458 



COMPARATIVE ANATOMY 



FIG. 344. KIDNEY OF Discoyfossu* jiir/ti*. From the ventral surface, showing 



the nephrostomes (St). (After J. "W. Spengel.) 

 Ur, urinogenital duct, enlarging at I'/- 1 to form a seminal vesicle. 



Proteus), 1 but it usually becomes swollen distal ly and is often 

 bilobed : in Alytes and Bombinator it forms a double sac. 



1 In Amphiuma, it is relatively very lung. In the < Jymnophiona, the Madder 

 presents certain pecidiar secondary modifications. 



