=Myrtaceæ= dd) Stamens as many to twice as many as the petals: e) Stamens the same number and opposite the petals; mostly parasitic shrubs or trees; calyx usually much reduced. =Loranthaceæ= ee) Stamens the same number and alternate with the petals or more numerous: f) Anthers opening by a terminal pore; filaments often jointed; leaves often with 3-9 longitudinally parallel nerves. =Melastomataceæ= ff) Anthers opening by longitudinal slits; calyx mostly valvate; ovules 2 or more; fruits mostly winged; endosperm absent; flowers in heads, spikes, racemes or panicles. =Combretaceæ= cc) Herbs: d) Anthers opening by a terminal pore; leaves mostly with longitudinally parallel nerves; filaments often jointed. =Melastomataceæ= dd) Anthers opening by longitudinal slits: e) Ovules numerous on placentas pendulous from the apex of the 1-celled ovary. =Saxifragaceæ= ee) Ovules 1-4, pendulous from the top of the ovary cells. =Halorrhagaceæ= aa) Leaves alternate or all radical: b) Flowers unisexual: c) Flowers mostly zygomorphic; stamens mostly indefinite in number; no tendrils; stipules paired. =Begoniaceæ= cc) Flowers actinomorphic; stamens definite or rarely many, usually 3; anthers often curved or twisted; tendrils present or absent; no stipules. =Cucurbitaceæ= bb) Flowers hermaphrodite: c) Leaves stipulate: d) Herbs; leaves usually compound or much dissected, sometimes peltate; sepals very small; fruit composed of 2 indehiscent mericarps. =Umbelliferæ= dd) Trees or shrubs: e) Stamens the same number and opposite the petals; leaves entire or toothed. =Rhamnaceæ= ee) Stamens alternate with the petals or more numerous or fewer; flowers mostly in umbels; leaves compound, rarely simple; fruit a berry or drupe. =Araliaceæ= cc) Leaves exstipulate: d) Stamens as many as and opposite to the petals; often parasitic on other trees and shrubs; corolla usually brightly coloured. =Loranthaceæ= dd) Stamens alternate with the petals or more numerous; not parasitic: e) Herbs: