Succulent annual or perennial
herbs. Leaves alternate, flat, entire, with a closed basal sheath. Flowers
usually bisexual, regular, hypogynous in terminal panicle or axillary cymes.
Perianths of two series, each with three segments, the outer generally free,
green imbricate sepals, the inner equal petals in some petals fused into a
tube. Stamens 6, all fertile or 2 or more reduced to staminodes, filaments often
bearded, anthers often dissimilar. Ovary superior, of 3 or 2 fused carpels with
locules (rarely two), one to several orthotropous ovules, placentation axile.
Fruit a thin-walled dehiscent capsule, but rarely may be fleshy and
indehiscent. Seeds usually angled, surface smooth or rugose.