198 Mr. J. McClelland on Indian Cyprinidae. 



tions of the two groups cannot be made out. The only Indian 

 Bream I am acquainted with (Cyp, cotis, Buch.) has the cha- 

 racter of the Perilamps both in the form of its mouth and 

 length of its alimentary canal ; while, on the other hand, the 

 old genus Leuciscus is not a natural group, some of the Euro- 

 pean species, as Cyprinus cultratus, being doubtless an Op- 

 sarins*, while others are certainly herbivorous f, and might 

 perhaps be referred to the Gudgeons ; but until all these 

 points be settled, it would be idle to dwell further on the par- 

 allel relations between the typical and subtypical groups. 



52. Cyprinidae, of all fishes of equal importance, are those 

 that appear to have occupied least the attention of naturalists ; 

 a circumstance the more curious, as, in consequence of their 

 being peculiar to fresh waters, they are more universally dis- 

 tributed in the interior of continents, where they ought to be 

 more familiar and useful to man than any other family of the 

 same class. 



Regarding their distribution, little has hitherto been made 

 known. It would not appear that there is any one species 

 common to Europe and America ; it is not however to be sup- 

 posed that we are yet prepared to form an accurate compari- 

 son between the Cyprinidce of the Old and New Worlds, since 

 the majority of species in either seems as yet to be but ill 

 defined. Nor is it to be supposed that ichthyology has yet 

 been prosecuted in America to an extent at all likely to make 

 us acquainted with the numerous species that must inhabit 

 the extensive lakes and rivers of that continent. Of African 

 species, few only are referred to by Cuvier, while the Nile is 

 known to present some species that are not found in the south 

 of Europe. The Chinese species may yet be said to be al- 

 most unknown, with the exception of a few determined by 

 Cuvier from the very doubtful data aiforded by paintings; 

 although it is seldom that so favourable an opportunity is 

 afforded for collecting information on any branch of natural 

 history as that which the British embassies in China pos- 

 sessed for investigating the peculiarities of the freshwater 

 fishes of that empire, from the length of time they passed in 

 boats on some of the principal rivers. Nor is anything what- 



* Leuciscus cceruleus, Yavrell, and L. erythrophthalmus, Cuv., appear to be 

 Perilamps; L. doublet,, L. Lancasirietisis, Yarr., and L. alburnus are also 

 insectivorous. I have mentioned this in a letter to Mr. Swainson in October 

 last, and I have no doubt the hint will be sufficient to direct the attention 

 of this philosophical naturalist to an examination of the whole of the English 

 species. 



f Leuciscus vulgaris, L. idus and L. rulilus are probably herbivorous, and, 

 according to the length of their intestine, may either be added to one or 

 other of the groups here indicated. 



