FISHES OF THE GULF OF MAINE 7 



Key D — Continued 



4. Mouth large and strongly oblique; there are no ventral fins Wrymouth, p. 500 



Mouth small and horizontal; with small ventral fins Rock eel, p. 492 



5. There are no ventral fins refer to Eel family key, p. 150 



With small but distinct ventral fins, situated forward of the pectorals 6 



6. The ventrals are situated behind the gill openings and are of ordinary form refer to Eelpout family, key, p. 509 



The ventrals are situated on the chin, well in front of the gill openings and are reduced to forked, barbel-like struc- 

 tures Cusk eel, p. 517 



7. The ventral fins are situated below the points of origin of the pectorals; the skin is conspicuously scaly. 



refer to Grenadier family, key, p. 243 

 The ventral fins are situated far back, behind the tips of the pectorals; the skin is soft, without scales. 



Chimaera, p. 79 



Key E 



Bony fishes of ordinary form, with 2 or 3 well-developed dorsal fins and with the anal fin and the rearmost dorsal 

 separated from the caudal fin. (from No. 23, p. 6). 



1. Three dorsal fins and 2 anal fins .refer to Cod family, key (in part), p. 173 



Only 2 dorsal fins and 1 anal fin 2 



2. With one or more small finlets between the second dorsal and anal fins and the caudal fin 3 



No finlets between the second dorsal and anal fins and the caudal fin 4 



3. With more than 3 dorsal finlets and 3 anal finlets refer to Mackerel family, key, p. 317 



With only 2 dorsal finlets and 2 anal finlets Escolar, p. 349 



With only 1 dorsal finlet and 1 anal finlet Mackerel scad (Pompano family, in part), p. 374 



4. Head very broad; top and sides of head bony, with sharp spines or horns 5 



Head not noticeably broad; sides of head have no spines or horns 7 



5. First (lower) few rays of the pectoral fins are not separate from the remainder of the fin; the mouth is very large 



refer to Sculpin family, key, p. 440 



First (lower) few rays of the pectoral fins are separate from the remainder of the fin; the mouth is not very 



large - 6 



6. Each of the first (lower) 2 or 3 rays of the pectoral fins have the form of a separate feeler; outline of tip of snout is 



concave; the first few spines of the first dorsal fin are not separate from the remainder of the fin. 



refer to Sea robin and Armored sea robin, key, p. 467 

 First (lower) few rays of the pectorals do not have the form of feelers, but are connected, one with the next, by mem- 

 brane, as a separate fin; outline of tip of snout convex; the first few spines of the first dorsal are separate. 



Flying gurnard, p. 472 



7. First spine of first dorsal fin is very much stouter than the other spines, and can be locked erect by the second spine; 



no ventral fins; skin of the sides is very hard Triggerfish, p. 520 



First dorsal spine is not much stouter than the others and cannot be locked erect by the second spine; ventral fins 

 are well-developed; skin of the sides is soft 8 



8. The space between the two dorsal fins is nearly as long as the first dorsal fin, or longer; the ventral fins are situated 



behind the middle of the pectorals -9 



There is little or no free space between the two dorsal fins; the ventrals are in front of the middle of the pectorals... 11 



9. Jaws long; teeth large and strong; anal with one spine Barracuda, p. 306 



Jaws short; teeth weak 10 



10. Anal fin is about as long as head (snout to gill openings) and has one weak spine, refer to Silverside family key, p. 302 

 Anal fin is only about half as long as head and has three stiff spines (only two spines in very young specimens). 



Mullet, p. 305 



11. Caudal peduncle is extremely slender; the caudal fin is deeply forked Pompano family (in part) key, p. 371 



Caudal peduncle is at least moderately deep and thick; the caudal fin is only moderately forked, at most 12 



12. First dorsal fin is much lower than second dorsal 13 



First dorsal fin is as high as the second dorsal fin, or higher 14 



13. Anal fin is nearly as long as second dorsal fin Bluefish, p. 383 



Anal fin is only about one half as long as second dorsal fin Rudderfish (Pompano family in part), p. 373 



14. Body very thin through, flat sided, nearly two-thirds as deep as it is long to base of caudal fin; the back and also the 



ventral edge of the body are armed with bony plates; there is a finlet of three short spines in front of the anal 



fin John Dory, p. 297 



Body stout, not more than one-third as deep as it is long; the sides are rounded; the back and lower surface are 

 not armed with bony plates; there is no finlet in front of the anal fin 15 



