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FISHES OF THE FIRTH OF FORTH AND 

 TRIBUTARIES. 



CLASS PISCES. 



Vertebrated animals with red blood respiring by gills or 

 branchiae, and moving in water by the aid of fins. 



SUB-CLASS L— PISCES OSSEI. 



Bones fibrous ; cranium divided by distinct sutures, 

 branchia3 free, membrane furnished with rays. 



ORDER I ACANTHOPTERYGII. 



First portion of the dorsal-fin, or the entire first dorsal, 

 when two are present, with simple spinous rays ; first ray 

 of the anal fin always spinous, and generally the first ray 

 of the ventrals. 



Family I. PERCID.;E. — Operculum, or preoperculum, 

 denticulated or spiny ; scales generally ciliated ; jaws, front 

 of the vomer, and almost always the palatine Ijones, furnish- 

 ed with teeth. 



Genus PERCA. — Dorsal-fins two ; preoperculum notch- 

 ed below ; operculum ending in a flattened point ; tongue 

 smooth, without teeth. 



