The Crystalline Style of the Mollusca and a Carnivorous Habit cannot Normally Co-exist

Abstract

THE crystalline style of the Lamellibranchs and many Gastropods consists of a gelatinous rod formed of protein of a globulin type. It would, therefore, be readily digested by any extracellular proteoclastic enzyme in the alimentary tract. Since the development of the carnivorous habit demands (with such rare exceptions as the one noted below) the presence of an enzyme capable of breaking down the flesh of the prey into soluble polypeptides and amino acids (for example, in Cœlenterates, Decapod Crustacea, and Cephalopods), it follows that a mollusc cannot normally both possess a style and be a carnivore.