Barnacle, a name commonly given both to the pedunculated and sessile cirripeds. By the older naturalists they were classed with the testaceous mollusca, the pedunculated forming the genus lepas, and the sessile the genus hala-nus; they are now recognized as belonging to the articulata. Those provided with the fleshy peduncle or footstalk, as well as those without it, are found firmly fixed below the level of the water to the surface of rocks, shells, and floating substances. Adhering to the bottoms of vessels, they are carried to almost all parts of the world and are found in all seas, even the
Goose Barnacles on a bottle.
Arctic ocean. In warm climates particularly the barnacles attach themselves in such numbers to the bottom of vessels, especially of those not protected by copper, as often to retard their progress. Their bodies are enclosed in shells, white or of a purplish blue color; the peduncle is a fleshy worm-like stem, the extremity of which is fixed to the object upon which the animal is stationed. The food of the barnacles consists of small Crustacea and mol-lusks; these are entangled by the many-jointed cirri which are perpetually thrown out and folded again, so as to serve the purpose of casting a net, which drags the prey to the mouth. The young are produced from eggs, which are discharged by the female in great numbers. On emerging from the egg they are quite free, possessing locomotive organs, and being furnished also with large lateral eyes. In due time a metamorphosis takes place, and, assuming the shapes and habits of their parents, they affix themselves to their future permanent place of residence. It would appear that the growth of these animals is very rapid, for a ship perfectly free of them will return after a short voyage covered with them below the water line.
The flesh of some of the varieties of the barnacle was esteemed by the ancients, and at the present day the Chinese eat it. Except as to the obstruction of vessels, they seem to be perfectly harmless. - The barnacle was in ancient times supposed to produce the bird known as the barnacle goose. (See Goose.) It is from this fabulous connection with the goose that the generic name anatifa of Lamarck (Lat. anas, duck) is still retained for the true barnacles, those furnished with the footstalk; and so of the name anserifera or goose barnacle of Linneeus applied to one of the species of this genus, which is called lepas. (See Cirripedes).