RIBBON-FISHES(fTrachyplemdaef a family of marine fishes readily recognized by their long, compressed tapelike body, short head, narrow mouth, and feeble dentition. A high dorsal fin occupies the whole length of the back; an anal is absent, and the caudal, if present, deviates in its direction from the longitudinal axis of the body. The pectoral fins are small, the ventrals composed of several rays, or of one long ray only. Ribbon-fishes possess all the characteristics of fishes living at very great depths. They are extremely fragile when found floating on the surface or thrown ashore, and rarely in an uninjured condition; the rays of their fins especially, and the membrane connecting them, are of a very delicate and brittle structure. In young ribbon-fishes some of the fin-rays are prolonged in an extraordinary degree, and sometimes provided with appendages (see fig. 2). The largest of ribbon-fishes are the species of Regalecus (see Oar-Fish), of which specimens some 20 feet long by 12 inches in depth of body and 2 inches in thickness have been found. Like all deep sea fishes they occur in all seas. The most common of the British seas is the Vagmaer or Deal-Fish lfΓrachypterus arcticus) from 3 to 5 feet long, of which almost every year after the equinoctial gales specimens are picked up on the coasts of North Britain, of the Orkneys, Scandinavia, and Iceland (see also Ichthyology, vol. xii. pp. 684, 691).