Part 4, 1908] ROSACEAE 311 
late; petioles often 2 dm. long, villous with spreading hairs; leaflets 4-7 cm. long, broadly 
oblanceolate in outline, brownish-strigose on both sides, paler beneath, pectinately divided 
to near the midrib; segments linear, obtuse; stem-leaves similar but short-petioled or sub- 
sessile, smaller ; cyme many-flowered, corymbiform ; hypanthium and calyx villous-strigose; 
bractlets linear, obtuse, about half as long as the ovate-lanceolate acute sepals, which are 4-6 
mm. long; petals yellow, 5-6 mm. long, obovate; stamens 20; pistils many; styles filiform. 
TYPE LOCALITY : Spread Creek, in the Teton Forest Reserve, Wyoming. 
DISTRIBUTION : Mountains from Colorado to Montana. 
29. Potentilla Nuttallii Lehm. Stirp. Pug. 9: 44. 1851. 
Potentilla recta Nutt. Gen. 1: 310, 1818. Not P, ‘recta L. 1753. 
Potentilia rigida Nutt. Jour. Acad. Phila. 7: 20. 1834. Not P. rigida Wall. 1828. 
Potentilla chrysantha Lehm. in Hook. Fl. Bor. Am. 1: 193. 1832. Not P. chrysantha Trev. 1818. 
Potentilla gracilis rigida §. Wats. Proc. Am, Acad. 8: 557. 1873. 
Potentilla gracilis chrysantha Rydb. Fl. Neb. 21: 16. 1895. 
Perennial, with a short rootstock ; stem 6-8 dm. high, stout, sparingly hirsute, branched 
above; stipules lanceolate, acute, subentire; basal leaves many, digitate, with about 7 
leaflets, prominently veiny and sparingly hirsute, not at all tomentose beneath, green, 
usually glandular-granuliferous; petioles 1-3 dm. long, pubescent with usually appressed 
hairs; leaflets 5-10 cm. long, oblanceolate, toothed or divided nearly halfway to the midrib, 
with large triangular-divergent, acute teeth; stem-leaves smaller and short-petioled ; cyme 
many-flowered; hypanthium hirsute, in fruit about 1 cm. in diameter; bractlets linear 
to lanceolate, generally shorter than the ovate-lanceolate, long-acuminate sepals, which 
are 5-7 mm. long; petals yellow, obovate, emarginate, 6-8 mm. long; stamens 20; pistils 
many; styles filiform. 
TYPE LOCALITY: Fort Mandan [Dakota]. : 
DISTRIBUTION.: Mountain valleys from Saskatchewan to British Columbia, Colorado, and 
Oregon. . 
ILLUSTRATIONS: Lehim. Rev. Potent. p/. 37; Mem. Dep. Bot. Columbia Univ. 2: pi. 26. 
30. Potentilla Townsendii Rydb. Bull. Torrey Club 28: 174. 1901. 
? Potentilla nervata M. E. Jones, Contr. West. Bot. 12: 15. 1908. 
A slender perennial with a deep root, and a short caudex covered by the brown remains 
of old leaves ; stem ascending, 3-5 dm. high, sparingly silky ; petioles of the digitate basal 
leaves 7-10 mm. long, slightly appressed-hairy ; stipules adnate to the petioles, the free 
portion linear-subulate; leaflets 5-7, oblanceolate to almost linear, serrate, acute, glabrous 
above, sparingly hairy beneath, principally on the veins; stem-leaves 2 or 3, similar, but with 
shorter petioles; stipules large, 3-4 cm. long, lanceolate or ovate-lanceolate ; cyme rather 
open; hypanthium and calyx silky-strigose ; bractlets linear-lanceolate, 6-8 mm. long, 
equaling the lanceolate sepals ; petals yellow, broadly obcordate, about lcm. long; stamens 
about 20; pistils many; styles filiform. 
TyPE LOCALITY: Sierra Madre, near Colonia Garcia, Chihuahua, Mexico. 
DISTRIBUTION : Sierra Madre, Chihuahua. 
31. Potentilla angustata Rydberg, sp. nov. 
Perennial, with a short rootstock and caudex ; stem slender, strict, about 8 dm. high, 
usually with ascending hairs; basal leaves digitately 5-7-foliolate ; petioles 1-1.5 dm. long, 
pubescent, with appressed or slightly spreading hairs; leaflets narrowly oblanceolate, rather 
copiously hairy on both sides but green ; the middle one 4-6 cm. long ; the outer, especi- 
ally if the leaves are 7-foliolate, small, 1-2 cm. long, cut-toothed with lanceolate teeth ; 
lower stem-leaves similar, the upper 3-foliolate and subsessile; inflorescence few-flowered, 
with slender branches; hypanthium silky, in fruit 6 mm. wide ; bractlets linear-lanceolate, 
about 3 mm. long; sepals ovate-lanceolate, 5-6 mm. long, acuminate; petals 6-7 mm. 
long, obovate, retuse; stamens about 20; pistils many ; styles filiform. 
Type collected on the Upper Sacramento River, California, 1894, #. HY. Foster (herb. N. Y. 
Bot. Gard.). 
