LEPAS, the ACORN, in zoology, a genus belonging to the order of vermes testacea. The animal is the triton; the shell is multivalve, unequal, fixed by a stem or fessile. There are several species, of which the most remarkable is the anatifera, consisting of five shells depressed, affixed to a pedicle and in clusters. It adheres to the bottom of ships by its pedicles. The tentacula from its animal are feathered; and have given the old English historians and naturalists the idea of a bird. They ascribed the origin of the barnacle goose to those shells. See Plate CLIX. fig. 8.