434 ROSACEAE 



obovate to elliptic, 1.5-2 cm. long, obtuse; pistils numerous; styles in fruit 3-4 

 cm. long. Hills and canons: Tex. — Colo. — Utah — Ariz.; n Mex. Son. — Mont. 

 Ap-Au. 



30. COWANIA D. Don.. Cliff Rose. 



Shrubs or small trees. Leaves alternate, toothed or pinnatifid, or entire, 

 coriaceous, glandular-dotted, mostly with revolute margins and tomentulose 

 beneath. Flowers solitary, terminal, on short branches. Hypanthium wholly 

 persistent, more or less tm-binate. Sepals 5, imbricate, persistent. Petals 5, 

 obovate, spreading. Stamens numerous in two series, inserted in the throat of 

 the hypanthium. Pistils 4—12, or in one species only 1-3, distinct, sessile, 

 densely villous-hirsute; 8t5de terminal, plumose, persistent, elongate in fruit; 

 ovules solitary. 



1. C. Stansburiana Torr. A shrub 1-3.5 m. high; bark of the stem gray 

 and shreddy, that of the young branchlets reddish-brown and glandular; leaves 

 obovate in outhne, 8-15 mm. long, glandular-punctate and green above, more or 

 less tomentulose beneath, revolute-margined, pinnately 3-5-divided; flowers 

 sohtary, terminal; hypanthium turbinate-funnelf orm ; petals sulphur-yellow or 

 cream-colored, broadly obovate, 8-10 mm. long. C. mexicana A. Gray, not D. 

 Don. Dry hills: KM. — s Colo. — Nev. — s Calif.; n Mex. Son. — Submont. 

 My-N. 



31. PtJRSHIA DC. 



Shrubs, with spreading branches. Leaves alternate, crowded, apparently 

 fascicled, deeply 3-cleft, with revolute margins. Flowers sohtar}^ terminating 

 short branches. Hyj^anthium turbinate or funnelform, persistent. Sepals 5, 

 imbricate. Petals 5, yellow. Stamens about 25, in one series, inserted on the 

 margin of the hypanthium. Pistils 1, rarely 2, lance-oblong, tapering into a 

 short persistent style, which does not greatly elongate in fruit; ovule soUtary, 

 basal, erect. [Kumia Spreng.] 



1. P. tridentata (Pursh) DC. Shrub 1-3 m. high; bark chestnut-brovsTi or 

 grayish; leaves cuneate in outhne, 5-30 mm. long, 3-lobed at the apex, white- 

 tomentose and revolute-margined beneath, glabrate or slightly tomentose above 

 when young; flowers solitary; hypanthium funnelform; sepals oblong or elUptic; 

 petals spatulate-obovate, 7-9 mm. long. Hills: Mont. — N.M. — Calif. — B.C. 

 Son. — Submont. My-Au. 



32. CERCOCARPUS H.B.K. Mountain Mahogany. 



Shrubs or trees with hard wood. Leaves alternate, simple, toothed or entire- 

 margined. Flowers axillary, solitary or fasciculate. Hypanthium with a cylin- 

 dric persistent tube, abruptly widening into a tiu-binate or campanulate, 

 deciduous limb. Sepals 5, from broadly triangular to nearly subulate. Corolla 

 wanting. Stamens iS or more, inserted at different heights on the limb of the 

 hypanthium. Pistil solitary, inserted in the bottom of the hypanthium; ovary 

 cyhndric-fusiform, sessile; style terminal, elongate, plumose; stigma undivided, 

 terminal. Seed cylindric, solitary, basal. 



Leaves serrate or dentate. 



Hypanthium and leBves villous, with spreading hairs; leaves broadly obovate, 1.5-3 



cm. long. 1. C. 7nonlanus. 



Hypanthium and leaves appressed-silky. 



Leaves obovate-flabelliform, 1-2 cm. long. 2. C. flabellifolius. 



Leaves oblanceolate or obovate, 2-4 cm. long. 3. C. argenlcus. 



Leaves entire, from linear to elliptic, coriaceous, with more or less revolute margins, 

 resinous. 

 Leaf-blades 1.5-3 cm. long; tail of fruit 4-6 cm. long. 



Leaf-blades elliptic, only slightly revolute, in age merely tomentulose beneath; 



petioles 3-5 mm. long. 4. C. Icdifolius. 



Leaf-blades Unear, strongly revolute, permanently white villous-tomentose be- 

 neath; petioles 1-2 mm. long. 5. C. hypoleucus. 

 Leaf-blades 5-15 mm. long, narrowly linear, strongly revolute, only the midrib of the 

 lower sm-face exposed; tail of fruit 3-4 cm. long. 

 Leaves short-villous when young. 6. C. arizonicus. 

 Leaves glabrous from the beginning. 7. C. intricatus. 



