This section is from the book "An Illustrated Flora Of The Northern United States, Canada And The British Possessions Vol2", by Nathaniel Lord Britton, Addison Brown. Also available from Amazon: An Illustrated Flora of the Northern United States, Canada and the British Possessions. 3 Volume Set..
Glabrous perennial scapose herbs, with short rootstocks, basal petioled entire leaves, usually with a single sessile leaf on the scape, and solitary terminal white or pale yellow flowers. Calyx 5-lobed nearly to the base, its short tube free from or adnate to the ovary. Petals 5, spreading, marcescent, each with a cluster of gland-tipped staminodia at the base, united into a scale below, or distinct. Fertile stamens 5, alternate with the petals. Ovary superior or half inferior, 1-celled; style very short or none; stigmas usually 4; ovules 00. Capsule 1-celled, with 3 or 4 placentae projecting within, loculidically 3-4-valved. Seeds numerous. Seed-coat winged.