Part 4, 1908] ROSACEAE 331 
102. Potentilla modesta Rydberg, sp. nov. 
Perennial, with a short rootstock ; stems ascending, about 1 dm. high, several-flowered ; 
basal leaves digitately 5-foliolate; petioles 1-4 cm. long, densely villous: leaflets broadly 
obovate, 1-1.5 cm. long, silky but green above, white-tomentose beneath, deeply cleft into 
oblong or lanceolate divisions ; lower stem-leaves similar, the upper subsessile and 1-3- 
foliolate ; inflorescence several-flowered, rather dense, the pedicels short ; stipules lanceo- 
late, about 0.5 em. long; hypanthium hirsute-villous, somewhat glandular-puberulent in 
fruit, 4-5 mm. wide; bractlets linear, about 2 mm. long; sepals lance-ovate, acute, 3 mm. 
long; petals 3-4 mm. long, obcordate ; stamens 20; pistils many; styles filiform. 
Type collected on Mount Barette, near Marysvale, Utah, in 1905, Rydberg & Carlton 7261 (herb. 
N. Y. Bot. Gard.). 
DISTRIBUTION : High mountains of Utah. 
XXII. Niveae. Plants mostly low and tufted. Rootstock often thick, scaly. Ieaves 
digitately 3-foliolate, more or less tomentose beneath. Petals obcordate, yellow. Styles 
short, often inclined to be thickened and glandular at the base. The relationship of the 
group is with ConcINNAH, MULTIFIDAE, and FRIGIDAE. 
103. Potentilla Pringlei S. Wats. Proc. Am. Acad. 23: 272. 1888. 
Stem decumbent, 3 dm. long or more, finely tomentose, as well as the paniculate in- 
florescence ; leaves mostly radical, ternately digitate; leaflets lanceolate, 3-5 cm. long and 
4 mm. broad, acutely toothed, nearly glabrous above, densely white-tomentose beneath ; 
flowers on very slender pedicels, rather large, yellow; calyx-lobes lanceolate; bractlets 
linear; stamens 20; styles filiform, nearly terminal. 
TYPE LOCALITY: Pine plains near Sierra Madre, Chihuahua, Mexico. 
DISTRIBUTION : Known only from the type locality. 
104. Potentilla prostrata Rottb. Skr. Kjob. Selsk. Laerd. & Vidensk. 
10: 453. 1770. 
Potentilia nivea prostrata Lehm. Monog. Potent. 184. 1820. 
Perennial; stem ascending or prostrate, about 2 dm. long, more or less compressed, 
sparingly villous; petioles of the basal leaves 4-5 cm. long, those of the lower stem-leaves 
2 cm. long, villous; stipules lanceolate, about 2 cm. long; leaflets 3, obovate-oblanceolate, 
2.5-3.5 cm. long, deeply cleft more than halfway to the midrib with oblong-lanceolate 
revolute-margined divisions, glabrous and strongly veined above, villous-tomentose but not 
very white beneath; upper stem-leaves unifoliolate, about 3.5 cm. long, lanceolate, few- 
toothed # cyme conglomerate; hypanthium villous; sepals lanceolate, 7-8 mm. long, acute, 
a little longer than the similar bractlets; petals obcordate, about 7 mm. long. 
TYPE LocaLity: Greenland. . 
1 DISTRIBUTION: Known only from the type locality. 
105: Potentilla Hookeriana Lehm. Delect. Sem. Hort. 
Hamb. 1849: 10. 1849. 
Perennial ; stems several from the caudex, 1-2 dm. high, white-tomentose and silky- 
villous, ascending, few-leaved ; stipules lanceolate, acute; leaves with petioles 1-2 cm. long, 
ternate or occasionally with a pair of small extra leaflets, white on both sides, silky-villous 
above, densely tomentose beneath ; leaflets obovate in outline, 1-2cm. long, deeply cleft to 
near the midrib into oblong lobes; middle leaflet short-petioled; flowers in small dense 
cymes, about 8-10 mm. in diameter; hypanthium densely silky-villous, in fruit 5 mm. in 
diameter ; bractlets linear, about equaling the lanceolate, acute sepals; petals obcordate, 
generally a little exceeding the sepals; stamens 20; pistils numerous; styles short, a little 
thickened and: glandular at the base. 
TYPE LOCALITY: North Reales Mictauua reads 
DISTRIBUTION : Saskatchewan to erta an ontana. . . 
ILLUSTRATIONS : Lehm. Rev. Potent. i. 55; Mem. Dep. Bot. Columbia Univ. 2: p/. 33, f. 1-5. 
