d. Trunk and large branches armed with stout spines; 
leaflets 34-114 inches long...... GLEDITSIA, p. 165. 
dd. Trunk and large branches unarmed; leaflets 2-2%4 
inches long............... GYMNOCLADUS, p. 163. 
bb. Leaves opposite. 
c. Leaves pinnately compound; fruit a samara. 
d. Leaflets 3-5; samaras paired........... ACER, p. 172. 
dd. Leaflets 7-11, exceptionally 5; samaras not paired.... 
ss Sod aaa Gd chan spare ens atnalatadede neh wencace FRAXINUS, p. 21o. 
cc. Leaves digitately compound; fruit a prickly bur........ 
AESCULUS, p. 194. 
— XXVL — 
