Part 4, 1908] ROSACEAE 329 
diameter ; petals broadly obcordate, a little exceeding the sepals; stamens 20; pistils many ; 
styles filiform. 
TYPE LOCALITY : Plains of the Rocky Mountains [probably Wyoming]. 
DISTRIBUTION : Montana and Wyoming to Nevada and Utah. 
ILLUSTRATION : Mem. Dep. Bot. Columbia Univ. 2: p/. 21, f. 1. 
95. Potentilla Hassei Rydberg, sp. nov. 
Perennial, with a cespitose caudex; stems about 2 dm. high, densely strigose, decum- 
bent at the base; basal leaves mostly 5-foliolate; petioles 3-5 cm. long, densely silky-stri- 
gose; leaflets obovate, 1.5-3 cm. long, crenate or cut-toothed with ovate or oblong-ovate 
teeth, green but densely short-pubescent with appressed hairs above, densely appressed- 
silky beneath ; lower stem-leaves similar, the upper 3-foliolate and sessile ; cyme open but 
with short branches; stipules ovate, about 1 cm. long, entire or somewhat toothed ; 
hypanthium silky-hirsute, in fruit 7 mm. broad; bractlets oblong, 3 mm. long; sepals 
lanceolate, about 5 mm. long; petals obcordate, about equaling the sepals; stamens about 
20; pistils many; styles filiform. 
Type collected in Strawberry Valley, San Diego County, California, in 1892, Dr. H. E. Hasse 
5696 (herb. N. Y. Bot. Gard.). , 
96. Potentilla concinnaeformis Rydb. Mem. Dep. Bot. Columbia 
Univ. 2: 54. 1898. 
Perennial, with a tap-root and scaly caudex; stems about 1 dm. high, ascending, 
slightly silky-strigose, subscapose ; lower stipules scarious and brown, those of the small 
stem-leaves ovate; basal leaves numerous, densely silvery-silky on both sides and slightly 
tomentose beneath, digitate, of about 7 leaflets; stem-leaves small, simple or ternate; 
leafiets 1-2 cm. long, oblong-cuneate, crenate except at the base; hypanthium silky-villous, 
in fruit about 5 mm. in diameter; bractlets oblong-lanceolate, about a third shorter than 
the broadly lanceolate sepals, which are about 4 mm. long, acute; petals yellow, obcordate, 
a third longer than the sepals; stamens about 20; pistils many; styles filiform. 
TYPE LOCALITY: Mt. Agassiz, Arizona. 
DISTRIBUTION : Arizona and southern Utah. 
ILLUSTRATION : Mem. Dep. Bot. Columbia Univ. 2: p/. 15, f. 6-10. 
97. Potentilla concinna Richards. in Frankl. Journey 739. 
1823.— Bot. App. Frankl. Journey ed. 2. 20. 1823. 
Potentilla humifusa Nutt. Gen. 1: 310. 1818. Not P. humifusa Willd. 1813. 
Potentilla puichella Spreng. Syst. 4: Cur. Post. 199. 1827. Not P. pulchelia R. Br. 1819. 
Tormentilla humifusa G. Don, Gen, Hist. 2: 562. 1832. 
Potentilla concinna humifusa Vehm., Stirp. Pug. 9: 49. 1851. 
Potentilla concinna humistrata Rydb. Contr. U. S. Nat. Herb. 3: 497, 1896. 
Low and diffuse perennial, with a thick root and short woody caudex; stems many, in 
the typical form usually spreading, more or less tomentose; stipules ovate-lanceolate, 
acuminate; leaves densely white-tomentose beneath, silky and slightly tomentose above 
when young, digitate (sometimes approximately pinnate), of 5 leaflets; leaflets obovate or 
cuneate, more or less deeply toothed with ovate teeth, 1-3 cm. long; hypanthium silky- 
villous and tomentose, in fruit 6-8 mm. in diameter; bractlets oblong, obtuse or mucro- 
nate, 3-4 mm. long; sepals ovate, acute, 4-5 mm. long ; petals obcordate, a little exceeding 
the sepals, about 6 mm. long; stamens about 20; pistils many; styles short, filiform. 
‘TyPE LOCALITY : Wooded region of British America. 
DISTRIBUTION : Dry hills and mountains from Colorado to Saskatchewan and Alberta. 
ILLUSTRATIONS: Hook. Fl. Bor. Am. 1: fi. 67; Lehm. Monog. Potent. Suppl. £/. 7, f. 2; 
Mem, Dep. Bot. Columbia Univ. 2: p/. 14, f. 1-5. 
98. Potentilla oblanceolata Rydb. Mem. Dep. Bot. Columbia 
Univ. 2: 53. 1898. 
Perennial ; stems several from the caudex, decumbent or spreading, about 1 dm. long, 
with few leaves, silky-villous ; basal leaves numerous, digitately 5-foliolate, silky and green 
