Perennial or rarely annual, dwarf scapose herbs. Leaves radical, linear, usually crowded at the base. Scape erect. Flowers unisexual, actinomorphic, numerous, small, sessile or shortly pedicellate on a variously shaped receptacle; the male and the female flowers often mixed in dense terminal capitula, rarely on separate heads. Perianth scarious or membranous, 2-3-merous in 2 whorls, the outer free or rarely partially connate, the inner cupular or sometimes absent. Male flowers: stamens free, opposite the segments, the same or twice (4-6), the number of perianth segments; anther 1-2-celled, dehiscing longitudinally. Female flowers: ovary superior, 2-3-locular with a single orthotropous, pendulus ovule in each locule. Style long, stigma 2-3-fid. Fruit a loculicidal capsule. Seeds endospermic.