Large trees to shrubs. Buttresses absent. Spines absent. Stilt roots absent. Bark gray, brown; not peeling in strips. Slash brown. Vertical stripes in the inner bark or wood absent. Odor absent. Exudate absent. Terminal buds not enclosed by leaves.
Complex hairs absent. Stinging hairs absent. Mature twig indumentum absent.
Leaves whorled; 3-10 per whorl; not scale-like; compound; pinnate; without a terminal leaflet, or with a terminal leaflet; leaflets opposite, or leaflets alternate; all of the same type; not modified into spines; coriaceous; not gland-dotted; very asymmetric at the base, or symmetric at the base; not dissected; smooth margined. Epidermis waxy. Venation pinnate. Secondary veins open, or closed; prominent. Smallest veins prominent, or not prominent, but visible; net like, or ladder like. Intramarginal vein present. Stalk of blade absent to less than a quarter the length of the blade; winged; attached to base of leaf blade; not swollen. Stipules absent. Domatia absent. Basal glands absent. Hairs on mature leaf absent.
Inflorescences present; terminal; on a branched axis; specialized inflorescence units absent; numerous and persistent inflorescence bracts absent. Flowers bisexual; stalked; with the parts barely visible to the eye to about 0.5 cm long or across; with male or female parts not raised on a column. Hypanthium absent. Perianth present; with distinct calyx and corolla whorls. Sepals 5; partially joined; not persistent in fruit; not growing any further after flowering. Epicalyx absent. Petals present; 5; all joined; not fleshy; deciduous; not stalked; entire. Stamens 2; filaments present; free of each other; joined to the perianth; all equal in size; anisomerous. Anthers 2 loculed; attached along the side; not awned; dehiscing by long slits. Ovary superior. Carpels joined; 4. Locules 4. Styles solitary. Stigmas 1 lobed; not distinctive. Fruit capsular; non-fleshy; not multiple; splitting; not enclosed in, or sitting on, fleshy perianth parts; wingless. Seeds 100 per fruit (many); barely visible; wingless; uniform in cross-section; aril absent; non-endospermic.
Twigs four-angled; petiole winged but leaflets sessile; leaflets increase in size from base to top of leaf; young leaves purple; flowers tiny; stamens 2; fruit a capsule. Taxon images: genperon.gif
Cite this publication as: Jarvie, J.K. and
Ermayanti (1996 onwards). `Tree Genera of Borneo - Descriptions and
Dallwitz (1980) and Dallwitz, Paine and Zurcher (1993) should also be cited.