at its upper end the efferent ducts of the testis and prolonged at its 

 lower end into a thick- walled muscular tube, the vas deferens, which 

 conducts the secretion to the urethra. 



The glandular substance of the testicle is wholly made up of convo- 

 luted tubules, which when unravelled are of very considerable length. 

 Each commences near the tunica albuginea, and after many windings 

 terminates, usually after joining one or two others, in a straight tubule 

 (fig. 211), which passes into the mediastinum,, and there forms, by 



