Page:Natural History, Fishes.djvu/283

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The species, about twenty in number, which compose this Family, are all included in a single genus. They are at once distinguished by a lengthened oval disk running along the top of the head, divided into two longitudinal portions by a central ridge. Across each division run many transverse plates of cartilage, having a finely toothed edge directed backwards. They either lie flat, or can be made by muscular effort to stand partially erect. The body is lengthened, and covered with small scales, ordinarily concealed by a dense coat of mucus, only perceptible to the touch if the hand be passed along the surface from the tail forwards. The mouth is wide, and opens vertically upwards; the jaws, tongue, and vomer are furnished with small teeth. There is a single dorsal placed far back, and opposite to the anal.

The species are chiefly natives of the warmer seas; two are recognised as inhabiting the Mediterranean, and a single example of one of these has been taken on the British coast.

As the technical characters of this, the only genus of the Family, have been enumerated above, they need not be repeated. We shall, therefore, content ourselves with a brief notice of the common Remora (Echeneïs remora, .) of the