246 



CLASSIFICATION OF FISHES. 



{Salmo Eperlanus), is longest; but^ in all other respects, 

 the head of this fish is a compound of Salmo and 

 Laurida, — two genera widely separated by Cuvier, but 

 which actually pass into each other in the most gradual 

 manner: the SaJmo fcBtans (W^och., pi. 384. f. 2.) brings 

 us, in fact, at once into the genusLaurida [LauridaMe- 

 diterranea Nob., fig. 48.), the peculiar and discriminat- 



ing character of which is, that the ventral fin is so much 

 developed as to be considerably larger than the pec- 

 toral, near to which it is placed^ — and not, as in Salmo, 

 immediately under the first dorsal. Some of the Lau- 

 ridcE of America (jL. microps,fig. 49-) have the eyes very 



small, and the teeth (a) crooked and hooked, or, rather, 

 half barbed; the mouth being excessively wide: while the 

 jaws in others are unequal. In all, however, the sides 

 of the head are covered with scales, and the ventral fin 

 is very large. For convenience we may retain the sub- 

 genus Aulopus, although it consists of but a single 

 species, and has such a close resemblance in most parts 

 of its structure to Laurida, that it seems to us to 

 belong to the same generic group. M. Cuvier supposes 

 this fish to connect the salmons with the cods ; but we 



