Annual, trailing undershrubs; branches 4-angled straggling with densely soft, woolly, deflexed hairs or tomentose; leaves opposite, ovate or slightly orbicular, obtuse at apex, rounded at base, crenate, velvety, silky above or often almost glabrescent below; petiole short; flowers in distant, axillary whorls; bracts minute, linear, densely villous; calyx subsessile, tubular, 10 nerved, straight, subsessile, silky, villous outside, finely pubescent inside in upper half, teeth minute; corolla white, bilabiate, upper lip short, erect, hooded, entire, rarely emarginate, hirsute outside, lower lip longer, spreading, 3-lobed, middle lobe largest, tube straight; disc annular; stamens-4, didynamous included in the upper lip of corolla, filaments glabrous, anthers 2-celled, connivent; ovary 4-partite; style subulate at the apex, the posterior lobe obsolete; nutlets 4, ovoid, triangular, obtuse, dry, basal scar small.