A robust annual reaching 3 ft. high, with copious firm flexuose branches densely clothed with spreading grey or ferruginous silky pubescence. Stipules linear-subulate, 1/4– 1/2 in. long. Leaves nearly sessile, rachis 4–5 in. long; leaflets in 6–9 pairs, linear or oblanceolate, 1/4– 3/4 in. broad, truncate or emarginate with a mucro, upper surface glabrous, lower densely clothed with grey silky pubescence, midrib ferruginous. Flowers in lax terminal racemes sometimes a foot long, usually sessile, sometimes with flowers from the axils of the leaves. Bracts linear, 1/4 in. long. Pedicel equalling the calyx, which is densely ferruginous-silky, 2 lines deep, campanulate, the lower tooth lanceolate, about equalling the tube, the others deltoid, shorter. Corolla reddish, 1/2 in. deep, the standard 4 lines broad, densely brown-silky on the back. Pod linear-oblong, 1 1/2–2 in. long, rather over 1/4 in. broad, thinly brown-silky, 7–8-seeded. Style bearded along the upper side.