THE TESTICLES AND THEIR COVERINGS 



1381 



Tunica Vaginalis. 



Tunica Albuginea. 



Its Septa. 



didymis is another small, pear-shaped body the pedunculated hydatid (appendix 

 epididymidis). These bodies are the remains of embryonic structures. When 

 the testis is removed from the body, the position of the vas deferens, on the pos- 

 terior surface of the testis and inner side of the epididymis, marks the side to which 

 the gland has belonged. 



Structure of the Epididymis. The epididymis is surrounded by a capsule of white fibrous 

 tissue. The globus major consists of from ten to fifteen tubules, which are convoluted and lined 

 by stratified ciliated epithelial cells. The body and globus minor are composed of the convolu- 

 tions of a single tubule, which if straightened would measure upward of twenty feet. These 

 parts are lined by stratified ciliated cells and continue as the vas deferens. 



The Tunics of the Testicle. The testis is invested by two tunics the tunica 

 vaginalis and the tunica albuginea 



The tunica vaginalis (tunica vaginalis propria testis} (Figs. 1130 and 1133) 

 is the serous coverin'g of the testis and epididymis. It is a pouch of serous mem- 

 brane, derived from the peritoneum (processus vaginalis peritonaei) during the 

 descent of the testis in the 

 fetus from the abdomen into 

 the scrotum. After its descent 

 that portion of the pouch 

 which extends from the internal 

 ring to near the upper part of 

 the gland, the funicular process, 

 becomes obliterated, the lower 

 portion remaining as a shut 

 sac, which invests the outer 

 surface of the testis, and is re- 

 flected to the internal surface 

 of the scrotum; hence it may 

 be described as consisting of a 

 visceral and parietal portion. 



The visceral portion (lamina 

 visceralis] of the tunica vagi- 

 nalis propria covers the outer 

 surface of the testis, as well as 

 the epididymis, connecting the 

 latter to the testis by means 

 of a distinct fold. From the 

 posterior border of the gland 

 it is reflected to the internal 



surface of the infundibuliform process of the transversalis fascia, and between the 

 tunic and the fascia is a layer of unstriated muscle fibres, the Internal cremaster 

 muscle (Fig. 1125). 



The parietal portion (lamina parietalis) of the tunica vaginalis propria is the 

 reflected portion. It is far more extensive than the visceral portion, extending 

 upward for some distance in front and on the inner side of the cord, and reaching 

 below the testis. The inner surface of the tunica vaginalis is free, smooth, and 

 covered by a layer of endothelial cells. The interval between the visceral and 

 parietal layers of this membrane constitutes the cavity of the tunica vaginalis and 

 contains a small amount of serous fluid. 



The obliterated portion of the pouch may generally be seen as a fibrocellular 

 thread, the ligament of Cloquet (rudimentum processus vaginalis) (Fig. 1127), 

 lying in the loose areolar tissue around the spermatic cord; sometimes this may be 

 traced as a distinct band from the upper end of the inguinal canal, where it is 



Tubuli 



seminiferi 



contorti. 



Ductuli 

 efferentes. 



Tubuli 

 -seminiferi 

 recti. 



FIG. 1132. Vertical section of the testis, to show the arrange- 

 ment of the ducts. 



