Slender biennial with usually only a few opposite, erect branches beyond the middle, subterete or somewhat angled but scarcely winged; lvs sessile, lanceolate to narrowly oblong or linear, 1.5-4 cm, less than a third as wide, acute, narrowed at base, cyme usually few-fld, the pedicels 2-10 mm; cal-lobes linear, 2-12 mm, less than 1 mm wide; cor pink (white) with a yellowish or greenish eye, the lobes oblanceolate, 8-13 mm; 2n=32. In variously wet or dry, open or wooded habitats, sometimes weedy; se. Va. to Tenn. and se. Mo., s. to Ga. and La. June, July.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.