Part 3 (1/2)

f. Fruit an acorn. QUERCUS, p.96.

ff. Fruit not an acorn.

g. Leaves fan-shaped, with many fine veins radiating from the base of the blade. GINKGO, p. 3.

gg. Leaves not fan-shaped, without many fine veins radiating from the base of the blade.

h. Leaf-lobes entire.

i. Leaf-petioles 5-6 inches long; leaves l.u.s.trous above; twigs not aromatic when bruised. LIRIODENDRON, p. 137.

ii. Leaf-petioles about 1 inch long; leaves dull above; twigs spicy-aromatic when bruised. Sa.s.sAFRAS, p. 139.

hh. Leaf-lobes sinuate-toothed to serrate.

i. Leaf-lobes coa.r.s.ely sinuate-toothed. PLATa.n.u.s, p. 141.

ii. Leaf-lobes serrate.

j. Branches armed with stiff, sharp thorns; sap not milky.

CRATAEGUS, p. 151.

jj. Branches unarmed; sap milky. MORUS, p. 135.

cc. Leaves opposite or whorled.

d. Margin of leaves entire or only slightly undulate.

e. Leaves 3-5 inches long; spray fine; fruit an ovoid, scarlet drupe. CORNUS, p. 202.

ee. Leaves 5-12 inches long; spray coa.r.s.e; fruit a long, slender-cylindrical capsule. CATALPA, p. 222.

dd. Margin of leaves serrate to lobed.

e. Margin of leaves finely serrate. VIBURNUM, p. 229.

ee. Margin of leaves distinctly lobed. ACER, p. 172.

aa. Leaves compound.

b. Leaves alternate.

c. Leaves simple-pinnate.

d. Branchlets armed with short, sharp p.r.i.c.kles. ROBINIA, p.

169.

dd. Branchlets unarmed.