an annual herb, erect, ascending or decumbent, slender, glabrous, simple or sparingly branched from the base, 4 1/2–12 in. high; stem and branches tetragonous, smooth, nearly bare of leaves above the middle; leaves opposite, ovate or subrotund, obtuse or subacute at the apex, often somewhat cordate at the base, entire or mostly denticulate, membranous, 1/3– 2/3 in. long, 1/4– 3/5 in. broad, petiolate; lower petioles about as long as the leaves; racemes terminal, elongated, many-flowered, 2–6 in. long; pedicels slender, alternate, spreading, 1/4– 3/5 in. long, mostly bracteate at the base; bracts cordiform-lanceolate, sessile, very small or ranging up to 1/5 in. long; calyx-segments lanceolate or ovate-oblong, subacute, 1/12– 1/10 in. long, not ciliate; corolla shortly bisaccate, nodding, 1/8– 1/6 in. broad; filaments 4, subulate, glabrous; capsule narrowly ovoid-oblong, obtuse, about 1/4 in. long. null
