ROSACEAE (^KOSE FAMILY) 



4bl 



15. POTENTILLA L. Cinquefoil. Five-finger 



Calyx flat, deeply 6-cleft, with as many bractleta at the sinuses, thus appeal. 

 y 10-cleft. Petals 5, usually roundish. Stamens many. Achenes manv co.. 



- many, 



lected in a head on the dry mostly pubescent or liairy receptacle • styles iater;i\ 

 .'>r terminal, deciduous. Eadicle .superior. — Herbs, or rarely shrubs, with com- 

 pound leaves, and solitary or cymose flowers ; their parts rarely in fours (Nam^ 

 a diminutive from potens, powerful, originally applied to F. Anserma, from iXA 

 once reputed medicinal powers.) 



Petals reddish-purple 

 Petals yellow or white b. 

 b. Stems shrubby 

 b. Steins herbaceous c. 



15. 



P. palustris. 

 P.fruticosa. 



11. P. Robbinsiana 



18. P. pumila. 



19. P. ainadenais. 



21. 



P. reptans, 



P. procumben%. 



4. P. paradoxa. 



c. Flowers solitary, on naked peduncles from the axils of the foliage- 

 leaves or on the stolons. 



Leaves pinnate, of numerous leaflets 17 /> AnRPriim 



Leaves palmate, of 8-5 leaflets. P. An>^ertna. 



Tufted alpine plant 



Plants with elongate slender stems. 

 Earliest flower from the node above the first well-developed 



internode 



Earliest flower from the node above the second or third well- 

 developed internode. 

 Stems ascending or procumbent, not repent 

 Stems repent. 

 Leaflets mostly 5, spatulate-oblong, finely crenate-den- 



tate nearly to the base 



Leaflets inostly 8, cuneate-obovate, coarsely incised 



chiefly above the middle 



C. Flowers cymose, or if solitary in the axils of reduced upper 

 leaves d. 

 d. Leaves pinnate. 



Inflorescence glandular-viscid 1. P. arguta. 



Inflorescence not glandular. 

 Leaves white-pubescent above. 

 Pubescence of the leaves lustrous and silky . . .12. P. Ilippiana. 



Pubescence a dull tomentum 13. P. effuna. 



Leaves green or greenish above. 

 Leaves definitely pinnate, the leaflets essentially uniform ; 



cyme very leafy 



Leaves seemingly palmate, the leaflets crowded and the 

 lower ones much smaller than the others. 



Cyme very leafy ; petals minute 



Cyme scarcely leafy ; petals showy .... 



d,. Leaves palmate e. 



e. Petals white ; leaflets toothed only at tip . 

 6. Petals yeflow ; leaflets toothed along the sides /. 

 /. Tufted alpine plant with 1-2-flowered short branches 

 /. Leafy-stemmed plants with cymose flowers g. 

 g. Petioles and lower part of stem hirsute. 



Leaflets 8 ; petals about as long as the calyx-lobes 

 Leaflets 5-7 ; petals much exceeding the calyx-iobes , 

 g. Petioles and stems woolly or tomentulose h. ' 



h. Leaves silvery-white beneath 



h. Leaves green or at most slightly grayish beneath i 

 i. Plants loosely branched, with very leafy diffuse cymes 



Perennial ; petals obcordate 



Annual or biennial ; petals narrowly cuneate. 

 Achenes strongly gibbous on the ventral side . 5. P. NicoUeiii. 

 Achenes not gibbous on the ventral side . . 3. P. rivalU. 

 i. Plants with simple stems and scarcely leafy corymbi- 



form cymes 9. P. KuHaUii. 



I 1. Styles thickened and glandular toward the base ; achenes glabrous, numer- 

 ous; inflorescence cymose. 

 * Style nearly basal ; stamens 25-80 ; perennial glandular-villous herbs, with 

 pinnate leaves, and rather large white or yellow petals. 

 1. P. arguta Pursh. Stems erect, usually stout, .3-10 dm. high, brownish- 

 hairy, clammy above ; leaflets 7-11, oval or ovate, cut-serrate, downy beneath ; 

 cyme strict and rather close ; stamens mostly 30, on a thick glandular disk 

 {Drymocallis Rydb.) — Rocky, gravelly, or alluvial soils, e. Que. to D. C, ano 

 westw. June, July. 



gray's manual — 31 



. n. 



10. 



P. rivalU. 



P. pe7inisylvanica 



P. tridentata. 



P. Robbinsiana. 



P. monspe'iensis. 

 P. recta. 



7. P. argentea. 



8. P. inter7nedia. 



