BUCKTHORN FAMILY 555 





 Peduncles on leafy branches of the present season; leaves velutinous beneath. 



3. C. velutinus. 

 Leaf-blades oblong to elliptic or ovate, glandular-serrate to subentire. 



Umbels panicled, mostly terminal; leaves dull beneath, glabrate or villous. 



Leaves thin, glossy above, sparingly hairy when young, glabrate in age; pedun- 

 cles finely viscid-piiberulent. 4. C. ovatus. 

 Leaves thick, veiny, dull, as well as the peduncles more or less permanently 



villous. 5. C. pubescens. 



Umbels mostly axillary; leaves silky beneath. 



Leaf-blades distinctly glandular-serrate; plant not spiny. 6. C. subsericeus. 

 Leaf-blades obsoletely denticulate or entire; branches often ending in spines. 



7. C. Fendleri. 

 Leaves opposite, very small and thick, not triple-nerved. 



Leaves entire or nearly so; petals white. 8. C. Grcggii. 



Leaves spinulose-toothed ; petals bluish. 9. C. prostratus. 



1. C. sanguineus Pursh. Tall shrub, 1-3 m. high; young twigs greenish* 

 those of preceding season red or purple; leaf -blades oval, rounded at the apex, 

 rounded or cordate at the base, glabrate; petals white, spatulate; fruit obovoid, 

 3-lobed above, not crested, 4 mm. thick. Hillsides and copses: Mont. n 

 Calif. B.C. Submont. Ap-Jl. 



2. C. Martini M. E. Jones. Branched unarmed shrub, 1-2 m. high; twigs 

 and branches grayish, the former finely and closely pubescent; leaf -blades broadly 

 oval or subrotund, glabrous, except the veins beneath, minutely glandular- 

 dentate; inflorescence small, 1-3 cm. long; petals white, broadly spatulate. 

 Mountain sides: Utah Nev. Son. Submont. Je-Jl. 



3. C. velutinus Dougl. Shrub 1-3 m. high, with olive twigs and brown 

 branches; leaf -blades thick, broadly oval, often subcordate at base, glabrous and 

 shining above, pale and velutinous beneath, 4-8 cm. long; inflorescence panicu- 

 late, ample; petals white, broadly spatulate; fruit obovoid, 5 mm. in diameter, 

 deeply 3-lobed on the top. Hillsides: Mont. S.D. Colo. Utah B.C. Sub- 

 mont. Mont. My-Jl. 



4. C. ovatus Desf. Shrub 2-10 dm. high; branches brownish; leaf -blades 

 narrowly oblong to oval or ovate, 1.5-4 cm. long, serrate with gland-tipped teeth; 

 petals spatulate-dippershaped, 1.5-2 mm. long; fruit 4-4.5 mm. in diameter, 

 depressed globose, 3-lobed. C. ovalis Bigel. Sandy soil: Vt. Ga. Tex. 

 Colo. (Black Hills) S.D. Man. Plain Submont. Ap-Je. 



5. C. pubescens (T. & G.) Rydb. Shrub 5-10 dm. high; leaf-blades from 

 oblong to lanceolate or oval, 2-5 cm. long, glabrate except the veins above, vil- 

 lous beneath, glandular-serrate; petals white, 1.5 mm. long, spatulate; fruit sub- 

 globose, 5-6 mm. in diameter, slightly 3-lobed. C. ovatus pubescens T. & G. 

 Sandy soil: Mich. Mo. Tex. Colo. S.D. Plain Submont. My-Jl. 



6. C. subsericeus Rydb. Small shrub; leaves short-petioled; leaf-blades 

 elliptic or elliptic-lanceolate, acute at both ends, 2-3 cm. long, 3-ribbed, sparingly 

 strigose above, grayish-silky beneath; petals white, broadly spatulate, clawed, 

 1.5 mm. long; fruit dark brown, about 4 mm. in diameter, slightly 3-lobed above. 

 Foot-hills: Colo. Submont. Jl. 



7. C. Fendleri A. Gray. Low spinescent shrub, 1-5 dm. high, with canescent 

 twigs; leaf-blades elliptic, 3-ribbeoV entire-margined, 7-30 mm. long, green and 

 strigose or glabrate above, pale and silky-canescent beneath; petals white, 1.5 

 mm. long, spatulate; fruit 4 mm. wide, subglobose, somewhat 3-lobed. Woods 

 and hillsides: S.D. N.M. Ariz. Utah Wyo. Submont. Mont. Je-Au. 



8. C. Greggii A. Gray. Intricately branched spinescent shrub, 1-2 m. 

 high; branches gray or olive-green, at first finely tomentose; leaves short-petioled; 

 blades 5-15 mm. long, 1-ribbed, elliptic or oval, entire or nearly so, coriaceous, 

 glabrate above, tomentulose beneath; petals white, oboyate-spatulate, 1.5 mm. 

 long; capsule slightly elongate, 4 mm. in diameter. Arid mountain sides: Tex. 

 Nev. Mex. Son. F-Je. 



9. C. prostratus Benth. Intricately branched prostrate shrub; leaves 5-25 

 mm. long, coriaceous, obovate or oblong-cuneate, spinulose dentate, glabrous or 

 puberulent, pale beneath; petals bright blue, broadly obovate; capsule subglo- 

 bose, about 5 mm. thick. Mountains: Ore. Ida. Nev. Calif. Submont. 

 Mont. Ap-Je. 



