65 



Page. 



40. Leaves with entire margins, 41 



40. Leaves vpith toothed margins, 44 



41. Leaves even-pinnate, Gleditsia and Gymnocladus in Leguminosae 177 



41. Leaves odd-pinnate 42 



42. Leaflets small, elliptic; twigs thorny Robinia in Leguminosae 181 



42. Leaflets large, ovate; twigs not thorny, 43 



43. Leaflets 7-21, not toothed at base, without glands, 



Rhus Vernix and R. copallina in Anacardiaceae 183 



43. Leaflets 11-41, sometimes with 2-4 blunt teeth at base which have glands on lower 



side at the point of each tooth, Simarubaceae 187 



44. Twigs and leaves prickly; leav4s twice or thrice compound, Araliaceae 199 



44, Twigs and leaves not prickly; leaves once compound, 45 



45. Large trees; staminate flowers in aments; fruit a .nut, Juglandaceae 100 



45. Small trees; staminate flowers not in aments; fruit red and fleshy, 46 



46. Leaflets 13-15; sap not milky; branches heavy-tipped 



Pyrus americana in Rosaceae 173 



46. Leaflets 11-31; sap milky; branches heavy-tipped, 



Rhus typhina and R. glabra in Anacardiaceae 183 



TABULATION OP GENERA AND SPECIES. 



Species. 



Families, Genera, etc. 



Gymnospermae. 



Fam. I. Pinaceae. 



Gen. 1. Pinus, 



Gen. 2. Larix, 



Gen. 3. Picea 



Gen. 4, Abies, 



Gen. 5. Tsuga, 



Gen. 6. Chamaecyparis, 



Gen. 7. Thuya 



Gen. 8. Juniperus, — 



Angiospermae. 



Fam. II. Salicaceae. 



Gen. 9. Salix, 



Gen. 10. Populus, 



Fam. III. Juglandaceae, 



Gen. 11. Juglans 



Gen. 12. Carya 



Fam. IV. Betulaceae. 



Gen. 13. Corylus, 



Gen. 14. Ostrya, 



Gen. 15. Carpinus, — 



Gen. 16. Betula, 



Gen. 17. Alnus, 



Fam. V. Fagaceae. 



Gen. 18. Fagus, 



Gen. 19. Castanea, 



Gen. 20. Quercus, 



30O 



34 



100 

 19 



5 

 15 



3 



a 

 1 



15 

 10 



4 (15)^ 

 4 



5 (1) 

 Ml) 



1 



5 



1 (1) 



1 



2 

 1^ 



5 



