Leaves ovate, abruptly pointed and acuminate or acute at apex, cordate at base, coarsely doubly serrate, glabrous or pilose on the under side of the midrib and veins, often furnished below with axillary tufts of pale hairs, 1½′—3′ long, 1′—2½′ wide; petioles glabrous or rarely villose, ½′—¾′ in length. Fruit: strobiles ¾′—2′ long and ¼′—½′ thick, on villose peduncles up to ¾′ in length; scales glabrous or pubescent. A tree rarely more than 30° tall, with slender glabrous or pubescent branchlets, and at high altitudes on the New England mountains reduced to a low shrub. Bark separating in thin layers, white or dark reddish brown. Distribution. Labrador and Newfoundland to northern New England, and westward to the shores of Green Bay, Wisconsin, and those of Lake Superior, Minnesota (Grand Marais, Cook County); on Mt. Mitchell, North Carolina, at an altitude of 5550° (_W. W. Ashe_). Betula papyrifera var. subcordata Sarg. _Betula subcordata_ Rydb. [Illustration: Fig. 201] Leaves ovate, acute or acuminate at apex, slightly cordate or rounded at base, rarely slightly lobed above the middle, finely often doubly serrate with teeth pointing forward or spreading, glabrous, 2′—2½′ long, 1′—1½′ wide; petioles sparingly villose or glabrous, ½′—¾′ in length. Fruit: strobiles drooping on slender peduncles 1′—1½′ long, about ⅓′ thick, their scales puberulous, ciliate on the margins, the middle lobe acute, rather longer than the broad truncate lateral lobes; nut obovoid, cuneate at base, 1/12′ long, narrower than its wings. A tree 25°—40° or occasionally 60° high, with a trunk 12′—18′ in diameter, and slightly glandular glabrous red-brown branchlets. Bark separating freely into thin layers, white or occasionally dark reddish brown or orange color. Distribution. Alberta (Crow Nest Pass, neighborhood of Jasper and Cypress Hills), through northern Montana and Idaho to western Washington, northeastern Oregon (Minum River Valley) and British Columbia. Betula papyrifera var. montanensis Sarg. _Betula montanensis_ Butler. [Illustration: Fig. 202] Leaves broadly ovate, acute at apex, truncate or rounded at base to oblong-ovate or lanceolate and long-pointed and acuminate at apex, narrowed and rounded at base, coarsely doubly serrate, thick, dark green above, paler, sparingly pubescent and furnished with conspicuous tufts of axillary hairs below, 3′—5′ long, 2′—2¼′ wide; petioles puberulous, ¾′—1′ in length. Flowers unknown. Fruit: strobiles cylindric, 1¾′—2′ long, ½′ thick, pendent on puberulous peduncles ½′—¾′ in length, their scales puberulous, finely ciliate on the margins, the slender base of those below the middle of the ament rather more than twice as long as the expanded upper portion of the scale.