Barnacle

Barnacle. The Barnacle is one of the best known of the Cirripedia, and is the type of the family Lepadidae; its generic name is Lepas. The larvae are small free-swimming Crustacea known as Nauplius (q.v.), but during development they; attach themselves by the head to some usually floating body, such as wood or a ship's bottom. The adult consists of a long fleshy peduncle or stalk which bears a body protected by a multivalve shell. There are six pairs of appendages or limbs, which may be protruded through a slit between the pieces of the shell. By the movement of these limbs currents of water are established which bring the barnacle its food. They are all marine.

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