Scatological Studies of the Bivalvia (Mollusca)

The earliest detailed description of faecal pellets in any species of the Bivalvia was given by Dodgson for Mytilus edulis L. and the accepted term, “pseudo-faeces” originated with him. The faecal pellets of bivalves were easily collected by keeping freshly caught animals in glass vessels containing clean water for a few hours. The first shed pellets were picked out as typical. Each animal was usually kept in a separate vessel to prevent confusion of samples and to ascertain the effect of possible individual variation. Careful handling makes it possible to extract nearly complete pellets from the rectum of the dead and preserved animals with the aid of a needle under a dissecting binocular. For the transport of very delicate pellets, such as those of Mytilus, they should be set in gelatine.