Annuals, glabrous or with scattered bladder hairs (mostly at abaxial side of leaves). Leaves entire, undulate or lobate, rhombic, triangular or oblong in shape. Inflorescence consists of dense glomerules, cylindrical, with lateral branches mostly appressed to stem. Perianth of 2-5 free or diversely connate hyaline or greenish segments (in some species both perianth forms are present). Flowers hermaphrodite or (lateral ones) sometimes female. Stamens 1-5. Stylodia (= style-like stigmas) 2. Pericarp thin, 1-layered or very rarely of several equal layers, smooth, mamillate or rarely papillate. Seeds mostly small, up to 1.2 mm. in diam., red or black. Outer seed-coat layer (testa) with stalactites.