Erect, much branched, spreading, hispid herb; stem 4-angled, swollen at nodes, leaves petiolate, opposite, ovate, elliptic, slightly rounded at base, acuminate at apex, thinly pubescent on both surfaces, especially on nerves beneath, subentire or crenulate; flowers in di- or trichotomous cymes arranged in lax, divaricate, pubescent, panicles; bracts-2, opposite, unequal, linear, spathulate, acute, mucronate, margins membranous; bracteoles 2, subequal, linear-lanceolate, almost similar to but shorter than bracts; calyx deeply 5-lobed, sepals equal, linear-lanceolate with ciliate margins; corolla rose pink or purple, tube slender, limbs deeply 2-lipped, upper lip subentire, obtuse, lower very shortly 3-lobed; stamens 4, all perfect, didynamous, filaments connate near the base, anthers 2-celled, cells linear, muticous; ovary 2-locular, 4-ovuled, style filiform, stigma minutely bifid; capsule stalked, oblong or ellipsoid, acuminate, pubescent; seeds-4, ovoid, compressed, glabrous.