Annual or perennial scabrid herbs, without milky latex. Leaves simple, alternate or opposite, serrate, petiolate, usually palmately lobed; rarely undivided, stipules persistent or deciduous, incised. Flower unisexual (plants dioecious, rarely monoecious). Male inflorescence axillary, paniculate; female inflorescence cone like, spicate or crowded in the axil of large persistent foliaceous bracts. Male flowers: Perianth 5, free or slightly fused at the base, imbricate; stamens 5, erect in bud, adnate to tepals; filaments filiform, much shorter than the dithecous anthers, dehiscing longitudinally by short slits; pollen grains 3-porate, suboblate; pistillode absent. Female flowers: sessile; perigonium hyaline, entire, enclosing the ovary; ovary sessile, subglobose to ovate, unilocular with a single pendulous, anatropous ovule; styles 2, central, subulate or filiform, stigmatose inside. Fruit an achene or etaerio of achenes, compressed or flattened, enclosed by the persistent perigonium. Seed flattened with membranous testa; endosperm large and fleshy; embryo curved or spiral.