Sep somewhat petaloid, colored within; stamens 12-18, or reputedly to 36; filaments of 2 lengths; anthers introrse, pistils 4-8; submerged parts covered with a mucilaginous jelly; lvs alternate, mostly crowded near the summit, long-petioled, with floating, centrally peltate blade. Monospecific
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.