Small tree, shrub or liane; twigs grey, pubescent when young. Buds inconspicuous. Stipules triangular, fibrous, caducous, 2–5 mm. long and 2 mm. broad; leaf-rhachis khaki pubescent, up to 7 cm. long, including a petiole of up to 2.5 cm., prolonged 3–7 mm. beyond the lateral leaflets; stipellae subulate, 1.5–2 mm. long; petiolules khaki pubescent, 1–1.5 mm. long; leaflets 5 or, more often, 7, elliptic or oblanceolate with a short broad oblanceolate tip, rounded and narrowed at the base, glabrous above, appressed pubescent, sometimes with a golden sheen, beneath; principal nerves 6–7 on each side, not reaching the margin. Inflorescence a khaki pubescent terminal panicle, the side branches each with 2–5 flowers and mostly under 5 mm. long but the lower ones sometimes up to 2 cm.; bracts ovate, up to 3 mm. long, pubescent, caducous; pedicel up to 6 mm. long; bracteoles at calyx-base, ovate, ± 2 mm. long. Calyx velvety, greenish-brown; upper lip longitudinally wrinkled in the bud, resembling the standard in shape, ± 14 mm. long, 8 mm. wide at the base and 22 mm. wide near the tip when mature, notched at the apex, with 8 branching longitudinal veins and a well-marked vein-network between; lower teeth some 8 mm. long and 3 mm. wide near the base, the 2 lateral ones asymmetric; calyx-tube ± 3 mm. long above the insertion of the stamens and 2 mm. below. Corolla mauve, strongly veined, glabrous; blade of standard emarginate, with a callous transverse fold at each side of its base, ± 14 mm. long and 21 mm. wide, the claw broad, tapering, ± 4 mm. long and 3 mm. wide at the base; claws of wings and keel attached to filament-sheath; wings 16 mm. long including a claw of 3 mm., the blade folded at the base, 11 mm. wide near the tip, the auricle 2.5 mm. long; keel 18 mm. long including a claw of 6 mm., pouched at the sides, ± 10 mm. wide, with an auricle of 1.5 mm. Vexillary stamen free, curved and widened at the base, some 12 mm. long; filament-sheath 8–9 mm. long, free parts 7–8 mm. long and curved through 90°; anthers 1.6–1.7 mm. long. Disc (nectary) 1–1.5 mm. long, collar-shaped, 10-lobed at the edge, closely clasping the ovary-base. Ovary 12 mm. long, densely silky pubescent, with 8 ovules at and below the middle; style glabrous, gradually curved through 90°; stigma small, punctate. Immature pods suboblong, the upper margin curved, up to 10 cm. long and 2.3 cm. wide, densely rusty tomentose, paler towards the margin, 4–6-seeded, or fewer by abortion; sutures, especially the upper, slightly thickened; beak short, somewhat down-curved. Immature seeds oblong, flat, obliquely transverse. Fig. 23, p. 121.
