xxxviii 



Keys Leaves Alternate 



420. 



p. 152. Coronilla. 



p, 154. Caragana. 



p. 146. Cytisus. 



p. 147. Genista. 



p. 184. Pistacia. 



Diospyros. 



418. Twigs with narrow low ribs. 419. 

 Twigs deeply corrugated or grooved. 



419. Twigs sharply zig-zag. 

 Twigs not conspicuously zig-zag. 



420. Leaf-cushion without prominent ribs. 

 Leaf-cushion 3-ribbed. 



421. Freely resiniferous when cut. 

 Without free-flowing sap or resin. 422. 



422. Scales 2: bundle-trace C-shaped. p. 303. 

 Without this combination of characters. 423. 



423. Buds not scaly: leaf-scars round. p. 138. Ceratonia. 

 Without this combination of characters. 424. 



424. Leaf-scars usually deltoid, as high as broad. 425. 

 Leaf-scars usually broader than high. 432. 



425. End-bud not enlarged if present. 426. 



End-bud distinctly larger than the lateral buds. ' 430. 



426. Twigs glabrescent.. 427. 



Twigs sparingly pubescent. 429. 



427. Buds slightly glaucous: twigs red. p. 269. Elliottia. 

 Buds not glaucous. 428. 



428. Twigs reddish, becoming buff. p. 270. Zenobia. 

 Twigs brown: buds very glossy. p. 288. Oxydendrum. 

 Twigs gray. p. 286. Pieris. 



429. Twigs moderate: evergreen or deciduous, p. 286. Pieris. 

 Twigs very slender: evergreen. p. 291. Pernettya. 



430. Outer scales of end-bud shorter than the bud. 431. 

 Outer scales as long as the bud. p. 268. Clethra. 



431. Bark shredding: capsules bristly, p. 275. Menziesia. 

 Without this combination. p. 272. Rhododendron. 



432. Soft-wooded or aromatic, deciduous, quickly 



branching. 433. 

 Without this combination of characters. 435. 



433. Buds solitary. 434. 



Buds often superposed: with stipules. p. 176. Securinega. 



