Description from Flora of China
Herbs annual or perennial, pubescent and/or glandular pubescent, rarely glabrous. Stems usually caespitose, sometimes slightly woody at base. Leaves ovate, elliptic, or lanceolate. Inflorescence terminal, a dichasial cyme, dense or lax, sometimes flowers solitary. Sepals (4 or)5, free. Petals (4 or)5, sometimes absent, white, apex usually 2-lobed or retuse, rarely entire. Stamens (3 or 5 or)10; nectaries present. Ovary 1-loculed; ovules numerous. Styles 3--5, inserted opposite sepals. Capsule golden yellowish, cylindric, sometimes subequaling but usually exceeding calyx, hard, thin, brittle, dehiscing by 2 × as many teeth as styles; teeth slightly curved, sometimes straight or revolute. Seeds numerous, globose or reniform, compressed, usually tuberculate; embryo annular.
The identities of the taxa to which the following three names apply could not be ascertained. All were described from China, but none of the types has been seen by the present authors: Cerastium calcicola Ohwi (Repert. Spec. Nov. Regni Veg. 36: 46. 1934), described from Taiwan; C. kaoi Shimizu (J. Fac. Text. Sci. & Techn. Shinshu Univ. No. 36, Biol., No. 12 [Stud. Limest. Fl. Jap. & Taiwan, Pt. 2]: 23. 1963), also described from Taiwan; and C. sinicum Nakai (J. Jap. Bot. 15: 526. 1939), described from Hebei.
The record of Cerastium perfoliatum Linnaeus in FRPS (p. 83), from Zhejiang, requires confirmation. No specimens of this species have been seen by the current authors.
About 100 species: almost cosmopolitan, most abundant in temperate and cold regions: 23 species (nine endemic) in China.
(Authors: Lu Dequan; John K. Morton)