Herbs , annual, caulescent; sap yellow. Stems leafy. Leaves: basal usually few, rosulate, indistinctly petiolate; cauline usually few and remote, alternate, proximal indistinctly petiolate, distal sessile; blade 2-3× pinnately lobed. Inflorescences axillary and terminal, 1-flowered; bracts present. Flowers: sepals 2, distinct; petals 4; stamens many; pistil 2-4(-6)-carpellate; ovary 1-locular; style absent or obscure; stigmas 2-4(-6), radiate. Capsules slenderly cylindric or terete, 2-4(-6)-valved, dehiscing from apex almost to base; peduncle straight or often recurved. Seeds many, aril absent.
Herbs, annual. Leaves bipinnatipartite, petiolate; lobes narrow; lobules linear, sometimes ovate-oblong, glabrous or pubescent. Flowers solitary, terminal, axillary, or terminal to leaf, pedicellate. Sepals 2, caducous, pubescent. Petals 4, purple, mauve, or red, overlapping in bud. Stamens many. Ovary terete, 2-4-carpellate, 1-loculed; styles short; stigmas capitate, 2-4-divided. Capsule narrowly terete, siliquose, (2-)4-valved, divided from apex to base. Seeds many, reniform, not carunculate, seed coat alveolate.
|[For Johann Jakob Roemer, 1819, Swiss physician and naturalist at Zürich]|