Distribution: Occurring chiefly west of the Cascades crest in Washington; British Columbia to California, east to central and eastern North America, where native.
Habitat: Lowland ponds and lakes.
Origin: Introduced from central and eastern North America
Conservation Status: Not of concern
Aquatic, perennial herbs from thick rhizomes, the leaves and flowers rising from the rhizomes.
Leaves floating, the blade deeply cordate, nearly orbicular, up to 25 cm. broad; petioles slender, terete, up to 2 m. long.
Flowers solitary, long-pedunculate, showy, white, tinged with pink, fragrant, opening in the morning and closing in the afternoon; sepals 4, greenish, 3-6.5 mm. long; petals white, 20-30, about equaling the sepals; stamens 50-100, yellow; style 1; stigmas 6-9, yellow, broad and spreading.
Fruit a berry-like capsule.