INDIAN CYPRINID^. 



255 



50. It would be too much to expect from the materials of one zoo- 

 logical province to demonstrate satisfactorily all the properties of natural 

 groups in the minor divisions of this family. That its typical and sub- 

 typical groups are circular is plain enough, from the diminution in the 

 length of the intestinal canal we experience in passing from the Cirrhins 

 to the Barbels ; and again, from the Barbels through the Gonorhynchs to 

 the Gudgeons that canal becomes longer, indicating an union between tlie 

 latter, and the group from which we set out. 



The same thing is observed in passing from the Systoms through 

 the Opsarions, Perilamps, and Leuciscs; a tendency between the former and 

 latter to unite is indicated, thus forming the sub-typical group (Sarcoborince) 

 into a circle. 



A similar thing may be seen in the aberrant group ( Apaloptermce ) in 

 which the Schisturce form one extremity, and the Platycara the other ; the 

 intermediate space being occupied with the Pcscilimice, Psilorhynchi, and true 

 Loaches. The entire caudal of the former points out their relation to Cohitis 

 prop., but until analysis be extended to all known species, European and 

 American, the attempt to reduce the smaller groups to any thing like pre- 

 cision would be difficult and uncertain, from the greater chance there is of the 

 series being less complete than in the higher groups, of which Ave might 

 always hope to possess at least a specimen of each genus. 1 shall therefore 

 content myself with having submitted the preceding tabular view of the 

 })rincipal group, referring to the elucidation of genera for further details, 

 in the confident expectation tliat what has already been demonstrated will in- 

 duce naturalists to investigate the subject from the materials of other countries 

 as well as of tliis. 



We are far from being prepared to point out tht> most characteristic 

 types even of our Indian groups of this family. Indeed there may yet 



