ELECTRIC FISHES, several quite un related fishes which possess the extraordinary property of communicating an electric shock to animals with which they come in contact. The organs which are the source of this power have been much studied by both anatomists and physiologists. They are in all cases—with the possible exception of Malapterusus — formed by the modification of muscular tissue, and consist of a mass of numerous closely packed prisms, each divided into a series of compartments filled with a gelatinous substance. One surface of the fibrous discs thus formed receives a rich nerve supply and is electrically negative, the opposite surface being positive. The entire organ may therefore be likened to a group of voltaic piles. Among the Easmobranchii (q.v.), many of the skates possess rudimentary electric organs, .which reach a high degree of development in the torpedo and an allied genus (Hypnos). In these two genera the
organs occupy a large area on each side of the head and the prisms are arranged ver tically and are supplied by large nerves, four pairs of which arise from a special electrical lobe of the hinder part of the brain, while a fifth is a branch of the trigeminal. In the elec trical catfish (Marapterusus electricus) of the Nile, and some allied species, the entire body is enveloped by an electric layer beneath the skin and the muscles. In the electric eel (q.v.) and all other electrical fishes the organ is placed by the side of the tail and the prisms are dis posed longitudinally. Not alone in structure but in the phenomena of rest and activity these or gans bear a striking resemblance to muscles, which also normally exhibit weak electrical currents.