Stems flaccid, prostrate and creeping, or partly floating; lvs 0.5-3 cm, lanceolate to ovate, abruptly narrowed to a petiole about as long; fls minute, sessile, 4-merous, apetalous; fr oblong-obovoid, 3-4 mm, roundly 4-sided, the wall much thickened and corky below each sep, very thin below each sinus and revealing the outline of the seeds when dry; bracteoles minute or wanting; 2n=16. Creeping on mud and partly floating in shallow water; widespread in the n. hemisphere, and throughout our range.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
Frequent to common throughout the state, mostly in beds of ditches and small streams and on the muddy borders of ponds, swamps, sloughs, lakes, and streams. Sometimes in mucky soil in marshes.
