464 



TUBE-BLADDERED GROUP. 



latter species may be easily recognised by the keeled upper surface of the tail 7 

 and the projecting muzzle ; while the zope is characterised by the great elongation 

 of the anal fin, which commences opposite to the dorsal, and extends nearly to the 

 tail, combined with the oblique direction of the cleft of the mouth. 



GROUP OF BREAM. 



White Bream, Zope, Zarthe, and Common Bream {\ nat. size). 



Rapfen. 



By this name is known in Austria the typical representative 

 (Aspius rapax) of a small genus of carps, containing four species 

 from Eastern Europe and China, and somewhat intermediate in structural 

 characters between the breams and the bleaks. Agreeing with the former in the 

 shortness of the gill-rakers, these fishes always have the lower jaw projecting 

 considerably beyond the upper, which is but slightly protractile; the anal fin 

 never has less than thirteen rays ; and the sharp lower edge of the abdomen 

 behind the pelvic fins is crossed by the scales. Common in Eastern and Northern 



