Acacia phlebophylla F. Muell. of the family Leguminosae, subfamily Mimosoideae, has not previously been examined for the presence of alkaloids. The species is unique as it is found only in a narrow range of altitude on Mount Buffalo, Vic. The leaves yielded about 0.3% of NbNb-dimethyltryptamine. Thin-layer chromatography of crude extract indicated that this was the only base present. Nb-methyltryptamine and N,N,-dimethyltryptamine have been found in Acacia maidenii, as well as in other genera of Leguminosae (Mimosa, Piptadenia, and Lespedeza), in the Apocynaceae (Prestonia), in the Chenopodiaceae (Anthrophytum and Qirgensohnia) and in the Gramineae (Phalaris).