A vigorous glabrous climber, attaining at least 25 ft in cultivation, climbing by means of tendrils which are borne singly in the leaf-axils. Young stems slender, green, ribbed. Leaves deeply three-lobed with the lateral lobes spreading almost at right-angles to the terminal, the whole blade 11⁄4 to 2 in. long and 15⁄8 to 3 in. wide; lobes oblong, rounded and shortly mucronate at the apex, entire except for a small mucronate tooth on each side, terminal lobe 5⁄8 to 11⁄4 in. long, 7⁄16 to 7⁄8 in. wide, the laterals a little shorter and narrower, upper surface deep bright green, lower surface paler; petioles 5⁄8 to 11⁄4 in. long; stipules leafy, broadly ovate to roundish, up to 1⁄2 in. long, undulately and widely toothed. Flowers on stout pedicels 21⁄4 to 31⁄4 in. long; bracteoles rich mauve-purple, borne close to the perianth, broadly cordate and up to 3⁄4 in. long. Perianth rich mauve-purple or amethyst, 2 to 21⁄2 in. long, with a broad tube swollen to 3⁄4 in. wide at the base; sepals and petals oblong-lanceolate, tapered to a narrow, acute apex, 3⁄4 to 13⁄8 in. long, and about 1⁄4 in. wide at the base; corona of numerous filaments about 3⁄16 in. long arising near the mouth of the perianth-tube and standing erect above it. Androgynophore 13⁄8 in. long; stamens with filaments up to 3⁄8 in. long. Ovary ellipsoid, about 1⁄4 in. long; styles three, diverging a little, 1⁄4 in. or slightly more long; stigma globose.
Native of central Bolivia and adjacent Paraguay to N. Argentina, at 8,000 to 9,500 ft. The above description is made from a plant that once grew in the Temperate House at Kew, raised from seeds received in 1954 from the late Norman Hadden, which had been collected in Bolivia by Miss W. M. A. Brooke. All the plants now growing in Britain are believed to be of this origin. The hardiness of this species is not yet fully tested, but it survived the very hard winters of 1961-3 at Porlock in Somerset, and grows vigorously there.