i6 



TREKS. 



76. Leaves thin, flat. 77. 



Leaves firm, revolute : fruit fleshy. Symplocos. 



77. Fruit dry, winged. Halesia. 

 Fruit fleshy. Diospyros. 



78. Buds naked. Rhamnus. 

 Buds scaly. 79. 



79. Leaves not lobed. 80. 

 Leaves lobed. 87. 



80. Leaves very woolly beneath, entire. Cydonia. 

 Leaves not woolly, or if so, toothed. 81. 



81. Leaves firm and glossy. 82. 

 Leaves thin and dull. 83. 



82. Pith with firmer plates. Nyssa. 

 Pith without firmer diaphragms. Oxydendrum. 



83. Leaves whitened beneath. Cornus. 

 Leaves not whitened unless by tomentum. 84. 



84. Without end-bud. Prunus. 

 With a terminal bud. 85. 



85. Buds elongated. 86. 



Buds short. Pyrus. 



86. Buds woolly. Sorbus. 

 Buds not woolly. , Amelanchier. 



87. Leaves pinnately lobed. Sorbus. 

 Leaves palmately lobed. Liquidambar. 



Compound. 



88. Leaves only once compound. 89. 

 Leaves often or always bipinnate. 103. 



89. Leaflets 3, close together. Laburnum 

 Leaflets several, distinctly pinnate. 90. 



90. Twigs stout, with large continuous colored pith. 91. 

 Twigs moderate, or pith chambered or pale. 93. 



91. Leaves with nectar glands : end-bud deciduous. Ailanthus. 

 Leaves not gland-bearing. 92. 



92. End-bud present. Cedrela. 

 End-bud absent. Gleditsia. 



93. Pith chambered, with thin brown plates. 94. 



Pith continuous or at most occasionally fissured. 95. 



