Height 25-40cm. Basal leaves petiolate, five to seven-lobed, each lobe cuneate and deeply toothed. Flowers solitary, greenish yellow, 2.5-5cm in diameter, sepals five to seven, sometimes toothed at the tip, spreading, petals many, much shorter than the stamens. North America, in swamps and bogs. T.l. var. albiflorus has white to cream flowers. Rocky Mountains.