LINNEZAN SYSTEM. — FISH. 155 
Scizna. 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- 
{ \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. 
7 
' IV. Aspominat Fisurs. Ventral fins behind the pectoral. 
Cobites. Loach. Body hardly decreasing towards the tail. , 
Amia. Head naked, bony, rough. 
Silurus. Cat-fish. First ray of the dorsal or pectoral fins 
tootaed. 
Teuthis. Head truncate on the fore part. 
Loricaria. Body mailed with a bony coat. 
Salmo. Salmon. Hindermost dorsal fin fleshy. 
Fistularia. Snout cylindrical, witha 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. 
Exocetus. 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 Systema Nature 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 finsnone; body oval, naked ; 
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. 
