CARP TRIBE. 459 



anal scales not enlarged, and the eye unprovided with a fatty lid ; while they are 

 specially characterised by the arched mouth — which is devoid of internal folds — and 

 by the presence of false gills. The anal fin is frequently tall, the lips are devoid of 

 any horny covering, and the barbels, if present, may be either two or four in 

 number. The scales may be either small or very large, and the body is frequently 

 of a much more elongated form than in the true carps. While some species are 

 not more than 2 inches in length, the mahasir, and some other kinds, may grow 

 to at least 6 feet. Of the Indian forms, Day writes that those with four barbels 

 (among which is the mahasir), " provided they are soberly coloured, attain a large 

 size ; the brilliantly coloured forms are mostly residents in clear or rapid mountain- 

 streams, or rivers contiguous to hills, and generally small. A strong dorsal spine 

 is usually (if not invariably) a sign that the species lives in the vicinity of high 

 mountains, the streams of which it ascends to breed. An exception has, however, 

 to be made of those forms with serrated dorsal spines, which are usually resident 

 in the waters of the plains." The common barbel, which has four of the appendages 

 from which it derives its name, not uncommonly grows to a length of 2 feet, with 

 a weight of from 8 to 10 lbs., but may attain much larger dimensions. 



Confining; our attention mainly to the European representatives 

 Gudgeon. ° . . 



of the family, we have next to mention the gudgeons (Gobio), which 



may be distinguished from the foregoing by the pharyngeal teeth being arranged 

 in a double or single series ; the body being entirely covered with scales ; and the 

 muzzle having two small barbels, with the mouth inferior in position, and the 

 premaxillary bones protractile. The scales are of moderate size, the short dorsal 

 fin has no spine, and the intestine is remarkable for its shortness. These small 

 fishes are represented only by two species, of which G. fluviatilis is British; and, 

 like the barbels, they are purely animal-feeding. The British species is shown in 

 the lower figure of the illustration on p. 462. 



. From the whole of the members of the family noticed above the 



so-called " white-fish " belong to a group of genera in which the anal 

 fin is short or of medium length, with from eight to eleven branched rays, and not 

 extending forwards beneath the line of the dorsal ; the lateral line, when complete, 

 running nearly or quite in the middle of the tail. From certain allied forms they 

 are distinguished by the short dorsal fin having no bony ray ; and the pharyngeal 

 teeth form a single or double series, the margin of the lower jaw is not cutting, 

 and there are no barbels. As distinctive peculiarities of the white-fish may be 

 mentioned the protractile premaxillary bones, the imbricating scales, and the 

 smooth outer surface of the pharyngeal teeth. The numerous representatives of the 

 white-fish are distributed over the rivers of the North temperate zone, the New World 

 forms somewhat exceeding in numbers those of the Old. Among the European 

 representatives of the genus, the roach (Leuciscus rutilus), shown in the right- 

 hand middle figure of our illustration, agrees with several other species in having 

 a single series of pharyngeal teeth, at least ten rays in the anal fin, and the dorsal 

 nearly opposite the pelvic fins ; its deep body being silvery, and the lower fins of 

 the adult generally tinged with red. Its range is confined to Europe north of the 

 Alps. On the other hand, the chub (L. cephalus), shown in the lower figure of the 

 illustration, may be selected as an example of a second group in which there are two 



