CLASS V. PISCES. 



(I. O S S E I.) 



Skeleton bony ; the osseous matter disposed in fibres : 

 sutures of the cranium distinct: maxillary and 

 intermaxillary bones, always one, and generally 

 both, present. 



i. PECTINIBRANCHII. Bronchia in con- 

 tinuous pectinated ridges; furnished with an 

 opercle and branchiostegous membrane: jaws 

 complete, and free. 



ORDER I. ACANTHOPTERYGII. 



The first portion of the dorsal fin, or the entire first 

 dorsal when two are present, with simple spinous 

 rays : also the anal and ventrals with one or more 

 of the anterior rays generally spinous. 



I. PERCID^E. Scales generally rough, with 

 ciliated margins : margin of the opercle or pre- 

 opercle, sometimes both, denticulated, or armed 

 with spines: both jaws, as well as the vomer, 

 and almost always the palatine bones also, armed 

 with teeth. 



