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"The Common Barnacle, <em>Lepas anatifera</em>, perhaps the best-known example of the order, generally selects floating objects for this purpose, and frequently covers the bottoms of ships to such an extent as to even impede their progress through the water. It adheres by a flexible stalk, which possesses great contractile power. The shell is usually composed of two triangular pieces on each side, and is closed by another elongated piece on the back." &mdash; Goodrich, 1859

Barnacles

"The Common Barnacle, Lepas anatifera, perhaps the best-known example of the order, generally…