860 DEVELOPMENT. [CH. LVIII. 



In the male, the Miillerian ducts have no special function, and 

 are but slightly developed. The hydatid of Morgagni is the 

 remnant of the upper part of the Miillerian duct. The small 

 prostatic pouch, uterus, masculinus, or sinus pocularis, forms the 

 atrophied remnant of the distal end of the genital cord, and is, 

 therefore, the homologue, in the male, of the vagina and uterus 

 in the female. 



We must now pass to the development of the ovary and testis. 



Between the Wolffian body and the mesentery, the mesoblast 

 covering the ridge produced by the projecting Wolffian body, is 

 converted into a thick epithelium called the germ epithelium (see 

 fig. 679). From this the reproductive gland (ovary or testis as 

 the case may be) is developed. 



The manner in which the ovary is formed is described in out- 

 line in Chapter LVII. (p. 802) ; the testis is formed in a similar 

 way, only the downgrowths of cells which become nests of cells to 

 form ova and Graafian follicles in the female, become hollowed 

 out as seminiferous tubules in the male. 



For some time it is impossible to determine whether an 

 ovary or testis will be developed ; gradually however the special 

 characters belonging to one of them appear, and in either case 

 the organ soon begins to assume a relatively lower position in 

 the body ; the ovaries are thus ultimately placed in the pelvis ; 

 while towards the end of foatal existence the testicles descend 

 into the scrotum, the testicle entering the internal inguinal ring 

 in the seventh month of foetal life, and completing its descent 

 through the inguinal canal and external ring into the scrotum by 

 the end of the eighth month. A pouch of peritoneum, the 

 processus vaginalis, precedes it in its descent, and ultimately forms 

 the tunica vaginalis or serous membrane of the organ ; the com- 

 munication between the tunica vaginalis and the cavity of the 

 peritoneum is closed only a short time before birth. In its 

 descent, the testicle or ovary of course retains the blood-vessels, 

 nerves, and lymphatics, which were supplied to it while in the 

 lumbar region, and which accompany it as it assumes a lower 

 position in the body. Hence the explanation of the otherwise 

 strange fact of the origin of these parts at so considerable a 

 distance from the organ to which they are distributed. 



Descent of the Testicles into the Scrotum. The means by which 

 the descent of the testicles into the scrotum is effected are not 

 fully and exactly known. It was formerly believed that a mem- 

 branous and partly muscular cord, called the gubernaculum testis, 

 which extends while the testicle is yet high in the abdomen, from 

 its lower part, through the abdominal wall (in the situation of 



