48 LEPIDOSTEUS. GADID^E, OR COD TRIBE. 



creased knowledge of its internal structure, however, and of the 

 fossil species most nearly allied to it (which are very numerous 

 in the older rocks), has led to a very different position being 

 assigned to it. Its skeleton differs in many particulars from 

 that of ordinary Fishes, and presents several points of resemblance 

 to Reptiles ; and this approximation is equally remarkable in 

 the structure of the respiratory apparatus, the air-bladder being 

 double, and communicating with the oesophagus by a regular 

 trachea or wind-pipe, furnished with a glottis at its upper ex- 

 tremity, so as to be nearly as complete as the lungs of the 

 Siren. In regard to the order of Sauroid fishes, of which this is 

 nearly the only genus at present remaining, but which was 

 once the predominant group of Fishes, more will be said 

 hereafter ( 582). The Lepidosteus is an inhabitant of the 

 rivers and lakes of America, most of the species being restricted 

 to its warmer parts. 



ORDER III. MALACOPTERYGII SUB-BRACHIATI. 



573. The Fishes of this order, from the position of their fins, 

 have greater facility of ascending and descending, than the ab- 

 dominal fishes ; and the range of depth inhabited by the same 

 animal is consequently greater, except where, as in the Flat- 

 fish, there is a peculiar adaptation to a residence at the bottom 

 of the sea. The first family is that of the GADID^E, or the Cod 

 tribe ; which have a long body, rather slender, and covered with 

 soft scales, the head, however, being naked. They live for the 

 most part in the seas of cold or temperate climates ; and from 

 their size and their tendency to congregate in particular localities, 

 as well as from the wholesomeness and good flavour of their flesh, 

 they are probably more important to Man than any other family 

 of Fish. The Cod fishery on the banks of Newfoundland sends 

 a vast supply to almost every part of the world ; and the amount 

 caught on the British shores also is very considerable. The 

 appearance and quality of the fish vary considerably according 

 to the nature of the ground on which it is taken. Its repro- 



