Fls perfect or unisexual, 4-merous, in racemes or heads. Per. petaloid, valvate, tubular in bud. Stamens opp. lobes, filaments adnate, ovary 1-celled, ovules 1 to several, style simple; fr. various, seeds often winged, endosperm 0. Trees or shrubs with us. alt. exstipulate lvs. Some 50 genera and over 950 spp., mostly of Australia and S. Africa.

Shrubs or trees. Lvs usually alternate, rarely whorled, mostly coriaceous, exstipulate, entire and simple or pinnately lobed. Infl. a spike or raceme, rarely an umbel or fls solitary, often with an involucre. Fls usually regular, sometimes irregular, usually ☿ (but spp. dioecious in ). Calyx petaloid, of 4 valvate segments, cohering lightly at first, later separating. Corolla 0. Stamens 4, opposite the calyx lobes and adnate to them; anthers generally sessile. Ovary superior, sessile or stipitate, 1-locular; hypogynous glands often present; ovules 1-many; style simple, often rigid and persistent; stigma usually prominent, sometimes oblique. Fr. usually an achene, nut, or coriaceous or woody follicle, rarely a drupe. Seed almost always lacking endosperm.