Barnacles XXL made on iron standard.

Barnacles (Sessilia) as the common barnacle (Semibalanus balanoides) are an order of crustaceans. They seem at first sight for crabs or shrimp, but are assigned to the branch leg lobsters (Cirripedia). They attach themselves to different surfaces: wood, on rocks, shells and even on the skin of whales and shield of sea turtles. The housing is often white and rock hard. The shape may be conical but in dense populations, they can grow into tall columns. They consist of a cabin of six lime platelets, with a lid that is formed of two plates lime. The larvae of barnacles have no shell and swim freely. Some barnacles live fully embedded in their host, as in the inner edge of the shell of the (Buccinum undatum), especially when it is occupied by his secondary occupant: the common hermit crab (Pagurus bernhardus).

 
Barnacles