Part 4, 1908] ROSACEAE 319 
sepals, which are acuminate and 5-8 mm. long; petals rounded-obcordate, 6-8 mm. long; 
stamens 20; pistils many; styles filiform. 
TYPE LOCALITY: Bear River at Evanston, Wyoming. 
DISTRIBUTION : River bottomis, etc., Montana to Washington, California, and Wyoming. 
ILLUSTRATION: Mem. Dep. Bot. Columbia Univ. 2: p/. 25 (as P. Blaschkeana). 
60. Potentilla dichroa Rydberg, sp. nov. 
Perennial, with a short caudex; stems strict, 4-6 dm. high, densely white-strigose, 
often tinged with purple; basal leaves 7-foliolate ; petioles 5-10 cm. long, white-strigose ; 
leaflets oblanceolate, 3-6 cm. long, green and appressed-silky above, white-tomentose and 
silky beneath, cut-toothed nearly halfway tothe midrib into lanceolate teeth; stem-leaves 
similar, but with shorter petioles and the upper 3~-5-foliolate; stipules ovate or lanceolate, 
1-2 cm. long, entire ; inflorescence rather dense, white-silky ; hypanthium densely white- 
silky ; bractlets lanceolate, 3-4 mm. long; sepals ovate, acute, 6 mm. long; petals obcor- 
date, 7-8 mm. long; stamens 20; pistils many; styles filiform. 
Type collected on Old Sentinel, a mountain near Missoula, Moytana, in 1901, D. 7. Mac- 
Dougai 185 (herb. N. Y¥. Bot. Gard.). 
DISTRIBUTION ;: Western Montana to Oregon, Nevada, and Utah. 
61. Potentilla gracilis Dougl.; Hook. Bot. Mag. A/. 2984. 1830. 
Perennial, with a short caudex ; stem 4-7 dm. high, slender, slightly silky-villous, with 
erect or ascending branches ; stipules lanceolate, 1-3 cm. long, entire, or with 1 or 2 teeth ; 
basal leaves digitate with 5-7 leaflets; petioles slender, 1-1.5 dm. long, with spreading 
pubescence ; leaflets 3-6 cm. long, oblanceolate, green and nearly glabrous above, densely 
and finely white-tomentose beneath, divided about halfway to the midrib into lanceolate- 
triangular coarse teeth ; stem-leaves similar but with shorter petioles; cyme rather narrow ; 
hypanthium long-silky, in fruit 8-10 mm. in diameter; corolla 15-20 mm. in diameter ; 
petals obcordate, deeply emarginate, often over 1 cm. long, much exceeding the sepals; 
bractlets lanceolate, a little shorter than the ovate acuminate sepals, which are 6-7 mm. 
long ; stamens about 20; pistils many; styles filiform. 
TYPE LOCALITY: Banks of Columbia River. 
DISTRIBUTION : British Columbia to western Montana and Oregon. _ 
ILLUSTRATIONS : Bot, Mag. f/. 2984 ; Mem. Dep. Bot. Columbia Univ. 2: pl. 24. 
62. Potentilla camporum Rydberg, sp. nov. 
Perennial, with a short caudex ; stem simple, strict, 3-4 dm. high, hirsute with spread- 
ing or reflexed hairs; basal leaves 7-foliolate ; petioles 6-10 cm. long, hirsute; leaflets 
obovate or broadly oblanceolate, 2-5 cm. long, cut-toothed with lanceolate teeth, densely 
hirsute-strigose above, white-tomentose and silky beneath ; stem-leaves smaller, the upper- 
most 3-foliolate; stipules lanceolate, entire; hypanthium hirsute, in fruit 6 mm. wide; 
bractlets lanceolate, 3-4 mm. long ; sepals ovate-lanceolate, 4-5 mm. long; petals obcordate, 
5-6 mm. long; stamens 20; pistils many; styles filiform. 
Type collected in the Black Hills of South Dakota, Miss Prait 93 (herb. Columbia Univ.). 
DISTRIBUTION : Black Hills of South Dakota to Manitoba. 
63. Potentilla filipes Rydb. Bull. Torrey Club 28: 174. 1901. 
Potentilla Hippiana pulcherrima 8. Wats. Proc. Am. Acad, 8: 555, in part. | 1873. 
Potentilia penis Porter & Coulter, Syn. Fl. Colo. 37. 1874. Not P. gracilis Dougl. 1830. 
Potentilla pulcherrima Rydb. Bull. Torrey Club 24: 5, in part. 1897. Not P. pulcherrima Lehm. 
1830. ° 
Perennial, with several stems from the short caudex; stems 3-5 dm. high, slender, 
silky-hirsute or silky-strigose, simple up to the inflorescence, few-leaved; basal leaves 
mostly 7-foliolate, digitate, with hirsute or strigose petioles 5-15 cm. long ; leaflets obovate 
to oblanceolate, obtuse, coarsely crenate, 2-6 cm. long, green and sparingly strigose above, 
white-tomentose beneath; stem-leaves similar, but smaller, usually 5-foliolate, short- 
petioled ; stipules ovate-lanceolate, entire or sometimes toothed ; cyme open ; pedicels very 
slender, as well as the hypanthium and calyx silky-hirsute and more or less viscid-tomen- 
