ROSE FAMILY 419 



grayish pubescent on both sides and tomentulose beneath; bractlets lanceolate, 

 about 3 mm. long; sepals lance-ovate, acuminate, 5-7 mm. long; petals obcor- 

 date, about equalling the sepals. Mountain slopes: Wyo. Submont. Mont. 

 Jl-Au. 



57. P. Hippiana Lehm. Stem erect, 3-5 dm. high, more or less silky- 

 canescent or white with appressed hairs, leafy; basal leaves several; leaflets 7-11, 

 gradually diminishing downward, white- or grayish-silky on both sides and 

 tomentose beneath, obovate or cuneate-oblong, 2-5 cm. long, deeply obtusely 

 toothed, the upper often confluent; sepals ovate-lanceolate, 5-7 mm. long; 

 petals 6-8 mm. long, obovate, retuse. Plains and hills: Alta. Sask. N.M.- 

 Ariz. Plain Mont. Jl-Au. 



58. P. argyrea Rydb. Stems erect or nearly so, white-tomentose and silky; 

 basal leaves pinnate, with 7-9 leaflets; leaflets oblanceolate or oblong-obovate, 

 1-3 cm. long, white-tomentose on both sides, coarsely crenate; sepals ovate, 

 acute, 4-5 mm. long; petals obcordate, 5 mm. long. Plains: Sask. N.D. 

 Plain. Je-Jl. 



59. P. propinqua Rydb. Stems decumbent, ascending, or erect, finely 

 silky-strigose, 2-5 dm. high; basal leaves pinnate, with 9-11 leaflets; 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; sepals ovate-lanceolate, 5-6 mm. long; petals obcordate, 6-8 mm. long. 

 P. diffusa A. Gray, not Willd. P. Hippiana pulcherrima S. Wats., in part. 

 Mountain meadows : Alta. (Black Hills) S.D. N.M. Ariz. Submont. Mont. 

 Je-Au. 



60. P. pulcherrima Lehm. Stems erect or ascending, 4-6 dm. high, pubes- 

 cent with ascending hairs; basal leaves pinnate, with 5-7 approximate leaflets; 

 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; sepals ovate-lanceolate, acuminate, 5-7 mm. long; petals 

 obcordate, 6-8 mm. long. P. Hippiana pulcherrima S. Wats. P. Wardii Greene. 

 Mountains: Alta. Sask. N.M. Utah. Submont. Mont. Je-Au. 



61. P. viridior Rydb. Stems erect or ascending, glabrous or nearly so, 2-3 

 dm. high; basal leaves pinnate, with 5-7 leaflets; leaflets 0.5-3 cm. long, obovate, 

 green and slightly silky above, paler, silky and sparingly tomentulose beneath, 

 deeply serrate, with lanceolate acute teeth; sepals lanceolate, 4-6 mm. long; 

 petals obcordate, 6-8 mm. long. Mountains: Colo. Subalp. Jl-Au. 



62. P. ambigens Greene. Stem stout, 6-7 dm. high, more or less striate, 

 densely silky-villous, with long spreading hairs; basal leaves irregularly pinnate, 

 silky villous beneath, especially on the rachis and the veins, slightly tomentu- 

 lose when young, more glabrate above; leaflets 9-15, obovate-oblong, 3-6 cm. 

 long, coarsely serrate, more or less decurrent on the rachis, the uppermost con- 

 fluent; sepals lanceolate, acute, 6-7 mm. long; petals about 8 mm. long, obcordate, 

 about a fourth longer than the sepals. Mountains: N.M. Wyo. Submont. 

 Jl-Au. 



63. P. plattensis Nutt. Stems 1-2 dm. high, decumbent or spreading; 

 basal leaves many, pinnate; leaflets 9-17, light green in color, appressed-strigose 

 or glabrate, obovate-oblong in outline, deeply pinnatifid, with oblong obtuse 

 to nearly linear, acutish lobes, 5-8 mm. long; flowers in few-flowered, rather 

 open cymes; sepals and bractlets lanceolate, long-acuminate; sepals 3-4 mm. 

 long; petals yellow, obovate, slightly retuse, longer than the sepals. Valleys: 

 N.M. Utah Sask. Submont. Mont. Je-Au. 



64. P. Nelsoniana Rydb. Stems erect or ascending, 1.5-3 dm. high, gla- 

 brous or sparingly strigose; basal leaves pinnate, with 9-15 leaflets, the earlier 

 appressed-pubescent, the rest glabrate; leaflets cuneate, 1-3.5 cm. long, the upper 

 three pinnately cleft, with 5-7 lance-oblong divisions, the rest 2-3 cleft at the 

 apex or some entire; sepals lance-ovate, 4-5 mm. long, acute; petals obovate, 

 emarginate, 5-6 mm. long. P. pinnatisecta A. Nels., not P. diversifolia pinnati- 

 secta S. Wats. Mountains: Wyo. n Utah Colo. Submont. Subalp. Jl-Au. 



