Stem erect or ascending, 2-5 dm, not much branched, glabrous; lvs oblanceolate, 2-4 cm, serrate above the middle, cuneate at base; pedicels 1-3 cm, ascending, the basal bractlets shorter than the subtending lvs; cal 6-9 mm; sep narrowly lanceolate, attenuate, the outer twice as wide as the inner; cor 1 cm, white with purple lines on the lower lip; 2n=42. Moist woods; Del. and Md. to Ky. and Mo., s. to Fla. and Tex. All summer. (Bacopa a.; Pagesia a.)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.