Badger and Beechaml reported the identification of tetrahydroharman as an alkaloid of Petalostylis labicheoides, a shrub of the family Leguminosae, but they did not identify other bases. We have now examined the alkaloids obtained in 0.4-0.5% yield from a sample of Petalostylis labicheoides var. casseoides Benth, collected near Alice Springs in central Australia, and we find that tryptamine is by far the major component. Three other bases are present in our sample in addition to tryptamine, but in trace amounts only, and of these one is considered on the basis of an examination by thin-layer chromatography and gas chromatography to be NbNb-dimethyltryptamine, while another from similar comparison appears to be tetrahydroharman. Nb-Methyltryptamine could not be detected.A satisfactory comparison of our results with the earlier work of Badger and Beechaml cannot be made because these authors did not specify a yield of either tetrahydroharman or of total bases. Our results suggest however that there may be considerable differences in alkaloid composition between the varieties of P. labicheoides. Tryptamine has been found in a number of leguminous species including Acacia species.