Two kinds of new lectins, CATL-I and CATL-II, were partially purified from the intestine of Chlorostoma argyrostoma turbunatum by physical saline extraction, salt fractionation, ion exchange chromatography and gel filtration. CATL-I and CATL-II were purified 39.4 and 15.8 fold with a yield of 8.8 and 7.4%, respectively. On polyacrylamide gel electrophoresis, CATL-I demonstrated one major and one minor bands. This lectin agglutinated human and other animal erythrocytes nonspecifically and also agglutinated murine splenic lymphocytes. Carbohydrate specificity of the lectins was determined by inhibition of the agglutinability by methyl-${alpha}-_D$-galactopyranoside and $_L-rhamnose$ at a final concentration of 6 mM. The lectins contained relatively high amounts of acidic amino acids, but the contents of sulfur containing amino acids were very low or was not estimated. Immunochemical studies were carried out to identify some properties of marine animal lectins.