There are two distinct types of demersal fish: the “round” and the “flat.” The body of a round fish is more or less circular in cross-section, for example cod, while that of a flat fish is flattened, for example sole, ray. The most important edible demersal fish can be classified as follows— (_a_) The _Gadidae_—related to the cod. Cod—inhabits northern waters, notably the North of Britain, Iceland and Newfoundland. Ling—inhabits northern waters: West of Scotland and Ireland, and North towards Iceland and Newfoundland. Haddock—inhabits northern waters. Nearly half the total catch is obtained in the North Sea, from the White Sea to the Bay of Biscay. Whiting—found in great numbers in the North Sea. It is more coastal than the cod or haddock. Hake—found from Norway to the Mediterranean. The greater part of the catch is obtained off the south-west of Ireland. Hake is also caught off Morocco and in the Bay of Biscay. (_b_) The _Pleuronectidae_—related to the plaice and sole. Sole—a shallow-water fish, common in the Irish Sea, and particularly abundant in southern waters down to Morocco. Plaice—inhabits northern waters—all round Britain and Iceland. Flounder—inhabits estuaries, for example, of the North Sea and the Baltic. Halibut—inhabits northern waters. It attains a large size, six feet or more. [Illustration: FIG. 3 LEMON SOLE (_Pleuronectes microcephalus_) Length up to 16 ins. _Food._—Small crustaceans and worms. _Range._—From North of Europe to the Bay of Biscay.] [Illustration: FIG. 4 SKATE (_Raia batis_) Length up to 7 ft. _Food._—Crustaceans and molluscs, and fish. _Range._—Round the British Isles and along the coast of Western Europe.] Turbot—not very abundant. It inhabits the deeper parts of the North Sea. Brill—inhabits southern waters, and is fairly abundant. (_c_) The _Raüdac_. Skates and rays—found all round Britain, more particularly the Western area of the English channel.