marine shellfish attached firmly to rock in the intertidal zone. When submerged at high tide, little, feathery appendages come out of the opened top. The big barnacles are covered with little barnacles.
tidal zone of the Pacific Ocean open to surf
these big barnacles can be steamed and eaten (traditionally cooked in the hot ashes of a rock-lined pit, covered with a cedar mat and a little water poured on, enough to steam them.