Part 4, 1908] ROSACEAE 341 
leaves several, the petioles about 5 cm. long, leaflets 7-11; stem-leaves usually several, 
short-petioled, 3-7-foliolate; leaflets gradually diminishing downward, white- or grayish- 
silky on both sides and tomentose beneath, obovate or cuneate-oblong, 2-5 cm. long, 
deeply obtusely toothed, venose beneath, if at all only slightly decurrent on the rachis, 
the upper often confluent, margins not revolute; bractlets lanceolate, usually narrower 
than the sepals, but often nearly equaling them in length, acute; sepals ovate-lanceolate, 
5-7 mm. long, acute; petals 6-8 mm. long, a little exceeding the calyx, obovate, retuse ; 
stamens about 20; pistils many; styles filiform. 
TYPE LOCALITY: Sources of the Platte [Colorado]. 
DISTRIBUTION: Plains and hills from Saskatchewan and Alberta to New Mexico and Arizona. 
ILLUSTRATIONS: Hook. Fl. Bor. Am. p/. 64; Britt. & Brown, Ill. Fl. #1927; Mem. Dep. Bot. 
Columbia Univ. 2: p/. 50. 
138. Potentilla argyrea Rydberg, sp. nov. 
Perennial, with a tap-root and short caudex; stems erect or nearly so, white-tomen- 
tose and silky; basal leaves pinnate, with 7-9 leaflets, 6-12 cm. long; petioles 3-6 cm. 
long, white-tomentose; leaflets oblanceolate or oblong-obovate, 1-3 cm. long, white-tomen- 
tose on both sides, coarsely crenate with ovate teeth; stem-leaves similar but smaller and 
the leaflets more crowded; inflorescence dense and contracted ; stipules ovate, acuminate, 
entire, about 1 em. long; hypanthium white silky-villous, in fruit 6 mm. broad; bractlets 
lanceolate, almost equaling the sepals in length; sepals ovate, acute, 4-5 mm. long; petals 
obcordate, 5 mm, long; stamens about 20; pistils many; styles filiform. 
Type collected at Moose Jaw, Assiniboia [Saskatchewan], in 1896, John Macoun 14441 (herb. 
N. Y. Bot. Gard.). 
DISTRIBUTION: Plains of Saskatchewan and North Dakota. 
139. Potentilla propinqua Rydb. Bull. Torrey Club 28: 176. 1901. 
Potentilia diffusa A. Gray, Mem. Am. Acad. II. 4: 41. 1849. Not P. diffusa Willd. 1809. 
Potentilla Hippiana diffusa Lehm, Delect. Sem. Hort. Hamb. 1849: 8. 1849. 
Potentilla Hippiana pulcherrima S. Wats. Proc. Am. Acad. 8: 555, in part. 1873. 
Potentilla Hippiana propingua Rydb. Bull. Torrey Club 24: 3. 1897. 
Perennial, with a tap-root and short caudex; stems decumbent, ascending, or erect, 
finely silky-strigose, 2-5 dm. high; basal leaves pinnate, with 9-11 leaflets, 5-15 cm. 
long ; petioles silky-strigose, 2-8 cm. long; leaflets oblanceolate, 1-6 cm. long, coarsely 
crenate, green and silky above, white-tomentose beneath, the upper two pairs usually more 
or less decurrent on the rachis: stem-leaves reduced, 3-5-foliolate ; stipules ovate or 
lanceolate, 1-2 cm. long; cymes open; hypanthium silky, in fruit about 6 mm. broad ; 
bractlets lanceolate, 4-5 mm. long; sepals ovate-lanceolate, 5-6 mm. long ; petals obcordate, 
6-8 mm. long; stamens about 20; pistils many ; styles filiform. 
Type LocaLity : Along Santa Fé Creek [New Mexico]. 
DISTRIBUTION: Mountain meadows, from the Black Hills of South Dakota and Alberta to New 
Mexico and Arizona. 
140. Potentilla pulcherrima Lehm. Stirp. Pug. 2: 10. 1830. 
Potentilla pennsylvanica pulcherrima T. & G. Fl, N. Am. 1: 438. 1840. 
Potentilla Hippiana pulcherrima §. Wats. Proc, Am. Acad. 8: 555. 1873. 
Perennial, with a tap-root and short caudex; stems erect or ascending, 4-6 dm. high, 
pubescent with ascending hairs ; basal leaves pinnate, with 5-7 approximate leaflets ; petioles 
6-15 cm. long, pubescent with ascending hairs ; leaflets oblanceolate, 2-7 cm. long, crenate, 
green and silky above, densely white-tomentose beneath, the lower two pairs spreading or 
the lowest reflexed, usually very close together ; cyme open and many-flowered ; hypanthium 
silky-hirsute, in fruit 7 mm. broad ; bractlets 4-5 mm. long, lanceolate ; sepals ovate- 
lanceolate, acuminate, 5-7 mm. long ; petals obcordate, 6-8 mm. long; stamens 20; pistils 
many ; styles filiform. . 
Typr LOCALITY: [Not given in the original publication, but supplied in Hooker’s Flora,] 
Rocky Mountains, between 52° and 56°. 
Oe DISTRIBUTION : In the mountains from Saskatchewan and Alberta to Colorado and Utah, but 
TaN LLUSTRATIONS : Lehm. Rev. Potent. p/. 28; Mem. Dep. Bot. Columbia Univ. 2: pi. 22, 
