1864: Bulletin 4.7, United States National Museum. 



a. Dorsal fins contiguous or connected. 



b. Anal fin very long, its rays 20 or more. 

 c. Anal fin without spines. 

 HEXAGRAMMINJE : 

 d. Gill membranes broadly united; mouth moderate, the jaws with an outer 



series of stronger teeth, but no canines. 

 e. Lateral lines * 4 or more on each side. 



/. Dorsal fin continuous, or slightly emarginate. 



PLEUROGRAMMUS, 698. 



ff. Dorsal fin with the spines separated from the soft rays by a deep 

 notch. HEXAGBAMMOS, 699. 



OPHIODONTIN^E : 



dd. Gill membranes not connected ; mouth large, the jaws armed with strong 

 canines ; lateral line single on each side ; scales cycloid ; preopercle 

 armed. OPHIODON, 700. 



cc. Anal fin with 3 stout spines. 

 ZANIOLEPIDIN^E : 



g. Gill membranes scarcely united ; spinous dorsal greatly elevated in front ; 

 scales very rough. ZANIOLEPIS, 701. 



OXYLEBIINJE : 



gg. Gill membranes broadly united; dorsal spines low, stiff; head pointed. 



OXYLEBIUS, 702. 



698. PLEUROGRAMMUS, Gill. 

 (ATKA FISHES.) 



Pleurogrammus, GILL, Proc. Ac. Nat. Sci. Phila. 1861, 166 (monopterygius). 



This genus differs from Hexagrammos mainly in the character of the 

 dorsal fins, the high spines being continuous with the soft rays. Scales 

 ctenoid. Lateral lines 5 on each side. The single species known is highly 

 valued as a food-fish, its flesh being rich and tender. (rtXevpor, side; 

 ypawrj, line.) 



2267. PLEUKOGRAMMUS MONOPTERYGIUS (Pallas). 



(ATKA-FISH.) t 



Head 4 in length of body ; depth 4; D. XXI, 25; A. 24; lateral line 210, 

 pores 143; eye 5 in head; maxillary 2f ; snout 3|; interorbital 3; highest 

 dorsal spine If ; highest anal ray 2$ ; pectorals 1J ; ventrals If ; caudal lobe 

 li; gill rakers 6 + 22. Body rather stout, little compressed; head not 

 large, the profile rather steep ; mouth moderate, below the axis ; maxillary 

 extending to below anterior edge of pupil; jaws subequal,the teeth cardi- 

 form, in rather broad bands on front of jaws, the outer series slightly 

 enlarged, a single row on sides ; teeth on vomer and a few asperites on 

 palatines; interorbital wide and evenly convex. Scales small, ctenoid; 

 top of head to just in front of nostrils scaled; cheeks and opercles with 

 scales ; tip of snout, preorbital, suborbital stay, maxillaries, mandible, and 

 a space around edge of preopercle naked ; scales running up the base of 



* Lateral line single in the Japanese genus, Agrammus. 



t Commercially known as "Atka mackerel," It is, however, not a mackerel, nor has it 

 any resemblance to one. 



