The skin of Bufo alvarius, a desert toad of Arizona, contains a number of indolealkylamines and their metabolites belonging to the common series of S-hydroxyindolealkylamines and to the unusual series of 5-methoxyindolealkylamines. The most abundant representative of 5-hydroxyindolealkylamines is, as in numerous other toads, bufotenine (up to 3 mg per g dry skin), the most abundant representative of 5-methoxyindolealkylamines, O-methylbufotenine. In parotoid and coxal glands as much as 5-15 per cent of the dry weight is made up by this compound. Natural O-methylbufotenine has been isolated in a pure form and its identity with synthetic O-methylbufotenine definitely established.