[Illustration: FIG. 377.—Skilfish, _Anoplopoma fimbria_ (Pallas). California. ] =The Skilfishes: Anoplopomidæ.=—The small family of skilfishes or _Anoplopomidæ_ consists of two species found on the coast of California and northward. These resemble the _Scorpænidæ_, having the usual form of nostrils, and the suborbital stay well developed. The skull is, however, free from spines, the scales are small and close-set, and the sleek, dark-colored body has suggested resemblance to the mackerel or hake. _Anoplopoma fimbria_, known as skilfish, beshow, or coalfish, is rather common from Unalaska to Monterey, reaching a length of two feet or more. In the north it becomes very fat and is much valued as food. About San Francisco it is dry and tasteless. =The Greenlings: Hexagrammidæ.=—The curious family of greenlings, _Hexagrammidæ_, is confined to the two shores of the North Pacific. The species vary much in form, but agree in the unarmed cranium and in the presence of but a single nostril on each side, the posterior opening being reduced to a minute pore. The vertebræ are numerous, the scales small, and the coloration often brilliant. The species are carnivorous and usually valued as food. They live in the kelp and about rocks in California and Japan and along the shores of Siberia and Alaska. The atka-fish (_Pleurogrammus monopterygius_) is one of the finest of food-fishes. This species reaches a length of eighteen inches. It is yellow in color, banded with black, and the flesh is white and tender, somewhat like that of the Lake whitefish (_Coregonus clupeiformis_), and is especially fine when salted. This fish is found about the Aleutian Islands, especially the island of Atka, from which it takes its name. It is commercially known as Atka mackerel. [Illustration: FIG. 378.—Atka-fish, _Pleurogrammus monopterygius_ (Pallas). Atka Island. ] In this genus there are numerous lateral lines, and the dorsal fin is continuous. In _Hexagrammos_, the principal genus of the family, the dorsal is divided into two fins, and there are about five lateral lines on each side. _Hexagrammos decagrammus_ is common on the coast of California, where it is known by the incorrect name of rock-trout. It is a well-known food-fish, reaching a length of eighteen inches. The sexes are quite unlike in color, the males anteriorly with blue spots, the females speckled with red or brown. [Illustration: FIG. 379.—Greenling, _Hexagrammos decagrammus_ (Pallas). Sitka. ] [Illustration: FIG. 380.—Cultus Cod, _Ophiodon elongatus_ (Girard). Sitka, Alaska. ]