Trees, shrubs or very rarely herbs. Leaves bipinnate, rarely unipinnate; stipules present, sometimes spinescent. Inflorescence generally a spike or umbel, rarely racemose or globose umbels; bracts small. Sepals usually 5, imbricate or valvate, generally fused together, toothed or lobed. Petals usually 5, valvate, free or fused, corolla lobed, hypo- or slightly perigynous. Stamens few to many, free or monadelphous or adnate to base of corolla tube; anthers versatile, often crowned by a deciduous gland. Pistil monocarpellary; ovary unilocular; ovules mostly numerous, style filiform; stigma terminal. Fruit dehiscent or indehiscent, sometimes schizocarpic; seeds mostly ovate to orbicular; aril rarely present.
A family of about 56 genera and nearly 2800 species, mainly distributed in tropics and subtropics of the world. 11 genera and 49 species are reported from West Pakistan. Of these only four genera and eighteen species are native and the rest are introduced.
Acknowledgements: We are grateful to the United States Department of Agriculture for financing this research under P.L. 480. Our grateful thanks are due to the authorities of the following herbaria for herbarium and library facilities: Royal Botanic Gardens, Kew; British Museum (Natural History), London; Royal Botanic Gardens, Edinburgh; Naturhistorisches Museum, Vienna; Gordon College, Rawalpindi and Forest Research Institute, Peshawar. The advice of Mr. J. P. M. Brenan (Kew), Mr. R.D. Meikle (Kew), Mr. B.L. Burtt (Edinburgh), Dr. W. T. Stearn (BM), Dr. K. H. Rechinger (Vienna), Dr. Anwar Kazmi (Peshawar) and Mr. Asghar Quraishi (Peshawar) is thankfully acknowledged.
