Bark and leaves not aromatic. Fruit dry, an acorn Quercus imbricaria in Fagaceæ 119 Fruit fleshy. Fruit with one seed, stone cylindrical Nyssa in Cornaceæ 259 Fruit with more than one seed, rarely one, seeds flat Ebenaceæ 265 B. Leaves finely serrate, coarsely toothed or lobed. C. Leaves with one primary vein. Bark and leaves aromatic Lauraceæ 163 Bark and leaves not aromatic. Staminate and pistillate flowers and fruit in catkins. Scales of winter buds 2, ovary many-seeded, seeds with a tuft of hairs at the summit Salix in Salicaceæ 34 Scales of winter buds more than 2, ovary 1-seeded, seeds without a tuft of hairs at the summit Betulaceæ 78 Staminate and pistillate flowers and fruit not in catkins. Fruit dry. Fruit a samara Ulmus in Ulmaceæ 137 Fruit not a samara Bark smooth; fruit spiny Fagaceæ 92 Bark furrowed; fruit a smooth capsule Ericaceæ 263 Fruit fleshy. Flowers more than 8 mm. (1/3 inch) broad, fruit edible, apple-like. Trees mostly with thorns, fruit with remnant of calyx at apex of fruit, normally with more than 1 seed. Malaceæ 171 Trees without thorns, fruit with no remnant of calyx at the apex, fruit a 1-seeded edible drupe. Amygdalaceæ 216 Flowers less than 8 mm. (1/3 inch) across, fruit a non-edible drupe Cornaceæ 259 C. Leaves with more than 1 primary vein. Staminate and pistillate flowers in catkins. Fruit dry Populus in Salicaceæ 45 Fruit fleshy Morus in Moraceæ 151 Staminate and pistillate flowers not in catkins. Pistillate and staminate flowers separate. Leaves 3-nerved at the base, fruit a 1-seeded drupe Celtis in Ulmaceæ 146