240 CLASSIFICATION OF FISHES. 



tropical latitudes. They have, says Cuvier, ^^ all the 

 characters of Erythrinus," except that their dorsal and 

 anal fins, both long and narrow, are placed close to the 

 tail : he arranges them with the Clupeince ; but they 

 seem to us more naturally related to Cypi'inus and 

 Salmo. The last genus, Sudis, is remarkable for its 

 lengthened cylindrical body, covered with large osseous 

 scales, indicating its analogy to the chelonifonn fishes, 

 and to the flat-headed SiluridcB : its mouth opens some- 

 what vertically, as in Chironectes and Uranoscopus ; and 

 on these grounds we suspect it is the type of all these 

 fishes in the present sub-family: only three species have 

 yet been found. 



(215.) The SalmonmcE, or salmons, have many close 

 relations to the carps ; nevertheless their larger mouth, 

 their thin lips, and well-defined teeth, show that their 

 food and economy are very different. In this division are 

 arranged all such fishes of this family as have a small 

 adipose dorsal fin. placed half-way between the first 

 dorsal and the caudal. We do not feel confident, how- 

 ever, for reasons hereafter stated, that this is a tinily 

 natural arrangement ; although, in the present state of 

 ichthyology, it is a, very convenient one for discrimi- 

 nating the genera. The different groups of salmon are 

 distributed more abundantly in the Old than in the New' 

 World : the history of those that are common to our 

 own country has been repeated so often as not to require 

 notice in this place. The salmon, salmon trout, and 

 chars are well known for their rich and delicate flavour: 

 the first, more especially, produces a source of much 

 wealth to those concerned in its fishery. 



(216.) It is evident, that if Erytlirmus is to be 

 placed among the carps, on account of its single dorsal 

 fin, it must be an aberrant type ; and whether we ulti- 

 mately assign it to that circle, or to the one now before 

 us, it forms a link of connection between the two. There 

 are two or three very remarkable sub-genera of fluvia- 

 tile fish in the rivers of Tropical America, which seem to 

 have as much of the aspect of perch as of salmon : they 



