ROSACE.E 535 



orange and bright scarlet; petioles slender, glandular near the base, with 2 or 3 large stipitate 

 dark red caducous glands, and about \' in length ; leaves at the end of vigorous shoots lanceo- 

 late, acuminate, coarsely serrate, often irregularly and deeply divided into 2 or 3 acute lateral 

 lobes, 3'-3f ' long, and If '-1|' wide. Flowers about f ' in diameter, on short slender pedicels, 

 in compact glabrous few or many-flowered corymbs; calyx-tube glabrous, the lobes nearly 

 triangular, entire, often bright red toward the apex; stamens 20; anthers small, yellow; 

 styles 5. Fruit ripening toward the end of September, on stout pedicels, in compact droop- 

 ing clusters, globose, f in diameter, dull vinous red and very lustrous when fully grown, 

 ultimately blue-black; calyx small, with reflexed persistent lobes; flesh thin, yellow, dry 

 and sweet; nutlets 5, thick, rounded and slightly ridged on the back, i'-fY long. 



A tree, occasionally 20 high, with a short stem, long slender spreading branches grace- 

 fully drooping at the ends, covered with bright red or reddish brown bark, separating on old 

 trunks near the ground into long slightly attached narrow plate-like gray scales, and slender 

 glabrous bright red lustrous branchlets armed with numerous straight slender spines f '-If 

 long; often forming clumps or small thickets with numerous stems 8-15 tall springing 

 from a single root. 



Distribution. Banks of the Cimarron, Gunnison, White, Tomichi, Eagle, San Juan, 

 and other Colorado streams on both slopes of the continental divide at altitudes of 

 6000-8000 above the sea. 



XVIII. MACRACANTRffi. 



Tomsntosce Sarg. 

 CONSPECTUS OF THE ARBORESCENT SPECIES. 



Leaves thin, with midrib and veins only slightly impressed on their upper surface; anthers 

 rose color or red. 

 Mature leaves pale pubescent below 7 . 



Leaves ovate to ovate-oblong; fruit in erect clusters, obovoid, orange-red; stamens 

 20. 140. C. tomentosa (A, C). 



Leaves ovate, oval, or obovate, in drooping clusters, globose to subglobose, bright 

 red or orange-red; stamens 5-10. 141. C. Chapmanii (A, C). 



Mature leaves glabrous (slightly pubescent on the midrib and veins below in 142). 

 Stamens 20. 



Leaves elliptic to suborbicular, smooth above; fruit in drooping clusters, subglobose 

 to short-oblong. 142. C. Gaultii (A). 



Leaves elliptic, scabrate above; fruit in erect clusters, subglobose. 



143. C. vegeta (A). 



Stamens 10; leaves ovate, scabrate above; fruit short-oblong. 144. C. Deweyana (A). 

 Leaves subcoriaceous to coriaceous, with midrib and veins deeply impressed on their upper 



surface and pubescent below. 

 Anthers rose color. 

 Stamens 20. 



Leaves elliptic, acute at the ends; fruit globose. 145. C. succulenta (A). 



Leaves broadly oval or obovate; fruit subglobose to short -oblong. 



146. C. gemmosa (A). 

 Stamens 10. 



Leaves broad-obovate or oval; fruit globose, villose at the ends; calyx-lobes coarsely 



glandular-serrate. 147. C. illinoiensis (A). 



Leaves broad-obovate to oval or rhombic; fruit subglobose; calyx-lobes entire. 



148. C. integriloba (A). 



Anthers yellow; stamens 10; leaves broad-obovate to elliptic or oval; fruit in erect 

 clusters, globose. 149. C. macracantha (A). 



