The haddock (Melanogrammus æglifinus) closely resembles the cod and is of similar quality as food. It is known at sight by the black lateral line. It is found on both shores of the Atlantic and when smoked is the "finnan haddie" of commerce.
The pollack, coalfish, or green cod (Pollachius carbonarius) is also common on both shores of the north Atlantic. It is darker than the cod and more lustrous, and the lower jaw is longer, with a smaller barbel at tip. It is especially excellent when fresh.
Fig. 488.—Pollock, Theragra chalcogramma (Pallas). Shumagin I., Alaska.
The whiting (Merlangus merlangus) is a pollack-like fish common on the British coasts, but not reaching the American shores. It is found in large schools in sandy bays. The Alaska pollack (Theragra chalcogramma) is a large fish with projecting lower jaw, widely diffused in the north Pacific and useful as a food-fish to the Aleutian peoples. It furnishes a large part of the food of the fur-seal (Callorhinus alascanus and C. ursinus) during its migrations. The fur-seal rarely catches the true codfish, which swims near the bottom. The wall-eyed pollack (Theragra fucensis) is found about Puget Sound. Smaller codfishes of this type are the wachna cod (Eleginus navaga) of Siberia and the Arctic codling (Boreogadus saida), both common about Kamchatka, the latter crossing to Greenland.
Several dwarf codfishes having, like the true cod, three dorsal fins and a barbel at the chin are also recorded. Among these are the tomcod, or frostfish, of the Atlantic (Microgadus tomcod), the California tomcod (Microgadus proximus), and Micromesistius poutassou of the Mediterranean. These little cods are valued as pan fishes, but the flesh is soft and without much flavor.
Fig. 489.—Tomcod, Microgadus tomcod (Walbaum). Wood's Hole, Mass.
Other cod-like fishes have but two dorsals and one anal fin. Many of these occur in deep water. Among those living near shore, and therefore having economic value, we may mention a few of the more prominent. The codlings (Urophycis) are represented by numerous species on both shores of the Atlantic. Urophycis blennoides is common in the Mediterranean. Urophycis regius, on our South Atlantic coast, is said to exhibit electric powers in life, a statement that needs verification. In the Gulf of Mexico Urophycis floridanus is common. Farther north are the more important species Urophycis tenuis, called the white hake, and Urophycis chuss, the squirrel-hake. The ling (Molva molva) is found in deep water about the North Sea.
A related genus, Lota, the burbot, called also ling and, in America, the lawyer, is found in fresh waters. This genus contains the only fresh-water members of the group of Anacanthini.