Tendriled liana; stems 6-ribbed, brown-hirtellous especially on ribs. Leaves biternate, mostly to 15 cm long; rachis narrowly winged; leaflets ovate to rhomboid, obtuse to acuminate at apex, attenuate at base, coarsely and obtusely toothed above middle, softly pubescent (especially below and on raised midrib above), the terminal leaflet mostly 5-9.5 cm long, 2.5-6 cm broad, the lateral leaflets smaller. Thyrses in racemes 5-15 cm long and borne in axils and on tendrils, or in terminal racemose panicles; inflorescence branches softly short-pubescent; flowers white, ca 3 mm long; sepals ovate, short-tomentose; petals narrowly obovate, borne atop large greenish glands, spreading broadly at anthesis, the scales of the anterior petals with the margin villous and turned inward, the appendage short, villous, the crest broader than long, bifid, recurved toward outside; staminal cluster spreading, leaning away from axis, otherwise typical; filaments sparsely villous, all +/- recurved at apex; ovary glabrous. Fruits cordate-ovate, 1.7-2.2 cm long, the cells sparsely to densely (when young) villous, the wing +/- glabrous or subvillous, often reddish at maturity. Wetmore & Woodworth 83.