152 ASH 



escence, whence a branch may appear dichotomous. Len- 

 ticels evident on the pale grey or brown twigs, against 

 which the red-umber buds show up strongly : scales broad 

 and not bordered. The leaf-scars vary from typical shield- 

 or hoof-shaped to more or less semi-lunate, and may have 

 5 9 leaf-trace scars (Fig. 59 6), not on a protruding leaf- 

 base or cushion. Pith round and white, shoots pubescent, 

 periderm passing to a thin scaly bark. 



The bud-scales are formed from the leaf-bases, and 

 occasionally the outermost i.e. the last formed leaves of 

 the previous season exhibit traces of the lamina as 

 appendages at their apices (Fig. 8). 



(b) Buds not viscid or glazed ; leaf-scars, or most of 

 them, not shield-shaped. 



(i) Buds depressed, conical, quadrangular, 

 velvety black ; twigs greenish grey, com- 

 pressed towards the tip, and nodose, owing 

 to the projecting leaf-bases, which bear 

 lunate or shield-shaped leaf-scars with one 

 curved series of fused leaf- trace bundles only. 



Fraxinus excelsior. Ash (Figs. 71 and 6, 59 x). The 

 stout smooth twigs are unevenly nodose owing to the pro- 

 jecting leaf-bases in the axils of which the stumpy black- 

 olive buds are somewhat buried; buds with but few scales 

 visible, the terminal larger bud showing 4. the smaller 

 lateral ones only 2 3, and frequently sub-opposite. Len- 

 ticels small, scattered and longitudinally extended. Fine 

 fissures on the grey branches. Dwarf-shoots very nodose 

 and curving up at the tips. Pith white and round. 



(ii) Buds neither conical depressed nor black 

 velvety; twigs neither compressed nor 

 nodose with projecting leaf-bases; leaf-scars 

 narrow, and transversely extended. 



