Perennial or annual herbs or shrubs or trees, rarely small herbs (the latter sometimes saprophytic). Leaves simple, alternate, opposite, or whorled, petiolate or sessile, papery or leathery, with pinnate veins, margin entire, leaves rarely reduced and scalelike; stipules absent, sometimes spiniform or scalelike appendages present. Flowers bisexual, zygomorphic, white, yellow, or purple-red, pedicellate or sessile, in axillary or terminal racemes, panicles, or spikes, with bracts and usually also with bracteoles. Calyx persistent or caducous; sepals 5, free or connate at base, outer 3 small, inner 2 (alae) large, petal-like, or all 5 nearly equal. Petals 3 or 5, basally often connate, lower (median) one ("keel") usually inflexed, carinate, sometimes with fimbriate or lamellate or papilionaceous apical appendages. Stamens 8, 7, 5, or 4; filaments free, or variously united and forming a sheath open on upper side and troughlike; anthers basifixed, usually dehiscing by a single apical pore. Disk usually absent, if present annular or glandular. Ovary superior, 1- or 2-loculed; ovule 1 per locule, anatropous, pendulous, rarely ovules numerous and placentas parietal; style 1, erect or curved; stigmas 1 or 2, capitate. Fruit a 2-loculed capsule, dehiscing by valves, or a 1-loculed samara or a berrylike drupe, dehiscing or not. Seeds 2, or 1 with 1 sterile locule, yellow-brown, dark castaneous, or black, ovoid, globose, or ellipsoidal, glabrous or piliferous, strophiolate or not, with or without endosperm, sometimes with an appendage at end opposite to strophiole.
Thirteen to 17 genera and about 1000 species: widespread worldwide, especially in tropical and subtropical regions of both hemispheres; five genera and 53 species (24 endemic) in China.
Chinese genera of economic importance include Polygala (medicinal), Salomonia (medicinal), Securidaca (medicinal), and Xanthophyllum (fine wood).
Chen Shukun. 1997. Polygalaceae. In: Chen Shukun, ed., Fl. Reipubl. Popularis Sin. 43(3): 132-203.