332 NORTH AMERICAN FLORA [VoLuME 22 
106. Potentilla Pedersenii Rydberg, sp. nov. 
Potentilla subquinata Pedersentt Rydb. Bull. Torrey Club 28: 182. 1901. 
Caudex with elongate branches covered by the remains of old leaves; stems low, less 
than 1 dm. high, 1-3-flowered, covered, as well as the petioles, with long white hairs ; basal 
leaves 3-5-foliolate; leaflets small, 1-1.5 cm. long, broadly obovate, white-silky on both 
sides and tomentose beneath, in age more glabrate above; stem-leaves small, 3-foliolate; 
hypanthium villous, 5 mm. in diameter in fruit; bractlets very narrow, linear or linear- 
lanceolate; sepals lanceolate, about 5 mm. long; petals obcordate, 5-6 mm. long ; stamens 
about 20; pistils many; styles filiform. 
TYPE LOCALITY: Vaigat Assuk, Disco, Greenland. 
DISTRIBUTION : Island of Disco. 
107. Potentilla nipharga Rydberg, sp. nov. 
Potentilla nivea dissecta S. Wats. Proc. Am. Acad. 8: 559, in part. 1873. 
Potentilla nivea subquinata Lange, Consp. Fl. Groenl. 9, in part. 1880. 
Potentilla nivea arenosa Lange, Consp. Fl. Groenl. 236. 1887. Not. P. nivea avenosa Turcz. 1843. 
ote nivea pinnatifida Lange, Consp. Fl. Groenl. 236. 1887. Not P. nivea pinnatifida Lehm. 
185 
Potentilla nivea altaica Rydb. Mem. Dep. Bot. Columbia Univ. 2: 86. 1898. Not P. aliaica Bunge, 
1830 
Potentilia subquinaia Rydb. Bull. Torrey Club 28: 181, in part. 1901. 
Perennial, with a short caudex ; stem 1-2 dm. high, sparingly villous; leaves ternate 
or the uppermost unifoliolate, some of the basal ones rarely 5-foliolate ; petioles of the 
basal leaves 1-6 cm. long, villous; leaflets obovate to oblanceolate, 1-2.5cm. long, sparingly 
hairy and glabrous above, white-tomentose beneath, the terminal one sometimes petiolulate, 
deeply cleft into lanceolate or lance-oblong divisions; stem-leaves short-petioled ; stipules 
lanceolate; inflorescence open; hypanthium villous, in fruit 4-6 mm. wide; bractlets nar- 
rowly linear, 4-6 mm. long; sepals linear-lanceolate, of about the same length; petals 
obcordate, 5-7 mm. long; stamens about 20; pistils many ; styles filiform. 
Type collected at Fort Good Hope on the Mackenzie River, /..S. Onion (herb. N. Y. Bot. Gard.). 
DISTRIBUTION: Arctic America from the Mackenzie to Greenland, and in the Rockies south 
to Utah. 
108. Potentilla nivea L. Sp. Pl. 499. 1753. 
Fragaria nivea Crantz, Inst.2: 179. 1766. 
Potentilia nivea macrophylla Seringe, in DC. Prodr. 2: 571. 1825. 
Potentilla nivea pallidior Sw. Sunima Veg. Scand. 19. 1814. 
Potentilla nivea subviridis Ledeb. Fl. Ross. 2: 57. 1844. 
Potentilla nivea subquinata Lange, Consp. Fl. Groenl. 9, in part. 1880. 
Cespitose perennial, with the caudex covered with the brown scarious stipules and old 
leaves ; stems several, 1-2 dm. high, more or less tomentose or villous, few-leaved ; basal 
leaves on petioles 2-5 cm. long, ternate, glabrate or slightly villous above, densely white- 
tomentose beneath (less densely so in var. pallidior); leaflets oblong-cuneate or obovate, 
2-3 cm. long or (in var. macrophylla) broadly obovate and 3-6 cm. long, generally coarsely 
crenate; stem-leaves similar but smaller; cyme 2-6-flowered; flowers 12-15 mm. in diam- 
eter; hypanthium 6-8 mm. wide in fruit, white-villous or tomentose; bractlets linear to 
lanceolate, slightly shorter than the lanceolate acute sepals, which are5-6 mm. long; petals 
obcordate, exceeding the sepals, 6-8 mm. long; stamens 20; pistils many; styles filiform. 
TYPE LOCALITY: Lapland [Sweden]. 
DISTRIBUTION : Arctic and alpine regions of the northern hemisphere, in America extending 
from Alaska to Greenland and Quebec, and south in the Rockies to Colorado. 
ILLUSTRATIONS: Fl. Dan. f/, 1035 ; Sturm, Deuts. Fl. 92: 67.6; Gmel. Fl. Sib. 3: p1. 36, f. 
i, Britt. & Brown, Ill. Fl. f 1918 ; Mem. Dep. Bot. Columbia Univ. 2: f/. 34, f. 6-10.—(var. 
macrophylla) Skr. Kj¢b. Selsk. Laerd. & Vidensk. 10: f/.7 ; Bot. Mag. p/. 2982 ; Bot. Cab. pi. 460. 
109. Potentilla uniflora Ledeb. Mém. Acad. St. Petersb. 5: 543. 1812. 
Potentilla macrantha unifiora G. Don, Gen. Hist. 2: 550. 1832. 
Potentilla nivea y T. & G. Fl. N. Am. 1: 441, in part. 1840. 
Potentilia villosa uniflora Ledeb. Fl. Ross. 2: 58. 1844. 
Potentilla nivea Vahliana Seem. Bot. Voy. Herald 29, in part. 1852. 
Potentilla nivea unifiora Rydb, Bull. Torrey Club 23: 303. 1896, 
Densely cespitose perennial, the caudex covered with the dark-brown scarious stipules 
and remains of old leaves; stems about 5 cm. high, more slender than in P. Vahkiiana, 
