Image of Pacific Acorn Barnacle

Description:

This large individual (2.5 to 3 cm long) is unusual in several ways. Most barnacles are roughly as long as wide but this individual is nearly twice as long as wide. Also, there are several young barnacles which have settled on the inside surface of the plates, although the original barnacle is still alive.Photo taken by Dave Cowles, June 2011 in the upper midlittoral at Swirl Rocks between two rock walls.