Twining; glabrous, annual herb, stem angular; petioles striate, stipules linear, lanceolate; leaves 3- foliolate; leaflets very variable, ovate, rhomboidal or lanceolate, acute or obtuse at apex, usually glabrous or sparsely pubescent on both surfaces, margin entire or slightly lobed; flowers in long peduncled condensed racemes; bracts ovate, acute, deciduous, bracteoles lanceolate; calyx glabrous, lobes shorter than tube; corolla white or liliac, standard yellowish outside, bluish-violet inside; stamens diadelphous; anther uniform, filaments slender; ovary sessile or subsessile, hairy; style slender, bearded towards tip, incurved; stigma capitate, oblique; pods long, linear, torulose, glabrous or faintly pubescent; seeds ovoid or rounded, oblong, white.