Dogfish, any species of Scyllium, the type of a family (Scylliidae) of Cartilaginous 1'ishes from temperate and tropical seas. They are small sharks with two dorsal fins, an anal fin always present, a distinct spiracle, and have no nictitating membrane. The species of the type-genus live near the bottom, feeding on dead fish and on crustaceans, though they are by no means particular in their diet. Two species are British: (1) S. canicula, the Rough Hound, or Lesser Spotted Dogfish, about two feet long, rufous gray, spotted with brown above, and yellowish below; and (2) 8. catulus, the Nurse Hound, or Larger Spotted Dogfish, somewhat like the former, but of larger size, and with larger markings. The eggs are deposited in oblong horny capsules, locally known as mermaids' or sailors' purses, with a long filament at each corner, which moor the egg-case. The flesh of these fish is dry, though it is sometimes eaten. Prist.iurusmelanost.OTna, . the Black-mouthed Dog, is also British. The Spiny Dogfishes belong to the genus Acanthias. A. vulgaris, the "Picked" dogfish, so called from its spinous dorsal fins, common on our coasts, is viviparous. It is detested by fishermen for the damage it does to their nets and lines, and for its ravages among food fishes.