458 FISHES OF THE FIRTH OF FORTH. 



Division. Page. 



/ Membranes of the anterior part of the dorsal fin 



20. < terminating in loose filaments 21 



' Membranes of the dorsal fin entire 23 



21. 



22. 



Preoperculnm entire 22 



! Preoperculum denticulated Crenilabrus. 259 



f Base of the dorsal fin without spines Labrus, 256 



I Base of the dorsal with a series of forked spines. Zeus. 220 



( Teeth in one row only in each jaw Blennius. 233 



( Teeth in two rows in front of each jaw Murcenoides. 235 



( Ventrals united in the form of a concave disk... Liparis. 383 



( Ventrals separate Zoarces. 237 



c Dorsal fin situated over the anal fin 26 



25. \ 



I Dorsal situated over the ventrals or nearly so.. 31 



i Mouth placed underneath, without teeth Acipenser. 403 



( Mouth placed at the extremity, with teeth 27 



t Three or more spines in front of the dorsal fm. Gasterosteus. 190 

 ' ( No spines in front of the dorsal fin „ 28 



(Caudal fin forked 29 



28 



' I Caudal fin not forked CydopUms. 380 



( Dorsal fin with unlets Scomberesox. 276 



29 < 



( Dorsal fin without finlets 30 



f Length of dorsal fin exceeding twice its height. Belone. 274 



' I Length of the dorsal about equalling its height. Esox. 272 



( Snout with barbules Cobitis. 270 



( Snout without barbules 32 



t Tongue rough with minute teeth Clupea. 315 



( Tongue smooth without teeth 33 



r Central line of the belly very rough 3 strongly 



33. \ serrated Alosa. 329 



' Central line of the belly smooth Leuciscus. 0(fR 



:u. 



Two dorsal fins 35 



Three dorsal fins 55 



