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1 Leaves entire or with very obscure teeth (visible at 10×); petals 4-5 (-6), white, cream, or pink
..2 Petals 0; stamens 10-32; flowers numerous in dense globose or elongate spikes; leaves with a symmetric or asymmetric (oblique) base, the lateral veins marginal for a distance of at least 2-3 mm (F. major) or included in the blade tissue; [tribe Fothergilleae]
..2 Petals 4; stamens 4; flowers few in small clusters; leaves with a weakly to strongly asymmetric (oblique) base, the lateral veins included in the blade tissue or barely exposed for a distance of <1 mm; [tribe Hamamelideae]