=s.= Leaves very large (2 ft. or more long), about twice abruptly pinnate; leaflets broad and often 2 in. long; branches blunt; no thorns 33. _Gymnocladus._ =s.= Leaves and leaflets much smaller, leaves quite irregularly once or twice abruptly pinnate; branches slender-tipped; large tree, usually very thorny 34. _Gleditschia._ =s.= Leaves twice abruptly pinnate; leaflets over 400 in number, with midrib near the upper edge 35. _Albizzia._ =s.= Leaves regularly once pinnate, not over 2 ft. long. (=t.=) =t.= Leaves abruptly pinnate, not over 5 in. long; leaflets 8-12, small, mucronate-pointed 29. _Caragana._ =t.= Leaves odd-pinnate; shrub or small tree, with few, heavy-tipped branches; no spines or prickles 27. _Rhus._ =t.= Leaves odd-pinnate; leaflets large (3-5 in. long), not usually over 11 in number; round-topped tree 30. _Cladrastis._ =t.= Leaves odd-pinnate; leaflets less than 3 in. long, frequently 11-21 in number; often with spines at the bases of the leaves in the place of stipules 12. _Xanthoxylum_ or 31. _Robinia._ =u.= Leaves palmately compound. (=CC.=) =u.= Leaves pinnately compound. (=BB.=) =u.= Leaves simple, evergreen, sessile, in whorls around the stem, which they completely cover (98a. _Araucaria._) =u.= Leaves simple, opposite, evergreen, entire, over 2 in. long 61. _Osmanthus._ =u.= Leaves simple, opposite, evergreen, entire, under 1 in. long 73. _Buxus._ =u.= Leaves simple, deciduous. (=v.=) =v.= Branches ending in thorns; small trees, or shrubs. (=AA.=) =v.= Plants not thorny. (=w.=) =w.= Leaves palmately lobed (one variety, rarely cultivated, lacks lobes, but is heart-shaped with a serrate margin), the lobes over 3 in number, or with notches or serrations; fruit dry, winged 25. _Acer._ =w.= Lower leaves palmately 3-lobed, and heart-shaped at base, upper ones ovate, all with entire margin; fruit with juicy pulp covering the 4 seeds 66. _Clerodendron._ =w.= Leaves palmately lobed; fruit small, one-seeded, berry-like drupes in large clusters, with flattened stones, or large rounded clusters of flowers without stamens or pistils; shrubs rather than trees 47. _Viburnum._ =w.= Leaves heart-shaped, entire or slightly angulated; not lobed. (=DD.=) =w.= Leaves irregularly serrate, somewhat straight-veined; fruit single-winged; large cultivated tree 60. _Fraxinus._ =w.= Leaves neither heart-shaped nor lobed; small trees, almost shrubs. (=x.=)