Dioecious or monoecious often poisonous, prostrate, erect or scandent annual, biennial or perennial herbs, shrubs or trees, succulent or not, spiny or unarmed, sometimes with phylloclades, with or without a milky latex or coloured sap. Indumentum 0 or of simple, branched or stellate hairs or peltate scales, the hairs sometimes urticating. Leaves usually alternate, sometimes opposite or whorled, occasionally all 3, green or scarious and squamiform, petiolate or sessile, stipulate or exstipulate, simple, lobed or compound, entire or toothed, peltate or not, palminerved or penninerved, glandular or eglandular. Stipules free or connate, sometimes spathaceous, membranaceous, capilliform, glandular or spiny, subpersistent to readily caducous. Inflorescences terminal, axillary, lateral or leaf-opposed, cymose, paniculate, racemose, spicate or cyathial, or with the flowers fasciculate or solitary. Flowers unisexual, usually actinomorphic and small to minute. Calyx in both sexes usually of 3-6 imbricate, valvate or open equal or unequal lobes or free sepals, often dissimilar between the sexes, rarely the ♀ calyx turbinate or spathaceous, sometimes accrescent, minute or O. Corolla in one or both sexes of 3-6 free (rarely united), subvalvate or imbricate petals, or petals minute or 0. Disc in the ♂ flowers of 5-6, occasionally more, free or united glands, or disc annular, cupular or 0; in the ♀ flowers hypogynous, usually annular or cupular, entire or lobed, rarely glands free, sometimes 0. Stamens (1-) 3-100 (-1000), free or connate, simple, rarely branched, anthers usually 2-locular and longitudinally dehiscent, erect or inflexed in bud, the cells usually parallel and adnate to the connective, sometimes free, variously positioned. Pistillode present or 0. Ovary superior, usually sessile, usually 3-celled; placentation exile, the ovules solitary or paired in each loculus. Styles usually 3, free or united, erect or spreading, entire, bifid or laciniate, the inner faces stigmatic. Staminodes sometimes present. Fruit usually schizocarpic, often dehiscing into 3 (occasionally less or more) bivalved cocci leaving a persistent columella, or else fruit indehiscent and drupaceous. Seeds 1 or 2 per cell, or by abortion 1 per fruit, carunculate or not, smooth or variously ornamented and sculptured, concolorous or variously patterned; endosperm usually copious and fleshy; embryo straight, radicle superior, cotyledons usually broad and flat (not Stenolobeae [not Pakistan]).
A very large family, the sixth largest amongst the Anthophyta, with 300 genera and 5000 species, subcosmopolitan but with the strongest representation in the humid tropics and subtropics of both hemispheres. Represented in Pakistan by 24 genera of which 11 are not native.
Acknowledgements: The financial assistance received from the United States Department of Agriculture under P.L. 480 with the coordination of the Pakistan Agricultural Research Council, Islamabad, is thankfully acknowledged.
