Slender, caulescent, rhizomatous aquatics, the stem villosulous with moniliform hairs, the rufous roots arising adventitiously from the lower nodes. Submerged leaves opposite or rarely ternate, the dissected blades flabellate in outline, 3-7 cm. long, 3-8 cm. broad, with 5-9 freely dichotomizing and trichotomizing divisions, the ultimate segments linear, 0.1-0.3 mm. broad, with weak subparallel venation, the petioles 1-3 cm. long; floating leaves, when present, narrowly to broadly elliptic. Flowers pink, purplish or white, tending toward yellow in the center, solitary on long axillary pedicels; sepals 3, oblong to obovate, obtuse, glabrous, exauriculate and exunguiculate, almost nerveless, 3-8 mm. long, 1-3 mm. broad, scarcely if at all connate; petals 3, narrowly to broadly oblong, obtuse or rounded, unguiculate, laterally auriculate, 3-8 mm. long; stamens 3-6, 2-5 mm. long, the oblong anthers extrorse; carpels (1-)2-3, 2-5 mm. long, separate, arcuate, glabrous to strigillose, mostly 3-ovulate, the style curved to the truncate or capitate stigma. Fruiting carpels banana-shaped, divergent, 1-3-seeded, the seeds ovoid, papillose, 1.5-2.0 mm. long, 1.0-1.5 mm. broad.