Herbs, annual or winter-annual. Taproots slender. Stems ascending to erect, simple or branched, terete. Leaves forming basal rosette, connate proximally into sheath, petiolate (proximal leaves) or sessile (cauline leaves); blade 1-veined, oblanceolate to spatulate (proximal leaves) or elliptic to ovate (cauline leaves), somewhat succulent, apex acute. Inflorescences terminal, umbellate cymes, sometimes not yet developed in young individuals, then with 2-4 bracts and often buds at base of pedicel; bracts clustered, foliaceous with scarious margins to entirely scarious. Pedicels reflexed after flowering, erect in fruit. Flowers bisexual or occasionally unisexual and pistillate; perianth and androecium hypogynous; sepals 5, distinct, green, lanceolate to ovate, 2.5-4.5 mm, herbaceous, margins white, scarious, apex acute to obtuse, not hooded; petals 5, white to pink, clawed, blade apex jagged but not 2-fid; nectaries not apparent; stamens 3-5, arising from base of ovary; filaments distinct nearly to base; staminodes absent; styles 3(-5), clavate to filiform, 0.5-1.5 mm, glabrous proximally; stigmas 3(-5), subterminal to linear along adaxial surface of styles, minutely papillate (50×). Capsules ovoid to cylindric, opening by 6 (rarely 8 or 10) revolute teeth; carpophore absent. Seeds 35-60, orange to brown, oblong, shield-shaped, dorsiventrally compressed, papillate, marginal wing absent, appendage absent; embryo central, straight. x = 10.
Fls in terminal, pedunculate, cymose umbels; sep 5; pet 5, irregularly erose-fimbriate at the tip; stamens 3-10; styles 3; capsule thin-walled, ±cylindric, many-seeded, opening by 6 valves or apical teeth; seeds compressed, rough, attached by the inner face; annual or biennial herbs without stipules. 6, temp. Eurasia.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.