120 



ROSACEAE. 



CERCOCARPTJS. Mountain Mahogany. 

 (Family Rosaceae). 



Shrubs or small trees: ever- 

 green. Twigs terete, rather slen- 

 der, commonly forming dwarf 

 spurs closely covered by old leaf- 

 scars: pith minute, rounded. Buds 

 solitary, sessile, round, with 2 

 outer scales, quickly developing. 

 Leaf-scars alternate, minute, half 

 round, at top of the stipulate-base, 

 or transversely linear and low 

 with 3 bundle-traces after the fall 

 of this base. Leaves obovate, 

 flat and toothed, or lanceolate, re- 

 volute and entire. 



No one who has walked in the 

 western mountains in late summer 

 can have failed to have his atten- 

 tion drawn to one or other of the 

 species of Cercoparpus by the 

 clematis-like clusters of feathery 

 fruits that terminate its short 



twigs, and from which the name of the genus has been de- 

 rived. There is a marked contrast between the leaves of the 

 first two species and of the other 1 two. 



1. Leaves toothed and nearly flat. 2. 



Leaves entire and very revolute, varnished. 3. 



2. Teeth rounded: Rocky Mountains. (1). C. parvifolius. 

 Teeth pointed: California. (2). C. betulaefolius. 



3. Leaves minute (1X5 mm.), teretely revolute. 



(3). C. intricatus. 

 Leaves larger (25 mm. long), revolute at margin. 



(4). C. ledifolius. 



