Pedicels 1–10(20) mm. long, slender to filiform, erect in flower, becoming deflexed to spreading in fruit.
Small, tufted, aquatic or marsh herb, of ten stoloniferous, rooting at nodes.
Corolla white with lobes pale blue or purplish beneath; lobes oblong, obtuse.
Calyx 2–2.5 mm. long, 5-lobed, lobes 0.5–1 mm. long, broadly ovate.
Petiole 25–40(110) mm. long, filiform in floating specimens.
Capsule 2.5–3 x 1.75–2 mm., ovoid-ellipsoid.