The American Representatives of Distouium cygnoides. 421 



this species is the iirinary bladder of the Bull Frog {Eana 

 cateshiana). 



The European species, Gorgodera cygnoides (Zeder), in size, 

 sliape, suckers, position of intestinal cseca etc., most closely re- 

 sembles Nos. 2 and 3. Tlie multiple testes clearly distingiiisli it. 



