xxviii 



SHRUBS 



114. Leaves entire below. p. 51. Fothergilla. 

 Leaves crenate throughout. p. 51. Hamamelis. 



115. Buds sessile: bundle-trace one. 116. 



Buds stalked: bundle-traces 3. p. 26. Alnus. 



116. Flowers on leafy branches. p. 126. Sty rax. 

 Flowers in leafless racemes. p. 113. Clethra. 



113. Pith rather large, star-shaped. 118. 

 Pith small if grooved. 119. 



118. Buds crowded above, with several scales, p. 29. Quercus. 

 Buds not crowded, 2 exposed scales. p. 28. Castanea. 



119. Leaves 2-ranked, at least on spreading shoots. 120. 

 Leaves inserted in more than 2 ranks. 122. 



120. Twigs commonly bristly: fruit a nut. p. 23. Corylus. 

 Twigs and fruit different. 121. 



121. Pith 3-sided, small: flowers in catkins. p. 25. Betula. 

 Pith and inflorescence different. p. 59. Photinia. 



122. Nectar-glands on petiole or leaf-basie. p. 67. Prunus. 

 Leaves without nectar-glands. 123. 



123. Pith chambered. 124. 

 Pith continuous. 125. 



124. Leaves thin: fruit winged. p. 126. Halesia. 

 Leaves firm and revolute, sweet. p. 126. Symplocos. 



125. Leaves appearing entire except under lens. 126. 

 Leaves distinctly but mostly finely toothed. 128. 



126. Buds pressed into grooves in the stem. p. 119. Lyonia. 

 Buds not in grooves. 127. 



127. Branches long and slender. p. 54. Spiraea. 

 Branches short, green or granular, p. 123. Vaccinium. 

 Branches short, not green. p. 118. Leucothoe. 



128. Midrib with minute dark glands above, p. 57. Aronia. 

 Without such glands. 129. 



129. Bud-scale solitary, in front. p. 19. Salix. 

 Bud scales several. 130. 



