Robust herb with tuberous root; stems glabrous or pubescent, hollow, coarse, twining (rarely prostrate). Leaf-blade ovate in outline, usually deeply pinnately or subpalmately divided into 7–11 lobes, about 11 cm. long and 17 cm. wide, ± cordate, green and glabrous above, pubescent beneath, particularly on the nerves, crenate and bullate between the lateral nerves; lobes linear-oblong, obtuse or subacute, 5.2–8 cm. long, 0.8–2 cm. wide; rarely the lamina is entire, lobed or very coarsely toothed, particularly in cultivated specimens; petiole 4–14 cm. long. Flowers several in a lax cyme; peduncle 2.5–10 cm. long; pedicels 1.5–5.5 cm. long, striate, enlarging in fruit; bracts 6 mm. long. Sepals elliptic, 1.2–1.8 cm. long, 0.8–1.2 cm. wide, pubescent or glabrescent, accrescent in fruit. Corolla-limb red-purple or white, salver-shaped, 7 cm. diameter, with frilly margin; tube narrow, 7.5– 8 cm. long, 0.7 cm. in diameter (Fig. 22/8, p. 102). Capsule ovoid, 2.6 cm. long. Seeds elongate-ovoid, 9–10 mm. long, 7–8 mm. wide, densely covered with white woolly hairs up to 2 cm. long.
