XxXxViii KEYS—LEAVES ALTERNATE 
418. 
419. 
420. 
421. 
422. 
Twigs with narrow low ribs. 419. 
Twigs deeply corrugated or grooved. 420. 
Twigs sharply zig-zag. p. 152. Coronilla. 
Twigs not conspicuously zig-zag. p, 154. Caragana. 
Leaf-cushion without prominent ribs. p. 146. Cytisus. 
Leaf-cushion 3-ribbed. p. 147. Genista. 
Freely resiniferous when cut. p. 184. Pistacia. 
Without free-flowing sap or resin. 422. 
Seales 2: bundle-trace C-shaped. p. 303. Diospyros. 
Without this combination of characters. 423. 
. Buds not sealy: leaf-scars round. p. 138. Ceratonia. 
Without this combination of characters. 424. 
. Leaf-sears usually deltoid, as high as broad. 425. 
Leaf-scars usually broader than high. 432. 
. End-bud not enlarged if present. 426. 
End-bud distinctly larger than the lateral buds. 430. 
. Twigs glabrescent. 427. 
Twigs sparingly pubescent. 429. 
. Buds slightly glaucous: twigs red. p. 269. Elliottia. 
Buds not glaucous. 428. 
. Twigs reddish, becoming buff. p. 270. Zenobia. 
Twigs brown: buds very glossy. p. 288. Oxydendrum. 
Twigs gray. p. 286. Pieris. 
. Twigs moderate: evergreen or deciduous. p. 286. Pieris. 
Twigs very slender: evergreen. p. 291. Pernettya. 
. Outer scales of end-bud shorter than the bud. 431. 
Outer seales as long as the bud. p. 268. Clethra. 
. Bark shredding: capsules bristly. p. 275. Menziesia. 
Without this combination. p. 272. Rhododendron. 
. Soft-wooded or aromatic, iii) quickly 
branching. 433. 
Without this combination of characters. 435. 
. Buds solitary. 434. 
Buds often superposed: with stipules. p.176. Securinega. 
