ANALOGIES OF THE ORDER. 



or salmons^ and the greater part of the true perches. The 

 shape of both these groups is that of a long oval^ mode- 

 rately thick^ without any extraordinary development of 

 any one part or member. These characters_, however_, 

 do not apply to the two next groups^ namely^ the Micro- 

 leptes and the Pleuronectidce : here the scales are inva- 

 riably very small, and often excessively minute. When 

 we consider the shape of the Zeidce, or dories (one of 

 the types of the Microleptes) , we may justly pronounce 

 them the flat fish of the acanthopterygious order j both 

 are short and excessively broad fish j both have the 

 scales very minute ; and both stand as the sub-typical 

 divisions of their respective orders. The ZeidcB, in 

 fact, are the shortest and most compressed fish of the 

 Microleptes, just as the Pleuronectidce are of the Mala- 

 copteryges. Passing from these, we come to the Gym- 

 netres, or riband-fish, which stand opposite, in our 

 table, to the GadidcB, or cods. That these two groups 

 are not only analogous, but actually pass into each 

 other, is completely proved on looking to the genera 

 Cepola and Ophidium in the first, and to Physis and 

 Raniceps in the second. In both we find the dorsal fin 

 excessively long, composed of numerous slender rays; 

 and the ventrals singularly varied, by being either very 

 small and fihform, or altogether wanting : the scales 

 likewise are minute, scarcely perceptible, and seem im- 

 bedded in the common skin of the body, which, from 

 being generally extended over the dorsals, renders those 

 fins very thick. Here, likewise, the spiny rays of the 

 two former tribes disappear, and are exchanged for 

 others, which, if not flexible, as in Ammodytes^ Ophi- 

 dium, Cepola, and all the Gadidce, are always very 

 slender and brittle. The Gymnetres, in fact, have lost 

 the distinguishing character of the Acanthopte7'yges, and 

 thus become as truly soft-rayed fishes as any of the 

 GadidcB. The resemblance between the Canthileptes 

 and the SiluridcB is perhaps stronger than that of any 

 two groups in the whole table : both are the only fa- 

 milies where the head and cheeks are covered with bony 



