Datura sanguinea R. and P., the Dark‐red Datura, is a perennial species growing as a shrub or small tree in Peru and Ecuador. It has been grown in England and the chief alkaloid present is hyoscine. The structure of the leaves and stem is described and compared with other medicinal species of Datura. The characters by which the dried drug may be recognised and distinguished from stramonium are given. The pollen grains are described as an additional means of differentiation.