806 



MALE ORGANS OF GENERATION. 



convex border looks forwards and downwards, the posterior or straight border, 

 to which the cord is attached, backwards and upwards. 



The anterior and lateral surfaces, as well as both extremities of the organ, 

 are convex, free, smooth, and invested by the tunica vaginalis. The posterior 

 border, to which the cord is attached, receives only a partial investment from 

 that membrane. Lying upon the outer edge of this border, is a long, narrow, 

 flattened body, named, from its relation to the testis, the epididymis (tiSvpo^ 

 testis). It consists of a central portion, or body, an upper enlarged extremity, 

 the globus major, or head; and a lower pointed extremity, the tail, or globus 

 minor. The globus major is intimately connected with the upper end of the 

 testicle by means of its efferent ducts; and the globus minor is connected with 

 its lower end by cellular tissue, and a reflection of the tunica vaginalis. The 

 outer surface and upper and lower ends of the epididymis are free and covered 

 by serous membrane; the body is also completely invested by it, excepting 

 along its posterior border, and connected to the back of the testis by a fold of 

 the serous membrane. Attached to the upper end of the testis, or to the epi- 

 didymis, is a small pedunculated body, the use of which is unknown. 



Size and Weight. The average dimensions of this gland are from one and a 

 half to two inches in length, one inch in breadth, and an inch and a quarter in 

 the antero-posterior diameter; and the weight varies from six to eight drachms, 

 the left testicle being a little the larger. 



The testis is invested by three tunics, the tunica vaginalis, tunica albuginea, 

 and tunica vasculosa. 



The Tunica Vaginalis is the serous covering of the testis. It is a pouch of 

 serous membrane, derived from the peritoneum during the descent of the testis 

 in the foetus, from the abdomen into the scrotum. After its descent, that por- 

 tion of the pouch which extends from the internal ring to near the upper part 



of the gland becomes obliterated, the lower por- 

 tion remaining as a shut sac, which invests the 

 outer surface of the testis, and is reflected on the 

 internal surface of the scrotum; hence it may be 

 described as consisting of a visceral and parietal 

 portion. 



The visceral portion (tunica vaginalis 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 on to the inter- 

 nal surface of the scrotum. 



The parietal portion of the serous membrane 

 (tunica vaginalis reflexa} is far more extensive 

 than the visceral portion, extending upwards 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 squamous 

 epithelium. The interval between the visceral 

 and parietal layers of this membrane constitutes 

 the cavity of the tunica vagiualis. 



The Tunica Albuginea, is the fibrous covering 

 of the testis. It is a dense fibrous membrane, of a bluish-white color, composed 

 of bundles of white fibrous tissue, which interlace in every direction. Its outer 

 surface is covered by the tunica vaginalis, except along its posterior border, 

 and at the points of attachment of the epididymis; hence the tunica albuginea 

 is usually considered as a fibro-serous membrane, like the dura mater and peri- 

 cardium. This membrane surrounds the glandular structure of the testicle, 

 and, at its posterior and upper border, is reflected into the interior of the gland, 



Fig. 438. The Testis in Situ. 

 The Tunica Vagiualis having been 

 laid open. 



Mtcry 

 of Cvrd 



