CHAP, x.] THE DEVELOPMENT OF THE CAT. 



353 



Fig. 158. DIAGRAM OF THE DEVELOPMENT OF GENERATIVE ORGANS. THE BODY is SUPPOSED TO 

 BE CUT THROUGH VERTICALLY, AND THE URINARY AND GENERATIVE ORGANS OF THE 

 LEFT SIDE TO BE VIEWED LATERALLY. 



A. The earliest or neutral condition, the sexual 



gland (sg) being as yet undifferentiflted into 

 either ovary or testis, and the Wolftian 

 body (w) and duct (wd), and the Mullerian 

 duct (/), all co-existing with the permanent 

 kidney (fc) and ureter (tit], the papilla (rp) on 

 the ventral side of the opening of the 

 urethra (uli) being rudimentary. 



B. Here the neutral state is changing into the 



complete female condition. The sexual 

 gland (sgo) has become an ovary. The 

 Wolftian body and duct (w and ivd) have 

 almost aborted. The remnant of the 

 Wolftian body (w) has become the par- 

 ovarium and Gaertner's duct. The Mul- 

 lerian duct OH) has expanded and opened at 

 its free end, and become a Fallopian tube, 

 the lower end of which has coalesced with 

 its fellow of the opposite side to form the 

 vagina (v) and uterus (us). The opening 

 of the cornu of the right side is seen at oc. 



C. Here the neutral state is changing into the 

 complete male condition. The sexual 

 gland (s(jt) has become a testis, and has 

 travelled backwards and downwards into 

 the scrotum (s) its original position being 

 indicated by dotted lines. The Mullerian 

 duct (m) is reduced to a rudiment, the pros- 

 tate has developed (pg), and the rudimentary 

 papilla has become a relatively large organ 

 ( p), which is represented as truncated. 



a. Anal aperture, al. Allantois. &. Bladder. 



c. Clitoris. fc. Kidney. m. Muller's duct. 



oc. Opening of right uterine cornu into uterus. 



lj. Prostate gland. 



rp. Rudimentary papilla, which becomes the 

 penis in the male. 



s. Scrotum. 



sg. Undifferentiated sexual gland. 



sgo. Ovary. sgt. Testis. uh. Urethra. 



vs. Uterus. tit. Ureter. v. Vagina. 



IP. Wolfflan body. v.<d. Wolffian duct 



A A 



