suffruticose, tall, erect, glabrous; branches terete, virgate; petioles filiform, very long, acute, naked, or, in the young plant only, bearing 3–4 pair of obovate-oblong leaflets, the terminal petioled; racemes on long peduncles, erect, laxly several-flowered; flowers pedicellate, bracts subulate, deciduous; petals glabrous, or minutely puberulous; calyx teeth subulate; legumes terete, pedicellate, acute, glabrous, many-seeded. Stems 3–6 feet high, somewhat woody below, half herbaceous above. Branches numerous, very erect, round, laxly set with petioles or phyllodia. These petioles are 3–5 inches long, subulate, somewhat pungent, glabrous, always leafless except in the young plant. Racemes lengthening as the flowers advance, exceeding the petioles. Flowers purple, nearly glabrous. Calyx-teeth variable in length. Legumes 1 1/2–2 inches long, very convex.
