Erect, annual, much branched herb; stem 4-grooved, scaberulous, often spotted with purple; leaves opposite or alternate, upper most simple, other 3-4 cm long, pinnatisect, segments narrow, often laciniate or filiform, distant, often very divided; flowers subsessile, axillary, solitary or in few-flowered racemes; bract short; bracteoles about 1 cm. long, filiform; pedicels slender; sepals 10-nerved, teeth longer than tube, linear- subulate; corolla white, light purple or rose, subcampanulate, up to 3.8 cm long, tube short, throat broad, limbs, spreading; stamens-4, didynamous, anthers of upper or both pairs connivent in pairs; one lobe of each perfect, ovoid, others small, empty, stipitate; ovary 2-celled, stigma thick, tongue shaped obtuse; capsule ovoid or oblong, as long as the calyx, rounded at the tip; seeds many, oblong, striated.