lxvi PRELIMINARY SKETCH OF THE 



six orders, the characters of which are taken 

 from the situation of the belly fins . 



Order I. — Apodes ; have no ventral fins. This 

 order embraces the Eel-kind, Torpedo, Sec, 



Order II. — Jugulares. Ventral fins placed 

 before the pectoral ; Cod, Blenny, #c. 



Order III. — Thoracici. Ventral fins under the 

 pectoral; Sucking-fish, Goby, Doree, Plaise, $c. 



Order IV. — Abdominales. Ventral fins placed 

 behind the pectoral ; Skeat, Salmon, Pike, #0 



Order V. — Branchiostegi. Gills destitute of 

 long rays ; Sun-fish, Pipe-fish, fyc. 



Order VI. — Chondropterygii. Cartilaginous 

 gills ; Lamprey, Ray, Shark, #c. 



The two last composed the order Nantes in 

 the class Amphibia in the first editions of Lin- 

 naeus, but have been returned to their proper 

 place by his successors. 



The generic characters of this class are taken 

 from peculiarities in the head, mouth, teeth, 

 nostrils, rays in the membrane of the gills, eyes, 

 general figure of the body, tail, situation of 

 spiracula, Sfc, 



The specific characters are also taken from 

 peculiarities in the above-mentioned parts, but 

 are much too various to enumerate. In the last 



