Cerastium L.
Annual or perennial herbs, sometimes subshrubs. Hairs usually dense, glandular and/or eglandular, rarely 0. Lvs opposite, exstipulate. Infl. cymose, sometimes reduced to solitary fl.; bracts and sepals herbaceous or with narrow to wide scarious margins; epicalyx 0. Sepals 5, free. Petals 5, white, emarginate or 2-fid up to ⅓ way, rarely 0; coronal scales 0. Stamens usually 10, sometimes 8, 5 or fewer. Styles (3)-5-(6). Fr. a cylindric capsule, often curved, dehiscing by twice as many short apical teeth as the styles, sessile. Seeds many, obovoid, spherical or reniform, tuberculate, not winged.
Key
c. 100 spp., cosmopolitan, especially temperate. Naturalised spp. 5.
Important characters for identification of the spp. are the types of hairs on the sepals and whether they overtop the sepal apex (Fig. 49), and also the length of the petals and styles.