ROSACEAE (ROSE FAMILY) 257 



hirsute, its sepals equaling the bracts and the light yellow obovate petals: 

 stamens 15-20: achenes numerous, somewhat rugulose when mature. P. 

 norvegica. Across the continent to the northward and south in the Rocky 

 Mountains to New Mexico. 



7. PotentillaconcinnaRich.Frankl. Ist.Journ. 739. 1823. Stems depressed- 

 spreading, somewhat tomentose: leaves densely white-tomentose beneath, 

 greenish but somewhat silky-villous above, 5-foliolate; leaflets obovate-cune- 

 ate, incisely toothed, 1-3 cm. long; stipules ovate-acuminate: flowers solitary, 

 axillary or radical : sepals silky-villous or tomentose, longer than the bractlets 

 but surpassed by the obcordate petals : carpels 1 5-20. P. humifusa. Through- 

 out our range and to the northwest. 



8. Potentilla bicrenata Rydb. Bull. Torr. Bot. Club 23: 431. 1896. Much 

 like the preceding, the stem short, with spreading branches: leaves greenish 

 but silky above, densely white-tomentose beneath, digitately 5-foliolate; leaf- 

 lets oblong-cuneate, entire except at the truncately 3-5-toothed apex; stipules 

 as in the preceding: calyx silky; its sepals ovate-lanceolate; the bractlets 

 similar but smaller, exceeded by the ovate truncate petals. Wyoming to 

 New Mexico. 



9. Potentilla glomerata A. Nels. Bull. Torr. Bot. Club 26: 480. 1899. 

 Stem stout, simple, erect, 4-8 dm. high, sometimes several from the large 



'woody root: leaves pinnately 5-7-foliolate; the lower long-petioled ; the upper- 

 most reduced and nearly sessile; leaflets oblong to narrowly obovate, cleft 

 into long, oblong, mostly obtuse teeth, green but finely pubescent above, 

 densely white-silky below; stipules oblong-ovate, entire or incised: flowers 

 congested-glomerulate: calyx silky; bractlets oblong, acute, shorter than the 

 sepals which equal the nearly orbicular petals. Western Wyoming, Utah, and 

 Idaho. 



10. Potentilla viridescens Rydb. Monog. Pot. 1. c. 69. Stems erect, branched 

 above, 4-7 dm. high: leaves about 7-foliolate, green but silky above, silky- 

 tomentulose but not white beneath; the lower long petioled; leaflets deeply 

 toothed, the teeth oblong; stipules ovate, incisely cleft: flowers in an open 

 cyme, widely branched, corymbosely broad-topped: calyx and bractlets 

 silky, lanceolate, acuminate, scarcely shorter than the obcordate petals. 

 (P. Bakeri Rydb. Bull. Torr. Bot. Club 31: 560. 1904.) Colorado to Canada. 



11. Potentilla diversifolia Lehm. Stirp. Pug. 2: 9. 1830. Stems erect, 

 often more than one from the crown, branched above, about 2 dm. high: 

 leaves 5-7-foliolate; the lower often approximately pinnate rather than digi- 

 tate; the upper reduced and sometimes trifoliolate; leaflets incisely toothed, 

 silvery silky-hirsute below, green but somewhat hirsute above; stipules 

 lance- or ovate-acuminate : cyme open, several-flowered: sepals softly hirsute, 

 lanceolate, longer than the similar bractlets but well exceeded by the obcor- 

 date petals. P. dissecta. [P. dissecta Pursh, Fl. Am. Sept. 355. 1814 (?).] 

 Infrequent; Colorado to California and north to the British boundary. 



12. Potentilla decurrens (Wats.) Rydb. Bull. Torr. Bot. Club 23: 396. 

 1896. Low and somewhat tufted, about 1 dm. high: leaves subpinnate, 

 5-foliolate, thick, with prominent veins beneath, sparsely villous and somewhat 

 glaucous; leaflets obovate, incisely cleft and more or less decurrent, the lower 

 pair reduced in size; stipules ovate, acute: cyme small, terminal on the scape- 

 like stems, very few-flowered: sepals silky-villous, lance-ovate, exceeding 

 the short obtuse bractlets by as much as they are exceeded by the obcordate 

 petals. Subalpine; northern Wyoming, westward and northward. 



13. Potentilla glaucophylla Lehm. Del. Sem. Hort. Bot. Hamb. 1836: 7. 

 Stems usually several, from a simple or branched scaly caudex, assurgent, 

 1-3 dm. high: leaves digitately 5-foliolate, nearly glabrous on both sides, 

 glaucous-green; leaflets silky on the margin, somewhat unequally serrate; 

 stipules ovate, acuminate, somewhat scarious on the margins: cyme open, 

 several-flowered: bractlets small, about half as long as the lance-ovate merely 

 pubescent sepals: petals broadly obovate, truncate or scarcely retuse at apex. 

 P. dissecta glaucophylla. Very common in moist grassy valleys in the moun- 

 tains; throughout our range. 



ROCKY MT. BOT. 17 



