An unusual enzymatic reaction: the direct hydroxylation of tryptamine to 5-hydroxytryptamine (5-HT) has been shown to occur in tissues of Piptadenia peregrina. 5-HT, but not N,N-dimethyltryptamine, was found to be a good precursor of bufotenine and it is suggested that the intermediates in the synthesis of bufotenine from tryptophan in this plant are tryptamine, 5-HT and N-methyl-5-HT. The presence of a number of unidentified indoles in the dormant and germinating seeds is reported.