Stems firm, slender, wide-climbing, 10–12 ft. long, densely clothed with decurved brown silky hairs. Stipules lanceolate, scarious, striated, persistent, 3–4 lines long. Petioles densely brown-silky, 1 1/2–2 in. long; leaflets three, stipellate, ovate-oblong, the terminal one 1 1/2–2 in. long, 1–1 1/4 in. broad, the apex rounded and mucronate; petiolule 1/4 in. long; lateral leaflets unequal-sided, papyraceous, upper surface green, thinly silky, lower grey and more silky, the main veins raised and subferruginous. Flowers 6–8 in lax long-stalked racemes equalling the leaves. Bracts lanceolate, scarious, persistent. Pedicel 1 line long, silky. Calyx obconic, 2 1/2 lines deep, thinly silky, the upper tooth deltoid acuminate, the others lanceolate or linear reaching a third down. Corolla purplish, twice the calyx. Pod stipitate, an inch long, 1/4 in. broad, narrowed at the base, firm, finely silky, 3–4-seeded.