MEMOIRS OF THE NEW YORK BOTANICAL GARDEN. 215 



Montana: Lima, 1895, Rydberg, 26go; Little Belt Mts., 1896, 

 Flodman, 5/p and SS'^'^ Spanish Peaks, 551; Indian Creek, July 

 22, 1897, Rydberg & Bessey, 4.4.0^; East Boulder, 1887, Tweedy, 

 ly; Yogo, 1888, R. S. Willianis, yjj; 1883, Canby, loi. 



Yellowstone Park: Amethyst Mt., 1885, Tzvecdy, 4J0. 



Idaho: Mt. Chauvet, July 29, 1897, Rydberg & Bessey, 440J. 

 * PotentillaMacouniiRydb. Mem. Dept. Bot. Columbia Univ. 2 : loi. 



Resembles the preceding species, but has broader leaflets, which 

 are gra3'ish or whitish silky and slightly tomentose beneath. It grows 

 at an altitude of 3000 m. or more. 



Montana: Little Belt Mts., 1896, Flodman, jj6 ; Cedar Moun- 

 tain, July 16, 1897, Rydberg & Bessey, 4jg6 ; Bridger Mts., June 

 10, 4395 i Helena, 1882, F. Tzveedy. 

 Potentilla Hippiana Lehm. Nov. Stirp. Pug. 2: 7 [111. Fl. 2: 213; 



Man. R. M. 84; Rydb. Mon. 112]. 



This species belongs to the prairies and plains, perhaps reaching 

 an altitude of 1500 m. 



Montana: Silver Bow Co., Mrs. Moore; Great Falls, 1891, R. 

 S. Williams, yjd. 

 Potentilla Hippiana propinqua Rydb. Mem. Dept. Bot. Columbia 



Univ. 2 : 114 ; Potentilla diffusa Gra}', PI. Fendl. 41 ; not Willd. ; 



Potentilla Hippiana ptilckerrimaVf His. Proc. Am. Acad. 8: 555, 



in part [Coulter R. M. 84, in part] . 



This is a depauperate form of P. Hippiana with more crowded 

 leaflets and a less dense pubescence on the upper surface of the leaves. 

 It is a low plant with ascending stems, in habit much unlike P. piil- 

 cherrima, which it resembles in the form of the leaves. It is a com- 

 paratively rare plant, growing in dryer soil and perhaps extending 

 farther up into the mountains. 



Montana: Little Belt Mts., 1896, Flodnian, jjg; Cottonwood 

 Creek, j6o. 

 Potentilla effusa Dougl. ; Lehm. Nov. Stirp. Pug. 2 : 8 [Torr. & 



Gray, Fl. N. Am. i: 437; Man. R. M. 84; 111. Fl. 2: 214; 



Rydb. Mon. 114]. 



A plant growing on dry plains or hills, extending in the dryer 

 valleys up to an altitude of about 2000 m. 



Montana: Cottonwood Creek, 1896, Flodman, j^y; Indian 

 Creek, July 22, 1897, Rydberg & Bessey, 4398; Bridger Mts., June 

 14, ^jpp; Little Rocky Mts., i8S(), Dr. Havard ; Bozeman, 1887, 

 Tweedy, 18; Belt Mts., 1883, Scribner, 43. 



