466 TUBE-BLADDERED GROUP. 



elongate, with the scales of moderate size, and the lateral line running below the 

 middle of the tail. The fins are generally similar to those of the last genus ; and 

 the lower jaw projects more or less beyond the upper, which is protractile. In 

 the hinder part of the abdomen the scales do not extend across the sharp lower 

 edge. Generally about 4 or 5 inches in length, and never exceeding 7, the 

 common bleak is steel-blue in colour above, with silvery white sides and under 

 surface, and the dorsal and caudal fins grey, the others being colourless. It is 

 found in rivers, lakes, and ponds, preferring clear water; and in calm, warm 

 weather swimming rapidly about near the surface in search of flies and other 

 insects. During the spawning-season, which is in May and June, bleak collect in 

 large shoals, which are preyed upon not only by perch, but likewise by gulls 

 and terns. 



Nearly allied to the bleak is a small fish (Leucaspius delineatus) from the 

 rivers of Eastern and Southern Europe, distinguished by the extreme shortness of 

 the lateral line, which scarcely extends beyond the extremities of the pectoral fins. 

 The scales also are of a regular ovate form, without the distinct fan-like rays so 

 characteristic of the bleak. 



The last member of this great subfamily that we shall mention 



is the curious-looking fish (Pelecus cultratus) shown in the upper 

 figure of the illustration on p. 465, known in Germany as the sichel, and forming 

 the sole representative of its genus. It is at once characterised by the whole of 

 the abdominal surface of the oblong and compressed body forming a sharp cutting 

 edge ; the scales being small, and the lateral line making a sudden descent behind 

 the pectoral fin towards the lower surface. The cleft of the mouth is always 

 peculiar in having a nearly perpendicular direction. The pectoral fins are 

 unusually tall, and the dorsal is placed far back, and above the anal, which 

 resembles that of the bream in its numerous rays. On the pharyngeal bones the 

 teeth are arranged in a double series, and are strongly hooked. In profile this 

 fish, which generally ranges from 6 inches to a foot in length, is remarkable for 

 the straightness of the line of the back, and the convexity of its lower border. It 

 is widely distributed in Eastern Europe, being common in the Black and Caspian 

 seas, as well as in their affluent rivers. In form this fish makes a curious approach 

 to the members of the herring tribe. 



With the small fishes known as loaches, of which there are three 



European genera, we come to the second subfamily (Cobitince) of 

 the carp tribe, which is characterised by the air-bladder being either partially or 

 entirely enclosed in a bony capsule; false gills being always absent. In these 

 fishes the body may be elongate, oblong, compressed, or cylindrical, but is never 

 depressed ; the muzzle and lips are fleshy ; and the small, inf eriorly-placed mouth 

 is furnished with from six to twelve barbels. The median fins are spineless, the 

 dorsal having a variable number of rays, but the short anal possessing but few, 

 while the pelvic pair may be wanting ; scales small, rudimental, or absent, and when 

 present, cycloid, and usually immersed in mucus ; in one Oriental genus, developed 

 upon the back and sides of the head. The loaches of this subfamily are confined 

 to Europe and Asia ; and while some of those from the former continent are 

 partial to swift clear streams with a stony bottom, the Indian forms delight in- 



