A time series of aerosol concentration profiles for the lower stratosphere was obtained at 34¿ S. (Mildura, Australia) during the 12 months after the eruption of Feugo volcano in Guatemala in October 1974. A persistent thin aerosol-rich layer was found at or near 17 km; it existed from late 1974 and was replenished in the southern winter of 1975. The available evidence indicates that the initial layer was probably not due to the Fuego eruption.