Annual to perennial herbs; hairs glandular or 0. Lvs opposite, exstipulate, linear-subulate to lanceolate to spathulate, often glaucous, often sub-fleshy; cauline lvs connate in pairs. Fls in cymes, panicles or capitula; bracts leaflike to subulate; epicalyx 0. Calyx bell-shaped or top-shaped, rarely cylindric, not ribbed, 5-veined, 5-toothed with broad scarious nerveless commissures between the veins. Petals 5, white to pink, tapered or narrowly clawed, entire or emarginate; coronal scales 0. Stamens 10. Styles 2. Fr. a globose to cylindric capsule dehiscing by 4 teeth; carpophore very short or 0. Seeds auriculate, compressed.