LINN^AN SYSTEM. FISH. 155 



Sciaena. Sea-perch. Head and gill covers with fixed scales. 



Perca. Perch. Gill covers three-leaved, the upper serrate. 



Gasterosteus. Stickleback. Tail carinate at the sides. 



Scomber. Tunny. Tail carinate at the sides ; several spu- 

 f [rious fins between the dorsal fin and tail. 



Centrogaster. Spine-throat. Tail carinate at the sides ; ven- 

 tral fins connected by a membrane, the first four rays 

 spinous, the other six unarmed. 



Mullus. Mullet. Body and gill covers with large lax scales. 



Trigla. Gurnard. Distinct appendages near the pectoral fins. 



I IV. ABDOMINAL FISHES. Ventral fins behind the pectoral. 



Cobites. Loach. Body hardly decreasing towards the tail. 9 



Amia. Head naked, bony, rough. 



Silurus. Cat-fish. First ray of the dorsal or pectoral fins 



tootned. 



Teuthis. Head truncate on the fore part. 

 Loricaria. Body mailed with a bony coat. 

 Salmo. Salmon. Hindermost dorsal fin fleshy. 

 Fistularia. Snout cylindrical, with a cover at the end. 

 Esox. Pike. Upper jaw much shorter than the lower. 

 Elops. Branchiostegous. Membrane double, the outer less. 

 Argentina. Argentine. Vent near the tail. 

 Atherina. Alherine. Body with a lateral silvery stripe. ' 

 Mugil. Mullet- Lower jaw carinate inwards. 

 Mormyrus. Teeth notched ; scales imbricate. 

 Exoco2tus. Flying fish. Pectoral fins as long as the body. 

 Polynemus. Distinct appendages near the pectoral fins. 

 Clupea. Herring. Belly carinate, serrate. 

 Cyprinus. Carp. Gill membrane three-rayed. 



(208.) The additional genera included in the subse- 

 quent editions of the Sy sterna Natures are the follow- 

 ing: they were chiefly defined by Bloch : 



Gymnothorax. Naked-breast. Ventral and pectoral fins none ; 



body eel-shaped. 

 Leptocephalus. Morris. Ventral and pectoral fins none; 



body thin, much compressed. 

 Sternoptyx. Great-eye. Ventral fins none ; body oval, naked j 



breast folded. 

 Stylephorus. Long-eye. Ventral fins none ; eyes placed on a 



short peduncle. 

 Scarus. Scare. Thoracic. Teeth none ; jaws crenate at the 



edges. 



Lonchius. Thoracic. Caudal fin lanceolate. 

 Trachychthys. (Shaw.) Belly armed with large carinate scales. 



