Herbs perennial, with tuberous rhizomes. Basal leaves 1 or 2, or absent, long petiolate, palmately divided. Scape unbranched; bracts several, verticillate, forming an involucre. Flower solitary, terminal, actinomorphic. Sepals 5--8, yellow, white, or pink-red, petaloid, oblong, elliptic, or ovate, caducous. Petals 5--8, tubular, small, shortly stalked, slightly concave or 2-fid, sometimes with sterile anthers. Stamens 10 or numerous; filaments narrowly linear, 1-veined; anthers ellipsoid or orbicular. Follicles 4--9, rarely more, usually stalked. Seeds many in a follicle, compressed globose, smooth or reticulate.