THE MALE ORGANS OF GENERATION. 231 



brane is connected externally by connective tissue with the 

 muscular layer of the scrotum, the dartos. 



The muscle of the scrotum, the dartos, consists of numerous 

 smooth muscular fibres, arranged singly or forming a more or 

 less continuous layer. 



The skin of the scrotum is peculiar in containing consider- 

 able pigment, while there is an absence of fat in the subcu- 

 taneous tissue. Hairs, large sebaceous follicles, and sweat- 

 glands are also present in the skin of the scrotum. 



The Tiydatid of Morgagni is a structure found upon the 

 anterior surface of the head of the epididymis, and is thought 

 to be the remains of Miiller' s duct. It is met with in two 

 forms, either as a vesicle containing a clear fluid (with cells, 

 and nuclei ciliated epithelial cells are also at times present), 

 and connected to the epididymis by a solid fibrous peduncle, or 

 as a flattened structure possessing scarcely any stalk, which 

 is simple or divided into lobules ; the latter form is most fre- 

 quently seen. At times it is found to communicate with the 

 canal of the epididymis. 



Between the head of the epididymis and the vas deferens, 

 situated upon the posterior edge of the testicle, a small organ 

 is seen, consisting of several whitish nodules. Each nodule is 

 composed of a tube forming a number of convolutions and ter- 

 minating in a club-shaped extremity. The tubes contain a 

 clear fluid and are lined by a cylindrical epithelium, the cells 

 of which are undergoing degeneration. Until ten years of age 

 this organ is fully developed ; after this period it experiences 

 degeneration. This structure is known as the organ of Gir- 

 aldes, and represents the remains of the Wolflian bodies. 



The glandular or parenchymatous structure of the testicle 

 consists of canals or seminiferous tubules about 0.1128 to 

 0.1421 mm. in diameter ; they are folded on themselves sev- 

 eral times so as to constitute lobules, and are situated in the 

 spaces formed by the trabeculse of the tunica albuginea. The 

 tubules not only are folded but divide and subdivide, anasto- 

 mose, and terminate by loops. Toward the apices of the lob- 

 ules the tubules gradually become more straight, fewer in 

 number, and pass into the corpus Highmori, forming the 

 rete test is. From the upper part of the rete emerge twelve to 

 seventeen larger tubules which pass through the tunica albu- 

 ginea, after which they again become convoluted and form a 



