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..
Perennial herbs, with short leafy caudices and solitary or clustered scapes, and basal entire or toothed leaves, the flowers in terminal compact or open compound cymes. Calyx-lobes 5, erect or reflexed. Corolla white or mainly so, essentially regular, the petals clawless or rarely clawed. Stamens 10; filaments subulate or clavate. Ovary slightly inferior, the carpels slightly united. Follicles spreading or with spreading tips. [Greek, small-flower.]
About 65 species, natives of the north temperate and boreal parts of both hemispheres. Type species: Micranthes semipubescens Haw. *
Filaments subulate or filiform-subulate; petals not yellow-blotched.
Cymules wholly or mainly aggregated into a head; follicles red.
Cymules in pyramidal or corymb-like panicles; follicles green.
Corolla white; petals broad; calyx-lobes not reflexed at maturity.
Cymules permanently compact; petals not twice exceeding the calyx.
Cymules ultimately lax; petals more than twice exceeding the calyx.
Corolla greenish; petals narrow; calyx-lobes reflexed at maturity.
Filaments clavate; petals yellow-blotched.
Leaves with elongated blades.
Leaves with short or suborbicular blades.
Leaf-blades narrowed at the base; neither cordate nor of an orbicular type.
Leaf-blades cordate at the base, orbicular or nearly so.
Saxifraga nivalis L. Sp. Pl. 401. 1753.
Micranthes nivalis Small, N. A. Flora 222: 136. 1905.
Seldom over 6' high. Scape viscid, naked, or bracted at the base of the capitate sometimes branched inflorescence; leaves ovate or oval, narrowed into a margined petiole, thick; flowers white, 3"-5" broad, in a compact cluster; calyx-lobes ovate or oblong, spreading, obtuse, about one-half the length of the oblong or oblong-ovate petals; ovary half-inferior; follicles deep purple, divergent.