UROGENITAL SYSTEM 

 n. 



813 



Ov. 



Fig. 457. 



II. Diagrammatic representation of the modifications of the 

 urogenital ducts. 1, 2, male and female Newt. 3, a tubule of 

 the kidney. 4, Male Frog. 5, Male Toad. 6, Male Bombinator 

 (European Frog). 7, Male Discoglossus (Fire-bellied toad). 

 8, Male Alytes (obstetrical toad), d, artery entering and produc- 

 ing a coil in the Malpighian body, M; B, Bidder's organ; 

 ef.s.c., efferent segmental canal ; F.B, fat-body ; gl, glomerulus ; 

 K, kidney ; l.c.c., longitudinal collecting tubule ; M, Malpighian 

 body ; Md, Miillerian duct ; N, nephrostome ; O, ovary ; ov, ovi- 

 duct ; s.d., segmental duct ; T, testis ; Ur, ureter ; V.d., vas 

 def erens ; V.8., seminal vesicle. (After Gadow.) 



and Wolffian body, while usually taking place at the cephalic end of the 

 mesonephros, may, as in some of the lung fishes, take place at the caudal 

 end. 



At about this time the glomeruli of the tubules degenerate. This 

 means that the part of the mesonephros in which these glomeruli de- 

 generate is no longer excretory, but has become a part of the repro- 



