524 PHTSOSTOMI. 



Family, V— CYPRINIDiE. 



Branchiostegals three: pseudobranchiae generally present. Body oblong or elongated: abdomen 

 usually rounded, but, if compressed and cutting, destitute of ossicles. Margin of the upper jaw formed by 

 the pre-maxillaries. Opercles in four pieces. Mouth toothless, but from one to three rows of teeth in the 

 inferior pharyngeal bones, which latter are strong, free, and parallel to the branchial arches. A single, rayed 

 dorsal fin. Head scaleless,* body scaled or scaleleas, never covered by osseous plates. No " cul de sac" to the 

 stomach, nor pyloric appendages. Air-vessel, if present, large ; it may be divided by a constriction into an 

 anterior and posterior portion, neither of which are enclosed by bone (Gyprinvrm) ; or into two lateral portions, 

 partially or entirely enclosed in a bony capsule, (GoMtidmce). 



Geographical distribution. — Carps are found in the fresh waters of the Old World and North America. 



The family of carps (Gyprinidce) are wpU represented amongst the piscine inhahitants of the fresh waters 

 and estuaries of India, Ceylon, and Burma, as they and the Siluridce compose the great mass of fish residing 

 there, especially if we do not include the migratory Glwpeidce. 



Whereas siluroids as a rule appear to prefer muddy water, carps seem to thrive better in those which 

 are clear, still many species of this family obtain their subsistence in dirty waters, for which purpose their 

 birbels may prove of considerable assistance. 



There are few members of this family which are such foul feeders as the Siluroids, consequently Carps 

 may be deemed more wholesome and would be greatly preferable, were it not for the numerous bones with 

 which they are provided. Natives however do not seem to much object to this, and as these fish are very 

 abundant in places, they enter largely into the diet of the indigenous population. 



Indian carps do not appear to restrict themselves so much to a vegetable diet as do those in Europe, for 

 in the Tropics an eternal and destructive war is constantly being carried on between the different races of the 

 animal kingdom. Those which prey upon their neighbours, as might be anticipated, are largely represented : 

 whilst amongst those that were apparently produced to be preyed upon, it is mostly only the most prolific which 

 have survived. 



In the sub-family Oyprinince, as existing in Asia, considerable difficulty arises in selecting a division into 



groups. 



In forming such, a very distinctive characteristic may be found by observing whether the scaled 

 edge or margin of the abdomen is rounded or cutting, for in the majority of the Indian Gyprinince the 

 abdominal edge is rounded or smooth, even when somewhat compressed : whilst in a few genera the abdominal 

 edge posterior to the ventral fin is compressed, cutting, and may even be serrated, as in the Glupeidoe : this 

 trenchant edge is in some continued from in front of the ventral fins along the thorax. 



Irrespective of the . above, there are many other characters which might be employed for forming 

 sub-groups and genera. In some, however, which might at first appear suitable for such purposes, one fails to 

 attach that significance to their presence when large numbers of species come under review, showing the 

 existence of connecting links. Some of these characters may be external, others are internal. 



The mouth is variously formed ; it may be transverse and Inferior, with or without a sucker, the latter 

 being present either on the lower lip or existing on both ; or it may be narrow, of medium size, or wide : 

 anterior, and either antero-lateral or oblique. The lower jaw again may be prominent, sharp or rounded, 

 shorter than the upper, or sometimes having a knob at the symphysis ; a moveable articulation may exist there, 

 or there may be lateral prominences on the mandibles. 



The lips may be exceedingly, moderately, or but slightly developed, sometimes absent from one of the 

 jaws, closely investing both, or reflected from off one, or either. There may be an uninterrupted labial fold 

 across the mandible, or portions of the lip may be much developed, fringed, or crenulated. In some genera, a 

 horny or cartilaginous covering to one or both lips is invariably or generally present, especially in forms from 

 the Hills. 



The existence of a transverse groove across the snout can scarcely be distinctive of a species, much less 

 of a Genus. Thus in Biscognathus lamta we find examples with rounded and smooth snouts, and all inter- 

 mediate forms to such as the one figured Plate cxxii, f. 1. The same may be seen in Laheo nukta and several 

 fishes of that Genus, and even in some species of Barhus, as B. dorsalis. The nearer the hills the more is this 

 groove developed. 



" Genus LeptoboUa, Bleeker, from China forms an exception, its preopercnlar region having some rows of small scales. 



