More than 90% of the protein of two Pleistocene bone fossils and 30-60% of that of several dinosaurs was solubilized by heating with water at 110 -- . For the Pleistocene and dinosaur gelatins, 70-90 and 60-75% respectively of the amino acids were present as peptides. Most of the fossil proteins not solubilized by water could be rendered soluble by mild treatments with HC1; 60% or less of this was peptide. -- AATA