5. Æsculus macrostàchya, Mx. (LONG-RACEMED BUCKEYE.) Leaflets 5 to 7, ovate, acuminate, serrate, velvety with hairs beneath. Flowers white, in long, slender, erect clusters; July; petals 4, spreading; stamens very long. A beautiful, widely spreading shrub. 5 to 18 ft. high; from the Southern States; often cultivated. Probably hardy throughout. GENUS =24. KOELREUTÈRIA.= A small tree with alternate, once to twice irregularly pinnate leaves with many coarsely toothed leaflets. Flowers conspicuous, yellow, in terminal panicles. In summer. Fruit rounded, bladdery, 3-celled, few-seeded pods; ripe in autumn. [Illustration: K. paniculàta.] =Koelreutèria paniculàta=, Laxm. Leaflets thin and very irregularly toothed. Clusters 6 to 12 in. long, of many irregular flowers, ½ in. wide; through the summer. Fruit an ovate, bladdery capsule, ripening in autumn. A fine, small, round-headed tree, 20 to 40 ft. high; from China. Probably hardy throughout. GENUS =25. ÀCER.= Trees, or rarely shrubs, with simple, opposite, and almost always palmately lobed leaves, which, in our species, are always deciduous. Flowers small and usually dull-colored, in clusters. Fruit double-winged and 2-seeded, in some species hanging on the tree till the leaves have fallen; in others dropping off early in the spring. The species differ much in the spreading of the wings of the fruit. Wood light-colored and medium hard; bark rather smoothish, but in large trees with longitudinal cracks. * Leaves slightly or not lobed 13. * Leaves about 3-lobed (rarely 5-lobed); shrubs or small trees. (=A.=) =A.= Leaves serrate 1, 2. =A.= Leaves somewhat sinuate, not at all serrate; juice milky. 10. * Leaves 5-, rarely 3-lobed. (=B.=) =B.= The lobes acute, irregularly but quite fully serrate; juice not milky. (=C.=) =C.= The fruit in corymbs, dropping early; American species. (=D.=) =D.= Leaf-notches somewhat rounded; tree large; limbs drooping on old trees 3. =D.= Leaf-notches acute; tree small 4. =C.= Fruit in hanging racemes, remaining on the tree till autumn; leaves thickish 5. =B.= The lobes acute; sparingly or not at all serrate. (=E.=) =E.= Juice not milky 6. =E.= Juice milky at the bases of the leaves 8, 9. =B.= The lobes obtuse and sinuate 10. * Leaves 5- to 7-lobed. (=F.=) =F.= Lobes fully serrate 11. =F.= Lobes sparingly serrate. (=G.=) =G.= Juice milky 8, 9. =G.= Juice not milky; leaves 8 to 10 in. broad 7.