Two new alkaloids have been isolated from Decodon verticillatus by an improved procedure for fractionation of the crude alkaloids. The new alkaloids have been converted to the known alkaloids vertaline and decaline by methylation of a phenolic hydroxyl group in each. Vertaline had been assigned structure II previously on the basis of X-ray data and decaline is assigned structure V on the basis of a series of degradative and spectral studies of both alkaloids. A key degradation was the conversion of VI to X and XI by sodium-ammonia. The new des-O-methyl alkaloids were assigned structures V and V-B (4''-OH, 5''-OCH3) on biogenetic grounds. © 1971, American Chemical Society. All rights reserved.