Fls perfect; tep 2 + 2, the inner broader; stamens 6, about equaling the tep; ovary flattened, with 2 short, divergent styles, the stigmas tufted; fr a flat achene surrounded by a broad, radially striate wing, cordate at base, subtended by the persistent, slightly enlarged tep, the 2 outer spreading, linear-oblong, the inner appressed, obovate-spatulate; perennial glabrous herbs with a stout, multicipital root, bearing several basal and few cauline lvs on long petioles, the blade broadly cordate to reniform; fls minute, in branching panicles; foliage acid. Monospecific.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.