Description from Flora of China
Herbs, biennial or perennial. Stems erect, angulate and sulcate, usually echinulate or hispid along ridges. Basal leaves long petiolate, entire, 3-cleft, or pinnatipartite, usually dentate or lobed. Cauline leaves opposite, sessile or petiolate, usually 3-5-lobed, sometimes pinnatipartite or entire, both surfaces usually hispid, but glabrous or papillate-echinulate in some species. Capitula terminal, oblong, globose, or ovoid-globose; involucral bracts erect or spreading, leaflike, 1- or 2-layered, rostrate; involucels 4-8-ribbed, adnate to ovary; flowers bisexual. Calyx actinomorphic, shallowly disciform, 4-lobed, white pubescent. Corolla tubular, 4-lobed; lobes unequal in size. Stamens 4, inserted at corolla tube, alternate with corolla lobes. Gynoecium of 2 carpels; ovary inferior, enveloped by involucel; ovule solitary, pendulous, anatropous; style filiform; stigma oblique or lateral. Achenes surmounted with persistent calyx, enveloped by leathery involucel. Seed coat membranous; embryo imbedded in endosperm.
About 20 species: N Africa, Asia, Europe; seven species (two endemic) in China.