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HANDBOOK OF PHYSIOLOGY. 



soon begins to assume a relatively lower position in the body; the ovaries 

 being ultimately placed in the pelvis; while toward the end of foetal 

 existence the testicles descend into the scrotum, the testicle entering 

 the internal inguinal ring in the seventh month of foetal life, and com- 

 pleting 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 



Fig. 515. Diagram showing the relations of 

 male (the right-hand figure $ ) reproductive org 

 these organs in the higher verte-brata (includii 

 bladder; U, ureter; K, kidney; U h, urethra; 

 body; W d, Wolffian duct ; M, Mullerian duct ; 1 

 corpus spongiosum ; C c, corpus cavernosum. 



In the female. P", vagina; U , uterus; F p. 

 ovarium ; A, anus ; C c, C s p, clitoris. 



In the male.Csp, C c, penis; U t , uterus 

 deferens. (Huxley.) 



the female (the left-hand figure 9 ) and of the 

 ans to the general plan (the middle figure of 

 ig man). C I, cloaca: R, rectum: B Z, urinary 

 , genital gland, ovary, or testis; W, Wolffian 

 's t, prostate gland; Cp, Cowper's gland; Csp, 



Fallopian tube; G t, Gaertner's duct; Pv, par- 

 masculinis; Fs, vesicula seminalis; F"d, vas 



the tunica vaginalis or serous covering of the organ; the communica- 

 tion between the tunica vaginalis and the cavity of the peritoneum being 

 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 are compelled 

 to accompany it, so to speak, 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 dis- 

 tributed. 



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



