Erect or ascending, perennial herb; stems sparsely to moderately hairy in upper part, ± glabrous below. Lvs sparsely to densely hairy on petiole and undersurface of leaflets, ± glabrous above; petioles c. 4-20-(35) mm long; leaflets narrowly elliptic to obovate, usually obtuse, sometimes acute or emarginate, mucronate, obtuse to cuneate at base, irregularly serrate near apex, uniform in colour, c. 6-25-(35) mm long; terminal petiolule 2-6 mm long; lateral petiolules up to 1 mm long; stipules ovate to lanceolate, acuminate, entire or irregularly serrate. Infl. with 10-numerous fls; peduncles moderately hairy, > petioles; pedicel <, ± =, or > calyx tube. Calyx ± glabrous or hairy; calyx teeth triangular, acuminate, <, ± =, or > tube. Corolla usually purple or bluish, rarely pale blue or almost white, 7-12 mm long. Pod moderately hairy or ± glabrous, coiled in 11/2-3 turns with a hole through the centre, reticulately veined but otherwise smooth, 4-6 mm diam., 10-20-seeded; seeds yellow to brown, c. 3 mm long.