96 PISCES. 



abdomen, sometimes suspended to the apparatus of the shoul- 

 der, or are totally wanting. 



We thus arrive at the three orders of the Malacopterygii 

 ABDOMiNALEs, the SuBBRACHiATi and the Apodes, each of 

 which comprizes certain natural families to be described. The 

 first is particularly numerous. 



It is impossible, however, to apply this mode of division to 

 the AcANTHOPTERYGii; and their subdivision in any other 

 way than by that of natural families is a problem that I have 

 hitherto vainly endeavoured to solve. Fortunately many of 

 these families are possessed of characters nearly as exact as 

 those which could be given to true orders. 



It is, besides, impossible to assign to the families of fishes, 

 the same marked gradation that is visible among those of the 

 Mammalia. Thus the Chondropterygians are connected with 

 Serpents on the one hand by the organs of the senses, and 

 some of them even by those of generation ; while the imperfec- 

 tion of the skeleton in others allies them to the Mollusca and 

 Worms. 



As to the Ordinary Fishes, if any one system is found more 

 developed in some than in others, it is not sufficiently pre- 

 eminent, nor does it exercise a sufficient influence over the 

 whole, to compel us to pay any regard to it in a methodical 

 arrangement. 



We will successively treat of these two series, commencing 

 with the most numerous, that of Ordinary Fishes, and placing 

 at its head the order richest in genera and species. 



ORDER I. 

 ACANTHOPTERYGII. 



The Acanthopterygii form the first and by far the most 

 numerous division of Ordinary Fishes. They are recognized 

 by the spines which occupy the place of the first rays of their 

 dorsal, or which alone support the first fin of the back, where 



