418 ROSACEAE 



ceolate in outline, divided to near the midrib into linear acute segments; sepals 

 narrowly lanceolate, about 4 mm. long; petals obovate, slightly retuse, a little 

 exceeding the sepals. Mountains: Colo. Subalp. Jl. 



48. P. saximontana Rydb. Stems ascending or prostrate, generally not 

 much over 1 dm. high, appressed silky-strigose, more or less leafy and branched; 

 leaves pinnate, with 2-3 approximate pairs of leaflets, silky above, more or less 

 white-tomentulose beneath; leaflets 5-20 mm. long, obovate or oblong in out- 

 line, deeply dissected into narrowly oblong segments; cyme rather few-flowered; 

 sepals lanceolate, acute, 4-5 mm. long; petals obcordate, 6-8 mm. long. P. 

 rubricaulis Rydb., not Lehm. P. rubripes Rydb. Alpine regions: Utah — Colo. 

 — Alta. Alp. — Subalp. Je-Au. 



49. P. minutifolia Rydb. Stems about 1 dm. long, slender, 1- or 2-leaved, 

 sparingly silky or nearly glabrous; basal leaves very small, shghtly grayish 

 beneath, pinnate, with two pairs of leaflets, the upper pair and the sessile odd 

 leaflet about 5 mm. long, the lower pair only 2-3 mm.; leaflets obovate, incised, 

 with oval roimded segments; flowers 1 or 2; sepals lanceolate, obtuse or acutish, 

 about 4 mm. long; petals obcordate, about half longer than the sepals. Moun- 

 tains: Colo. Alp. — Mo7U. Jl. 



50. P. filicaulis (Nutt.) Rydb. Stems several from the caudex, erect or 

 ascending, 1 dm. high or less, silky-strigose, few-leaved; basal leaves many, pin- 

 nate, with 2 or 3 pairs of approximate leaflets, or subdigitately 5-7-foliolate, 

 densely silky on both sides and slightly tomentose beneath; leaflets cuneate, 

 1-2 cm. long, coarsely serrate, with ovate teeth; cyme few-flowered; sepals ovate 

 or ovate-lanceolate, acute, 4-5 mm. long; petals obcordate, 5-6 mm. long. P. 

 effusa filicaulis Nutt. Mountains: Colo. — Ida. Mont. Jl. 



51. P. Macounii Rydb. Stems usually more than one from the caudex, 

 ascending, silky-villous, less than 1 dm. high, 1- or 2-leaved; basal leaves many, 

 pinnate, with 3-5 pairs of rather approximate leaflets, silky on both sides and 

 somewhat tomentose beneath; leaflets cuneate, about 1 cm. long, deeply cleft 

 into oblong segments; cyme few-flowered; sepals ovate, 4-5 mm. long; petals 

 obcordate, 5-7 mm. long. Rocky slopes: Alta.^ — Mont. Submont.—Mont. 

 Je-Au. 



52. P. proxima Rydb. Stems less than 1 dm. high, decumbent or ascend- 

 ing, grayish silky-strigose; basal leaves pinnate, with 7 approximate leaflets; 

 leaflets 7-15 mm. long, obovate, serrate, silky on both sides and white-tomentose 

 beneath; sepals lanceolate, 4 mm. long; petals obcordate, 5 mm. long. Moun- 

 tains: Utah — Ariz. Subalp. Jl-Au. 



53. P. coloradensis Rydb. Stems several, rather slender, silky-tomentose, 

 in age glabrate, about 3 dm. high, branched; leaflets 9-13, finely tomentose, or 

 in age more glabrate; leaflets cuneate-oblanceolate, incisely serrate, with tri- 

 angular acute teeth; bractlets hnear-lanceolate; sepals lanceolate acuminate, 

 about 4 mm. long; petals obcordate, scarcely exceeding the sepals; pistils 10-15 

 (rarely 20). Mountains: Colo. — Wyo. Mo7it. Jl-Au. 



54. P. rupincola Ostcrhout. Stems slender, 2-3 dm. high, glabrous except 

 for a few stiff pointed hairs, erect or nearly so; leaflets of the basal leaves 5-7, 

 narrowly cvmeate, 1-1.5 cm. long, sharply serrate above, glabrous, except the 

 ribs and margins, which are slightly ciliate; sepals narrowly lanceolate, acumin- 

 ate, 3-4 mm. long; petals broadly obovate, retuse, about the length of the sepals; 

 pistils about 6. Mountains: n Colo. Submont. — Mont. Jl-Au. 



55. P. effusa Dougl. Stems many, 2-4 dm. high, slightly silky, ascending 

 or diffuse; basal leaves usually interruptedly pinnate, grayish tomentose on both 

 sides; leaflets 5-11, cuncate-oblong or oblanceolate, the upi)cr often confluent^ 

 crenate, with broad usually ovate teeth; sepals lanceolate-acuminate, 4-5 mm. 

 long; petals obovate, retuse, a little longer than the calyx. Plains and hills: 

 Alta.— Sask.— Neb.— N.M. Plain— Mont. Je-Au. 



56. P. lupina Rydb. Stem 3-4 dm. high, nearly erect, densely grayish 

 pubescent with coarse ascending hairs; basal leaves pinnate, with about 7 ap- 

 proximate leaflets; leaflets oblanceolate, 2-5 cm. long, coarsely crenate, densely 



