Annuals, 20-60 cm tall, entirely with appressed white hairs. Stems often branched from middle and apically, quadrangular above. Leaves sessile, lanceolate to linear-lanceolate, 1-4.5 X 0.3-1 cm, margin sparsely dentate. Spikes terminal; lower bracts leaflike. Calyx campanulate, 4-7 mm, slightly inflated in fruit; lobes narrowly triangular. Corolla purple, purple-red, or pale red, 8-10 mm, white villous outside. Capsule narrowly oblong, slightly compressed, 4-7 mm, apically hirsute. Seeds ellipsoid, ca. 1.5 mm. Fl. Jul-Aug.