CLASS OF FISHES. 



391 



498. The abdominal malacopterygii are distinguished 

 from the preceding by having the rays of the first dorsal fin 

 cartilaginous, articulated towards the extremity, and generally 

 divided into several branches (Fig. 301). This character is 

 common to it with the two remaining groups of osseous 

 fishes, and to distinguish them it is necessary to add, that 

 the ventral fins are situated under the abdomen, behind the 

 pectoral fins, and not attached to the bones of the shoulder. 

 To this order belong the carp, the pike (Fig. 402), the 

 silurus (Fig. 397), the salmon, the herring, the sardine, and 

 the anchovy. 



Fig. 400. Tunny. 



499. The sub-branchiated malacopterygii have the fins 

 formed in the same manner as in the last ; but their abdominal 

 fins are placed under the pectorals. This division comprises 

 the cod (Fig. 398), the whiting, the remora (Fig. 388), and the 

 family of the pleuronectidse, or flat fish, as the plaice (Fig. 404), 

 the turbot (Fig. 389), the sole, &c. 



Fig. 401. 



Fig. 402. Pike. 



500. Finally, the malacopterygii apodes are characterized 

 by the absence of ventral fins, and of spinous rays in the 

 dorsal fin. To this family belong the eels, the gymnotus 

 (Fig. 394), &c. 



501. The cartilaginous fishes, or chondropterygii, have 

 the skeleton cartilaginous, and sometimes almost membranous, 

 never osseous, the calcareous matter hardening its surface 

 being deposited in little grains. There is even a resemblance 

 between it and that of the tadpole. The superior maxil- 



