854 



TEE GENERATIVE APPARATUS. 



border, to the testicular or spermatic cord ;' a thick funiculus contained in the 

 middle portion of the vaginal sheath, and formed by the aggregation of the 

 spermatic vessels with the vas deferens. 



This cord is itself sustained in the sheath by the fraenum that unites the 

 two serous tunics of that cavity. 



Steuctueb. — Independently of the serous tunic that covers the exterior 

 of the testicle, there enter into its structure a fibrous membrane, tissue proper, 

 and vessels and nerves. The excretory duct will be studied separately. 



Fibrous Membrane. — This membrane, designated the tunica albuginea, 

 forms a strong resisting shell around the testicle, and its texture is 

 channeled by sinuous spaces which lodge the large spermatic vessels. It 

 is covered by the visceral layer of the tunica vaginalis, to which it closely 

 adheres ; its inner face sends thin septa into the proper substance of the 

 gland, which divide the latter into the spermatic lobules. Towards the 

 upper border of the testicle, and in front, the tunica albuginea is slightly 

 thickened; this part is named the corpus Sigmori (01 mediastinum testis), 

 and at this point the seminal ducts pass through it to reach the epididymis. 



(This membrane is dense and inelastic, being composed of white fibrous 

 tissue interlacing in every direction.) 



Tissue proper. — The proper substance 



Fig. 397. 



of the testicle resembles a 

 greyish-yellow pulp, contained 

 in the tunic albuginea ; it is 

 divided by the prolongations 

 which that tunic sends into its 

 interior into small distinct 

 lobules (lobuli testis), independ- 

 ent of each other. These 

 lobules vary in number, from 

 two to three hundred, and all 

 have the same organisation, 

 each being constituted by two 

 or three extremely convoluted 

 filiform tubuli, about from one 

 to two yards in length. These 

 tubes, the tubuli seminiferi, 

 anastomose frequently with 

 each other near their extremi- 

 ties, twine together, and can be 

 unwound like a ball of thread. 

 One of their extremities ter- 

 minates in a cul-de-sac, the 

 other being detached from the 

 lobule, and enters a central 

 system of excretory ducts which 

 ■will be referred to imme- 

 diately. 



When -we cut through a tes- 

 ticle vertically and lengthways, 

 . . . , , , , . so as to divide the corpus Eiqh- 



mon mto two lateral portions, there is seen in its substance a whitish 



^Jr "^" ^^F^l^ aTiatomy, there is sometimes included in the spermatic cord the middle 

 funLr vaginalis and all its envelopes— the serous, fibrous, and erythroid 



A TESTICLE (hIJMAN) INJECTED WITH MERCURY. 



a, a, Lobules formed of seminiferous tubes ; i, Eete 

 testis ; c, Vasa efferentia ; d, Flexures of the efferent 

 vessels passing into the head, e, e, of the epididy- 

 mis ; /, Body of the epididymis ; g. Appendix ; h, 

 Cauda : i Vas deferens 



