Herbs usually annual or perennial, rarely biennial, sometimes cushion-or mat-forming, rarely slightly succulent. Rhizomes absent; roots fibrous or a slender taproot. Stems ascending, simple. Leaves in single or multiple basal rosettes, simple; petiole absent or obscure, slightly winged; blade lanceolate to spatulate or cuneate, base attenuate, cuneate, or truncate, margins entire or moderately dentate, apex acute to obtuse (often dentate), surfaces usually hairy, hairs grayish white, simple or forked. Scapes 1-25. Inflorescences umbels, 2-20-flowered, involucrate; bracts 1-10. Pedicels absent or erect to arcuate, elongating with age. Flowers homostylous; sepals 5, green, calyx broadly campanulate to subglobose or hemispheric, ± 5-angled, not keeled, glabrous, pilose, or puberulent, lobes shorter than tube; petals 5, white, sometimes fading to pink in age [pink to shades of red], corolla campanulate to salverform, tube yellow, ± inflated, lobes shorter than tube, apex emarginate to entire; stamens included; filaments indistinct, very short; anthers not connivent. Capsules globose to subglobose, valvate, dehiscent nearly to base. Seeds usually 3-4 in perennial species, 20-50+ in annual species, brown, 4-angled to somewhat trigonous, reticulate to almost smooth. x = 10.
More
Herbs perennial, annual, or biennial, acaulescent, rarely caulescent with ascending or decumbent shoots from a caudex. Leaves forming a rosette, rarely alternate; rosettes solitary or clustered, forming lax mats or compact cushions. Inflorescences umbellate, rarely a solitary flower, with bracts. Flowers 5-merous, homostylous. Calyx campanulate to subglobose, shallowly to deeply lobed. Corolla white, pink, purple, or dark red, rarely yellow; tube usually ± inflated, ca. as long as to shorter than calyx; throat constricted; lobes entire or emarginate. Stamens included, inserted on corolla tube; filaments very short; anthers ovate, apex obtuse. Style not longer than corolla tube. Capsule subglobose, dehiscing nearly to base. Seeds few to many.
Cal-tube obconic, equaling or exceeding the triangular lobes; cor salverform, constricted at the throat; stamens included; style very short; stigma capitate; capsule 5-valved, enclosed in the persistent cal; small winter-annuals with a rosette of basal lvs and one to several scapes bearing terminal, involucrate umbels of very small fls. 100, N. Temp. and Arctic.