THE GREENL1NGS 



Family LXVIII. Hexagrammida 



BODY elongate, covered with small ctenoid or cycloid scales; 

 head conical, scaly, the cranium without spinous ridges above; 

 preopercle more or less armed, sometimes with entire edges; 

 third suborbital developed as a bony stay articulating with the 

 preopercle; mouth large, with acute teeth in jaws, and usually 

 on vomer and palatines; nostril single on each side, the posterior 

 opening reduced to a minute pore; pseudobranchiae well developed; 

 dorsal fin continuous or divided, the anterior half of many slender 

 spines; anal fin long, with or without spines; lateral line present, 

 sometimes several series of pores developed. 



Carnivorous fishes, mostly of large size, living in kelp and 

 about rocks in the North Pacific; some of them highly valued 

 as food. 



Of the 5 genera found in American waters, only 3 contain 

 food-fishes of any importance. 



The most interesting species of the family is the Atka mack- 

 erel, or Atka-fish, Pleurogrammus monopterygius. 



This interesting fish is the most important species of the 

 family. It occurs in the North Pacific, chiefly among the Aleu- 

 tian Islands. It is not common about Unalaska or the Pribilofs, 

 but about Atka and Attu it is abundant. It is somewhat erratic 



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