STUDIES ON SHELL FORMATION. X. A STUDY OF THE PROTEINS OF THE EXTRAPALLIAL FLUID IN SOME MOLLUSCAN SPECIES,

Abstract

1. Distribution of the protein fractions of the extrapallial fluid of fourteen species of molluscs was determined by means of paper and cellulose acetate electrophoresis. 2. The extrapallial fluid of species in which the calcium carbonate of the shell occurred as calcite contained a single protein fraction. In those species in which the shell calcium carbonate occurred as aragonite or as both aragonite and calcite, three or more protein fractions were present in the extrapallial fluid.