General:
Perennial aquatic herb from thick, erect rhizome; stems slender; stolons lacking.

Leaves:
Floating, arising from the summit of the rhizomes, long-stalked, without blotches or dots, heart-shaped, the blades 2-11 cm wide, 3-13 cm long.

Flowers:
Inflorescence of showy flowers that open in the morning and close in the afternoon, 3-7.5 cm wide; petals white, 10-17, equal to the sepals; sepals 2-3 cm long; stamens yellow; stigmatic disk margin appendages 3-4 mm long.

Fruits:
Berry-like capsules, leathery, many-seeded, rupturing irregularly with a jelly-like seed mass; seeds egg-shaped, 2-3 mm long, 1.5-2 mm wide.

Source:  The Illustrated Flora of British Columbia

If more than one illustration is available for a species (e.g., separate illustrations were provided for two subspecies) then links to the separate images will be provided below. Note that individual subspecies or varietal illustrations are not always available.

Illustration Source:  The Illustrated Flora of British Columbia

Synonyms and Alternate Names:
Castalia tetragona (Georgi) G. Lawson