212 MEMOIRS OF THE NEW YORK BOTANICAL GARDEN. 



Montana: Bozeman Canon, 1895, Rydberg, 26^2; Bozeman, 

 iSg6, Flodman, J64; Spanish Basin, June 23 and 28, 7?v<^<^f^'^' <^ 

 Bessey, 4j'/8 and 4381 ; Gallatin Co., 1887, Tweedy, 64. 



Yellowstone Park: 1885, Tweedy, 464. 



*Potentilla viridescens Rydberg, Mem. Dept. Bot. Columbia Univ. 



2 : 69. 



Intermediate between the preceding and the followijig. In gen- 

 eral habit it resembles the latter, but the leaves are slightly to- 

 mentose beneath, and the calyx more hairy. Its habitat is similar to 

 that of the preceding. 



Montana: Spanish Basin, 1896, Flodnian, j66 ; Little Belt 

 Mts., j6y; Pony, July 6, 1897, Rydberg & Bessey, 4382; Electric 

 Peak, Aug. 18, 43^6. 



Yellowstone Park: 1885, Tweedy, 464. 



Potentilla Nuttallii Lehm. Ind. Sem. Hort. Hamb. 1852 : 12 [Rydb. 



Mon. 70] ; Potentilla gracilis rigida Wats. Proc. Am. Acad. 8: 



557 [Man. R. M. 85 ^Bot. Cal. i : 179] ; not P. rigida Wall. . 



Grows in the open valleys, at an altitude of 1000-2000 m. 



Montana: Spanish Peaks, 1896, Flodnian, 363; Spanish Basin, 

 June 28, 1897, Rydberg & Bessey, 4384; July i, 4383 ; Jack Creek, 

 July 14, 4383; Cottonwood, 1892, W. T. Shaw; Bozeman, 1887, 

 Tweedy, 13; Fort Ellis to Yellowstone, 187 1, R. Adams (Hayden 

 Survey). 



Yellowstone Park : 1884, Tzvecdx, gy. 



* Potentilla pectinisecta Rydberg, Bull. Torr. Bot. Club, 24: 7 



[Mon. 73]. 



Has the same habit as P. Candida and P. fastigiata, but the 

 leaves are deeply dissected into linear lobes : they are silky on both 

 sides and only slightly tomentulose beneath. It is a rare plant, 

 growing at an altitude of about 2000 m. 



Montana: Spanish Basin, June 30, 1897, Rydberg <£• Bessey, 

 4379 y 1 8 7 1 , Ro bert A da nis . 



Potentilla flabelliformis Lehm. Stirp. Pug. 2:12 [Rydb. Mon. 74] ; 



Potentilla gracilis Jlabelliformis Torr. &: Gray, Fl. N. Am. i : 



440 [Man. R. M. 85 : Bot. Cal. i : 179]. 



The leaves are divided to near the midrib into linear segments 

 which are white-tomentose beneath and their margins are more or less 

 revolute. The flowers are rather small and the branches of the 

 cyme rather long. In open valleys, at an altitude of 1000-2000 m. 



