Pale green annual 1-6 dm; stem 4-angled; lvs linear to narrowly oblong, mostly alternate, 1-2 cm, a few often elliptic and to 6 mm wide; fls pale purple to white, sessile, solitary or paired; hypanthium half as long as the subtending lf; stamens and pet 4-6, the pet cuneate, 2-3 mm; 2n=20. Mostly in wet soil, especially around salt-marshes; Me. to N.J. and e. Pa.; s. O.; also on the Pacific coast, in S. Amer., and widely distributed in the Old World. June-Sept.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.