18 CLASSIFICATION OF FISHES, 



(16.) The third genus of the PercincB is represented 

 by such fish as the Aspro of Cuvier, where the form is 

 more slender and elongated than in the true perch, the 

 head very much depressed, and the muzzle decidedly 

 advanced beyond the under jaw. It is easy to recog- 

 nise, in this form^ a representation of the curtilaginous 

 type, and of the Mugilidce : the ventral fins are much 

 developed, and are longer than the pectorals, — a structure 

 which also reminds us of the Gohiancp, or gobies. The 

 fourth genus is of the chironectiform type^ and is ad- 

 mirably represented by Huro. Its very wide mouth 

 opens in an obliquely vertical direction ; the under jaw 

 is longest ; and the first dorsal fin, as in Uranoscopus 

 and Trachinus (also chironectiform types), is very small. 

 The last generic group we place in this sub-family is 

 composed of Pojnatomus and Apogon, — both remarkable 

 for their excessively large eyes and thick head : the 

 scales are particularly large, and very deciduous : in both 

 the teeth are minute and velvety ; and both appear con- 

 fined to the Mediterranean and Red Seas. It will be 

 observed, that in Apogon the ventral fin, like that of 

 Ambassus (which seems the chironectiform type of this 

 genus), is before the pectoral, whereas in Pomatomus it 

 is beneath. It is therefore under the belief that Am- 

 bassus connects Huro with Apogon, that we have placed 

 it in the present group ; while the entire structure of 

 the sub-genus Cheilodipterus so beautifully unites those 

 of Apogon and Lucioperca, that we are almost at a less 

 to determine into which of the genera it enters. We 

 thus return to the genus from whence we commenced ; 

 and we find the sub-family of PercincB constitutes a 

 circle, of which the following table expresses the com- 

 ponent parts and the analogies : — 



Analogies of the Percin^, or Typical Perches. 



Genera of the a„„i^„„. Families of the 



PERCiNi. Analogies. MACROLEPTEa. 



Ferca. Body oblong ; mouth large. Percidje. 



EnopiCSUS. { ^fjan.°"' '"'""'^ ' ""'""' '^"^j CHiEXODONID*. 



