Northern Rock Barnacle - Semibalanus balanoides
Common, intertidal barnacles that resemble volcanoes or dragon's eyes :P. They have a membranous base and the outer shell consists of white, overlapping, shell-like plates that grow with the animal.
Habitat: Adhered to a snail in the intertidal zone
''Semibalanus balanoides'' is a common and widespread boreo-arctic species of acorn barnacle. It is common on rocks and other substrates in the intertidal zone of north-western Europe and both coasts of North America.