Annual, creeping and forming small mats on mud, with branches to 5 cm; lvs oblong to narrowly obovate, rarely over 4 mm; fls usually 2-merous; seeds basal-axile, erect, all terminating at about the same level, marked with narrowly elliptic areoles, the ends of the areoles not dovetailed with those of adjacent rows, and the longitudinal strips between the rows appearing distinct and straight under a hand-lens. Nf. to N.Y., w. to Ont. and Minn., s. along the coast to Md. and Va.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.