Erect herb, up to 1 m, ± woody at the base. Branches pubescent when young. Leaves thin or thick membranaceous, very variable in size and shape; small ones ovate or elliptic, 1.2-3 by 0.8-1.5 cm, acute, base rounded or cuneate; larger ones lanceolate-ovate, often unequilateral, 5-7 by 2-3 cm, acuminate, at base acute; petiole 0.5-3 cm. Flowers usually 4-8 in axillary verticillasters. Pedicels 1-2 mm, sericeous. Calyx 5-6 mm long, in fruit 6-8 mm, pilose on the ribs outside; tube not inflated below. Corolla white, 9-10 mm long. Stamens: anterior pair barely exserted. Nutlets 8 by 2 mm, finely puberulent, with a very conspicuous scar on the ventral base.