INDEX TO THE ARTIFICIAL KEYS 
Summer Keys: 
Key to the 
Key the 
Key the 
Key the 
Key the 
Key to the 
Key to the 
Key the 
Key the 
Key to the 
Key to the 
Key to the 
Key to the 
Key to the 
‘Key to the 
Key to the 
Key to the 
Winter Keys: 
the 
the 
the 
the 
the 
the 
the 
the 
the 
the 
the 
the 
the 
the 
the 
the 
the 
Key to 
Key to 
Key to 
Key to 
Key to 
Key to 
Key to 
Key to 
Key to 
Key to 
‘Key to 
‘Key to 
Key to 
Key to 
Key to 
‘Key to 
Key to 
genera, 
species 
species 
species 
species 
species 
species 
species 
species 
species 
species 
species 
species 
species 
species 
species 
species 
genera, 
species 
species 
species 
species 
species 
species 
species 
species 
species 
species 
species 
species 
species 
species 
species 
species 
XXxi. 
of Acer, 172. 
of Aesculus, 194. 
of Betula, 84. 
of Carya, 66. 
of Catalpa, 222. 
of Cornus, 202. 
of Fraxinus, 210. 
of Juglans, 60. 
of Picea, 18. 
of Pinus, 4. 
of Populus, 44. 
of Prunus, 152. 
of Pyrus, 142. 
of Quercus, 96. 
of Salix, 34. 
of Ulmus, 122. 
XXvil. 
of Acer, 174. 
of Aesculus, 195. 
of Betula, 85. 
of Carya, 67. 
of Catalpa, 223. 
of Cornus, 203. 
of Fraxinus, 211. 
of Juglans, 61. 
of Picea, 19. 
of Pinus, 5. 
of Populus, 45. 
of Prunus, 153. 
of Pyrus, 143. 
of Quercus, 98. 
of Salix, 34. 
of Ulmus, 123. 
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