Distribution. Moist soil near the banks of streams usually in mountain cañons; generally distributed, although nowhere very common: valley of the Saskatchewan (Saskatoon), Saskatchewan, westward to the basin of the upper Fraser and Pease Rivers, British Columbia, southward along the Rocky Mountains to eastern Utah, northern New Mexico and Arizona, the valleys of the Shasta region and the eastern slope of the Sierra Nevada, northern California, and eastward in the United States to the eastern foothills of the Rocky Mountains of Colorado, the Black Hills of South Dakota, and northwestern Nebraska. Passing into Betula fontinalis var. Piperi Sarg. _Betula Piperi_ Britt. [Illustration: Fig. 207] A tree occasionally 50°—60° high with a tall trunk 12′—18′ in diameter, short spreading branches, and usually longer and often narrower strobiles. Distribution. Spokane, Spokane County, Almota and Pullman, Whitman County, eastern Washington. 9. Betula Eastwoodæ Sarg. [Illustration: Fig. 208] Leaves broad-ovate to elliptic, acute, rounded or abruptly short-pointed at apex, coarsely serrate except at the cuneate base, thick, glabrous, dark green above, pale below, reticulate-venulose, the veinlets more conspicuous on the lower surface, 1′—1½′ long, ¾′—1½′ wide; petioles slender, glabrous ⅕′—⅓′ in length; stipules scarious, ovate-oblong, rounded at apex. Flowers: staminate aments usually solitary or in pairs, sessile, 1′—1¼′ long, ⅕′ thick, with broadly ovate pubescent dark red scales acute and apiculate at apex; pistillate aments ½′ long, about 1/12′ thick, with acute light green scales. Fruit: strobiles pendulous on peduncles ⅓′—½′ long, cylindric, ¾′ in length, about ⅙′ thick, their scales glabrous longer than broad, the lobes narrowed at the rounded apex, ciliate, the lateral slightly spreading, one third shorter than the terminal lobe. A tree 18°—20° high, with a trunk rarely more than 6′ in diameter, and slender red glabrous branchlets thickly covered with circular white glands. Bark close, chestnut-brown, marked by conspicuous horizontal white lenticels, about ⅕′ thick. Distribution. Swamps near Dawson, Yukon Territory, forming jungles with _Betula glandulosa_ Michx., _B. alaskana_ Sarg., and various Willows; as a large shrub in Jasper Park near Jasper, Alberta. 4. ALNUS L. Alder.