DOGFISH, a name applied to several species of the smaller sharks, and given owing to the habit these fishes have of pursuing or hunting their prey in packs. The small-spotted dog-fish or rough hound (Scyllium canicula) and the large-spotted or nurse hound (Scyllium catulus) are also known as ground-sharks. They keep near the sea bottom, feeding chiefly on the smaller fishes and crustacea. They differ from the majority of sharks in being oviparous. The eggs are enclosed in semi-transparent horny cases, of ten called "mermaids' purses" and these have tendril-like prolongations from each of the four corners, by means of which they are moored to sea-weeds or other fixed objects, until the young dog-fish is ready to make its exit. The larger of these species attains a length of 4 to 5ft., the smaller rarely more than 3o inches. The picked dog-fish (Acanthias vulgaris) is abundant in the temperate seas of both hemispheres, and on both sides of the Atlantic. It attains a length of 4ft., but the usual length is 2 to 3 f t., the female, as in most sharks, being larger than the male. The body is round and tapering, and the mouth is placed ven trally some distance from the end of the snout. There are two dorsal fins, each armed anteriorly with a sharp spine. This spe cies is viviparous, the female producing five to nine young at a birth ; the young when born are 9 to loin. long and similar to the parents, except in size. The picked dog-fish is gregarious, and is abundant at all seasons everywhere on the British coasts. They, even more than other dog-fish, are the special enemies of the fish erman, injuring his nets, removing the hooks from his lines, and spoiling his fish. They are eaten, both fresh and salted, on the west coast of England, and are sold regularly in the French mar kets. Of recent years an attempt has been made to sell them in London under the name of "flake." (See SELACHIANS; FISHES.)