KEY TO GENERA AND SPECIES 37 



68. Leaves opposite 69. 



68. Leaves alternate 70= 



69. Wing of the fruit unsymmetrical, thickened at 



one edge. Leaflets usually 3 or 5. Western 

 New England southward and westward, 

 also cult, and escaped Box Elder, Ash- 

 leaved Maple, 186. 



69. Wing of fruit symmetrical, not thickened at 



one edge. Leaflets usually 7 or 9 Ash, 202. 



70. Margins of leaflets more or less regularly 



toothed, at least above the middle. (See 

 Figs. 204, 234.) 73. 



70. Margins of leaflets without teeth, at least none 



above the middle. (See Figs. 57, 235.) 71. 



71. Leaflets commonly with one or more irregular 



teeth or notches near the base. Fruit nearly 

 2 inches long, very thin, with one seed near 

 the middle. Cult, and escaped. Native in 

 China. (Figs. 57, 58.) Tree of Heaven, 

 Ailanthus, Chinese Sumach, Ailanthus 

 glandulosa Desf. 



71. Leaflets without the basal teeth. Fruit flat- 

 tish, usually at least 2 inches long, several 

 seeded 72. 



71. Leaflets without the basal teeth. Fruit globu- 



