464 
TUBE-BLADDERED GROUP. 
latter species may be easily recognised by the keeled upper surface of the tail, 
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 
