WESTERN PLANE 231 



rib thinning out above, sinuous. Basals originating from 

 near the base of the laterals, of which they are branches, 

 and diverging at acute angles, running horizontally or 

 slightly backwards : they, like the laterals, giving off con- 

 spicuous outer branches, most of which run to the tips of 

 the lobes or large teeth. Secondaries sinuate, running to 

 the margin, the lower at angles of 40 50, the upper at 

 55 60. Tertiaries well developed and often as cross-ties. 

 Network very complete, the veins up to the fifth order 

 being distinguishable. 



EJ EJ Lobes broadly triangular, separated by 

 shallow wide sinuses extending only about 

 \ of the way in; almost tomentose below. 



Platanus occidentalis, L. Western Plane. Similar to 

 the last, but leaves 9 16 x 9 20 cm. in diameter, 

 usually truncate at the base ; lobes broader, and incisions 

 shallower and broader, and tomentum more persistent. 

 Venation as in P. orientalis. Petiole often red-brown, 

 3 10 cm. long. Stipules brown and woolly, caducous. 

 Leaves leather yellow to red-brown in autumn. 



For distinctions between the Planes and Maples see 

 p. 186. 



(2) Leaves not cut into lobes, but at most 

 coarsely toothed, or sinuate. 



(a) Leaves distinctly serrate, dentate or crenate. [For (b) 



(i) Leaves stipulate. [For (ii) 



[If the minute hair-like prolongations of the sheath of 

 the Barberry leaf are stipules, this species comes here. 

 The bush has spinose ciliate leaves. See p. 162. See 

 also note on p. 161.] 



(a) Leaves distichous on the long lateral 

 shoots. 



