206 PISHES. 



** Dorsal fin single, not divided to its base. 

 k. Fresh water species. 



I. Ventrals I, 5; dorsal spines 8 to 12; vent normal. 



m. Teeth on vomer ; anal spines 3 to 9. ICHTHELID^E, 92. 



mm. No teeth on vomer ; anal with 2 (or 1) spines, the 



second very strong. . . . SCMENID^, 94. 



II. Ventrals 7-rayed; dorsal spines 3; vent jugular. 



APHREDODERnXE, 93. 



Kk. Marine species. 



1. Cheeks mailed (as in Cottidce, etc.) 



n. Body covered with bony, keeled plates ; no dorsal 

 spines. . . . Agonidce, the Sea Poachers. 



nn. Body with ordinary scales ; spinous dorsal many- 

 rayed. . . Scorpcenidce, the Sea Scorpions. 



2. With broad, cutting, incisor -like front teeth, or with 



crushing, molar-like lateral teeth or both ; scales rather 

 large ; usually a recumbent free spine in front of the 

 dorsal fin. 

 o. Opercular bones entire ; vertical fins not much scaly. 



SparidcB) the Sea Breams. 



oo. Preopercle denticulated ; soft parts of vertical fins 

 densely scaly. . Pimelepterid, the Fat-Fins. 



3. Body much compressed and elevated ; the soft rays of the 



vertical fins covered high up with ctenoid scales ; teeth 

 villiform ; body often dark-banded. 

 p. Dorsal with less than 10 spines, separated by a notch 

 from the soft part; spinous dorsal scaleless. 



Epliippidm, the Moon FisJm. 



pp. Dorsal undivided, with 10 or more spines, scaly 

 throughout; fins often filamentous. 



ChcetodontidcB, the Chcetodonts. 



4. Ventrals wanting ; scales minute ; body high, much 



compressed. . Stromateidce, the Harvest Fishes. 



5. Ventrals jugular, few-rayed or wanting; body long and 



low ; dorsal fin very long, occupying most of the back, 

 at least half of it and sometimes all composed of flexible 

 spines ; scales small or none ; usually an anal papilla. 



