The amino acid signature of fourteen genera of Mollusca, both Bivalvia and Gastropoda, was determined on over 300 individual valves. Examination of eight specific sets of amino acid ratios (for example: aspartic acidlglutamic acid, leucine/valine) indicates that these I4 genera (PatefIa, Litrorina, Nucella, Buccinum, Turritella, Macoma, Scrobicularia, Mytilus. Cerastoderma, Arctica, Glycymeris, Venus, Mya, and Hiatelfa) can be distinguished one from another with a high degree of certainty.Discriminaticin between genera can be based on quantitative assessment of the probability of an individual analysis belonging to a specific genus. We conclude that the amino acid signature is sufficiently distinct that small shell fragments can be assigned to a genus on the basis of the amino acid chromatography. In some instances, for example Lirtorina, it may even be possible to identify fragments to specific species.