182 ROSACEAE. 



Leaves narrowly lanceolate, the margins entire, 



revolute. 1. C ledifolius. 



Leaves obovate to rounded, margins toothed 

 above. 

 Leaves obovate, pubescent or glabrous be- 

 neath. 2. C. betulaefolius. 

 Leaves oval to rounded, densely white downy 



beneath. 3. C. traskiae. 



L C. ledifolius Nutt. A shrub or small tree, 2-5 m. high; 

 leaves narrowly lanceolate, the margins entire and revolute, 15-35 

 mm. long, thick coriaceous, resinous and glabrate above, tomentose 

 beneath, narrowed at base to a short petiole; flowers sessile, tomen- 

 tose; calyx 4 mm. broad, deeply toothed, the tube becoming 6-10 

 mm. long; tail of the achene 5-8 cm. long in fruit. 



Inhabits the Arid Transition Zone from southeastern Washington 

 to southern California and Arizona: Mt. Wilson, Helm Geis; North 

 Baldy and Lone Pine Canyon, also in the San Bernardino Mountains. 



2. C. betulaefolius Nutt. A shrub or small tree, 2-5 m. high, 

 with rather thin flaky gray bark and spreading or somewhat re- 

 curved branches; leaves thick, obovate, cuneate, entire below 

 the middle, serrate toothed above, sometimes faintly so, distinctly 

 veined on both surfaces, smooth above, pubescent beneath; calyx 

 open campanulate, 6 mm. broad, the tube becoming 12-14 mm. 

 long in fruit, somewhat contracted above; achene coriaceous, the 

 plumose style about 7 cm. long. 



Rather common in the chaparral belt of all the mountains. 

 Flowering in March and fruiting in July. 



3. C. traskiae Eastw. A small tree 1-2.5 m. high, with rough 

 grayish brown bark and tomentose branchlets; leaves rounded to 

 oval, 2-6 cm. long, dark green and glabrous above, densely white- 

 tomentose beneath; calyx white-tomentose, 5-8 mm. broad, the 

 tube 1 cm. long; tail of achene about 5 cm. long. 



A rare species, known only from a small solitary grove in a 

 narrow precipitous canyon on Santa Catalina Island. 



8. ADENOSTOMA H. & A. Chamiso. 



Unarmed evergreen shrubs with small coriaceous en- 

 tire fascicled stipulate leaves and small white flowers in 

 terminal panicled racemes. Calyx obconic, 5-toothed, 

 10-striate. Petals 5, orbicular. Stamens 10-15, inserted 

 in bundles alternate with the petals. Pistil 1, simple; 

 style lateral; ovary 1-celled, 1-2-ovuled. Achene en- 

 closed by the hardened persistent calyx-tube. 



1. A. fasciculatum H. & A. Shrub 1-4 m. high with reddish 

 virgate branches and grayish bark, becoming shreddy; stipules 

 small, acute, leaves fascicled, linear-subulate, 4-8 mm. long, pun- 

 gently acute, glabrous, often resinous; flowers crowded, sessile; 

 calyx bracted at base, green, 2 mm. long, its lobes shorter than the 

 small petals; ovary obliquely truncate. 



Very common in the chaparral belt. April-June. 



