ROSACEA, (rosk family.) 163 



pnherulent and teeth serrulate ; flowcM lin'ffc, solitary (very rarely 2 or .'^); outer 

 sc'iKiLs usually with 1 or 2 nurrow latenil lohcs, not hispid. — N. Mich, and 

 Wisf. to Minn, and Col. 



5. R. Arkansana, Torter. Stems low, vcri/ jirirklij ; stipules narrow, 

 more or less i^landular-toothed above (or eveu gland ular-ci Hate) ; Uajlets 7-11, 

 broadly elliptical to oblong-oblanceolate, suhruneate at base, sessile or jMjtiolulate, 

 simply toothed, not resinous ; flowers corymbose ; sepals rarely hispid, the outer 

 lobed. — Miuu. to Mo. and W. Tex., west to Col. 



•♦- -t- •♦- Fruit (jlolH)se ; infrastipular spines present. 



6. R. Woodsii, Lindl. Stems usually low (i-3° high), with slender 

 straiglit or recurved s|jines, sometimes with scattered prickles, or wholly un- 

 armed above ; leaflets 5-7, obovate to oblong or lanceolate, more or less toothed ; 

 flowers corymbose or solitary ; scj)als naked or hispid, the outer usually lolnid ; 

 fruit globose with a short neck. — Minn, to Mo., west to Col. 



* * * Styles distinct ; sepals spreading after powering and deciduous ; infra- 

 stipular spines usually present, often with scattered prickles ; sepals, globose 

 receptacle, and pedicel usually hispid ; teeth simple ; pubescence not resinous. 



■i- Leaflets mostly finely many-toothed. 



7. R. Carolina, L. Stems usually tall (1 -7° high), with stout straight 

 or usually more or less curved s])ines ; stipules long and very narrow ; leaflets 

 dull green, 5-9 (usually 7), usually narrowly oblong and acute at each end 

 and petiolulate, but often broader, usualh' pubescent l)eneath. — Borders of 

 swamps and streams, N. Scotia to Fla., west to Minn, and Miss. 



-»- -f- Leaflets coarsely toothed. 



8. R. Iticida, Ehrh. Stems often tall and stout (a few inches to 6° high), 



with at length stout and usually more or less hooked spines ; stipules usually 

 naked, more or less dilated ; leaflets (mostly 7) dark green, rather thick, smooth 

 and often shining above ; flowers corymbose or Sf^litary ; outer sepals freijuently 

 with 1 or 2 small lobes. — Margins of swamj)s <n- moist ])laces, Newf. to 

 N. Eng., N. Y., and E. Penn. 



9. R. humilis, Marsh. Stems usually low (1-.'^°) and more slender, 

 less leafy, with straight slender sjiities, spreading or sometimes reflcxcd ; sti- 

 pules narrow, rarely somewhat dilated ; leaflets as in the hist, but usually thin- 

 ner and paler ; flowers very often solitary ; outer sepals always more or less 

 lobed. (K. lucida of most authors.) — Mostly in dry soil or on rocky slopes, 

 Maine to Ga., west to Minn., Mo., Ind. Terr., and La. 



10. R. nitida, Willd. Low, nearly or quite glabrous throughout, the straight 

 slender spines often scarcely stouter than the prickles whirh usually thickly cover 

 the stem and branches; stipides mostly dilated; leaflets bright green and shin- 

 ing, usually narrowly oblong and acute at each end ; flowers solitary (rarely 2 

 or 3) ; sepals entire. — Margins of swamps, Newf. to N. Eng. 



Naturalized speeies. 



R. canIna, L. (Doo Kosk.) Stems armed with stout recurved spines, 

 without prickles, the branches sometimes unarmed; leaflets 5-7, elliptical «)r 

 oblong-ovate, glabrous or .somewhat pubescent, simply toothed, not rcsinou.s- 

 puberuleut; flowers solitary (or 2-4) on usually naked pedicels; .sepals pin- 



