Il6 MEMOIRS OF THE NEW YORK BOTANICAL GARDEN. 



Montana: Cache Creek, 1885, Tzvccdy, -1-8 j ; Bozeman, Mrs. 

 AJdei'son; Emigrant Gulch, 1887, Rydberg & Bessey. 



Populus angustifolia James, Bot. Long's Exped. i : 497 [Man. 



R. M. 339; 111. Fl. i: 491]. 



The Black Cottonwood, Narrow-leaf Poplar or Balsam is common 

 along streams, up to an altitude of 2000 m. 



Montana: Livingston, 1889, Ticccdv : Boulder River, 1888, 

 Tzfccdy, 62; Missoula, 1882, Tzcccdy : Basin, 1892, Kclsey. 



Populus tremuloides Michx. Fl. Bor. Am. 2 : 243 [Man. R. M. 339 ; 



111. Fl. I : 492 ; Bot. Cal. 2 : 91] ; Populus trcniula Marshall, Arb. 



Am. 107, 1785 ; not Linn. 



The Quaking Aspen is rather rare in Montana, growing at an 

 altitude of 1000-3000 m. 



BETULACEAE. 



*Betula papyrifera ^Marshal, Arb. 19 [111. Fl. i : 509]. 



The Paper Birch, with white bark, is rather rare in Montana, and 

 found only in the northern part of the state, at an altitude of less than 

 1500 m. 



Montana: Columbia Falls, 1892, R. S. ]V/7l/ajjis, goj : Little 

 Rocky Mountains, 1889, Dr. V. Havard. 



Betula occidentalis Hook. Fl. Bor. Am. 2: 155 [Man. R. M. 332; 



111. Fl. I : 509; Bot. Cal. 2: 79]. 



Along streams in the mountain regions, up to an altitude of 2500 m. 



Montana: Emigrant Gulch, Aug. 23, 1897, Rydbcrg d- Bessey, 

 3g2g; Indian Creek, July 21, 3g2S ; Park Co., 1889, Tiveedy ; 

 Cinnabar, 1884, 2; Bozeman, 1886, 11S2; Great Falls and Belt 

 River Caiion, 1886, R. S. WiUiams., 404; Swimming Women Creek, 

 1882, Can by. 



Yellowstone Park : 1893, Addison Brozcn. 



Betula glandulosa ^Nlichx. Fl. Bor. Am. 2 : 180 [Man. R. M. 332 ; 



111. Fl. i: 510; Bot. Cal. 2: 80]. 



In mountain bogs and valleys, at an altitude of 1000-2500 m. 



Montana: Sun River, 1887, R. S. Williams, 638; Park Co., 

 1887, Tweedy, 2^3: Sheep Creek, 1883, Scribncr, 2jj ; Virginia 

 City, 1871, Haydcn ; Cut Bank Creek, 1883, Canby, 281. 



Yellowstone Park: Lone Star Geyser, Aug. 7, 1897, Ryd- 

 bcrg & Bessey, jg2-/ ; 1884, Tzucedy, i; 1885, 757. 



