Genus 7. 



ROSE FAMILY. 



8. Potentilla monspeliensis L. Rough Cinque- 

 foil. Barren Strawberry. Fig. 2234. 



Potentilla monspeliensis L. Sp. PI. 499. 1753. 

 Potentilla norvegica L. Sp. PI. 499. 1753. 

 Potentilla liirsiita Michx. Fl. ]3or. Am. i : 302. 1803. 

 P. labradorica Lehni. Del. Sem. Hort. Hanib. 1849: 12. 

 1849. 



Erect, stout, annual or biennial, branched above, 

 hirsutely rough-pubescent, 6'-2J° high. Stipules 

 foliaceous, incised-dentate or sometimes entire ; 

 leaves 3-foliolate, the lower and basal ones petioled, 

 the upper sessile or nearly so; leaflets obovate, green 

 both sides, obtuse at the apex, mostly narrowed at 

 the base, pubescent with spreading hairs, i'-2' long; 

 flowers yellow, terminal, usually rather densely 

 cymose and leaf^'-bracted, 3"-6" broad ; calyx-lobes 

 ovate, acute, pubescent, a little longer than the obo- 

 vate retuse petals and somewhat broader than the 

 bractlets; stamens 15-20; style glandular-thickened 

 below ; achenes glabrous, rugose or smooth. 



In dry soil, Newfoundland and Labrador to South 

 Carolina, Tennessee, Alaska, Kansas, Arizona and Cali- 

 fornia. Also in Mexico, Europe and Asia. Often oc- 

 curs as a weed in cultivated ground ; consists of several 

 races. June-Sept. 



9. Potentilla pentandra Engelm. Five-stamened Cinquefoil. Fig. 2235. 



T. & G. Fl. N. A. 1 : 447. 1840. 

 pentandra S. Wats, Proc. Am, 



P. pentandra Engelm. 

 Potentilla rivalis var. 

 Acad. 8: 553. 1873. 



Similar to the preceding species, erect, hirsute, 

 i°-4° high, simple at the base, much branched above. 

 Stipules lanceolate, somewhat foliaceous, dentate or 

 entire ; basal and lower leaves slender-petioled, 

 3-foliolate, with the lower pair of leaflets parted 

 nearly to the base, so as to appear 4- or 5-foliolate; 

 leaflets oblanceolate or oblong, obtuse at the apex, 

 narrowed or cuneate at the base, incised-dentate, 

 glabrous or sparingly pubescent above, quite pubes- 

 cent beneath, 1-2' long; flowers terminal, in a more 

 or less flat-topped cyme, pale yellow, 2"-4" broad ; 

 calyx-lobes ovate, acute, exceeding the small spatu- 

 late petals, and equalling or slightly shorter than the 

 lanceolate bractlets; stamens 5-8; style thickened 

 below; achenes glabrous. 



In sandy soil, Manitoba to Alberta, Missouri, Ne- 

 braska and Arkansas. June-Sept. 



10. Potentilla argentea L. Silvery or Hoary 

 Cinquefoil. Fig. 2236. 



Potentilla argentea L. Sp. PI. 497. 1753- 



Stems ascending, tufted, branched, slightly woody at 

 the base, 4'-i2' long, white woolly-pubescent. Stipules 

 lanceolate, acuminate ; leaves all but the uppermost 

 petioled, digitately s-foliolate ; leaflets oblanceolate or 

 obovate, obtuse at the apex, cuneate at the base, green 

 and glabrous above, white-tomentose beneath, laciniate 

 or incised and with revolute margins, 6"-i2" long; 

 flowers cymose, terminal, pedicelled, yellow, 2"-4" 

 broad ; calyx-lobes ovate, acutish, a little shorter than 

 the obovate retuse petals; stamens about 20; style fili- 

 form; achenes glabrous. 



In dry soil. Nova Scotia and Ontario to North Dakota, 

 south to Washington, D. C, Indiana and Kansas. Also in 

 Europe and Asia. May-Sept. 



Potentilla collina Wibel, of Europe, collected at Winona, 

 Minn., and Cambridge,. Mass., differs in its more prostrate 

 habit, broader and not revolute leaflets, and larger calyx. 



