The functional morphology of the rock-boring lamellibranchPetricola pholadiformisLamarck

Abstract

Living specimens of Petricola pholadiformis Lamarck were obtained from Burnham-on-Crouch, Essex.Studies of the principal organ systems were made on the living animal, particular attention being paid to the ciliary feeding and cleansing mechanisms in the mantle cavity, and the ciliary sorting mechanisms within the stomach. The action of the bulbus on the posterior aorta was also studied.A detailed comparison was made between P. pholadiformis and all the British species of Pholadidae. Thirty anatomical features were found in which P. pholadiformis differed from all of the Pholadidae, and fourteen features in which P. pholadiformis resembled one or more species of Pholadidae. It was concluded that these resemblances were purely fortuitous.