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.
A small family of 2 genera and 3 species, distributed in the north temperate zone of the world; represented in West Pakistan by 2 genera and 2 species.
Acknowledgements: We are grateful to the United States Department of
Agriculture for financing this research under P.L. 480. Thanks are also due to Mr. B.L. Burtt of the Royal Botanic Gardens, Edinburgh, for his helpful suggestions.