An electrophoretic survey of anthocyanins in flowers of 81 species belonging to 27 plant families indicated that malonated or similarly substituted zwitterionic anthocyanins occur in half the sample. In particular, almost all species surveyed in the Compositae and the Labiatae were positive. The same results were also indicated by HPLC separations. Detailed examination of the anthocyanins of Dahlia variabilis and Plectranthus argentatus confirmed the presence of malonylation through glucose. It appears that anthocyanins substituted by aliphatic dicarboxylic acids may be widespread in the angiosperms.