Annual or perennial herbs (in ours), often fleshy. Stipules 0. Leaves alternate, rarely opposite, simple. Flowers minute, usually green or grey, bisexual or unisexual, actinomorphic. Perianth 2-5-lobed, persistent. Stamens as many as, or fewer than, the number of perianth segments. Ovary superior or half-inferior, 1-locular. Stigmas 2(-5). Fruit usually an indehiscent achene.