Abstract: The Chinese medicinal herb, Bao Gong Teng has been identified as Erycibe obtusifolia Benth. Its aqueous extract causes astrong myosis in rabbits. Two constituents have been isolated from the stem of Bao Gong Teng by column chromatographic method and are provisionally named as Bao Gong Teng A and B respectively.Bao Gong Teng A, a colorless viscous liquid, is the new effective constituent for pupillary constriction. Two stable crystalline salts, benzoate and 3,5-dinitrobenzoate were prepared and the former is being used in a pilot study for treatment of glaucoma instead of pilocarpine.Chemical and spectral data reveal that Bao Gong Teng A, C₉H₁₅O₃N, may be a secondary amine. An alcoholic hydroxyl group, an acetate group and a pyrroline structure may also exist in the molecule.