Eel

Eel, a book-neune for any fish of the Physostomous family Murtenidre, dating from the Chalk, and containing 26 genera with 230 species, widely distributed in temperate and tropical rivers and seas, some being deep-sea forms, euid all frequenting the bottom. The body is much elongatecl, and naked or covered with rudimentary scales. There are no ventral fins, and when vertical fins are present they are continued above and below, or the continuity is broken only by the tip of the tail. The teeth are well developed, and all the species prey on other fish. [Conger, Electrical Fishes, Murjena.] The name, however, is principally used for the genus Anguilla, of which two species (A. anguilla, the Common, and A. latirostris, the Brood-nosed Eel, Grig, or Glut) are British. In this genus, which has about 25 species, from temperate and tropical rivers and coasts, minute scales are embedded in the skin, the teeth are small, and the unpaired fin is continuous. The mode of reproduction is unknown, and microscopic examination is necessary to distinguish the sexes of individuals taken from fresh water. They spawn in brackish water, or in the sea, for during the summer shoals of young eels are met with ascending rivers, passing over floodgates, and sometimes making their way across marshy ground or wet grass. Old fish, also, often leave the water by night in search of food, and they pass the winter in a torpid condition in mud. They feed principally by night on aquatic animals, spawn, and carrion. The Common Eel, the best-known species, is about 3 feet long, greenish-brown above, and whitish on the belly. It is valued as a food-fish, and on many rivers eel-fishing is an important industry.