KOSACE.^. (rose family.) 137 



2. R. OCCidentaliS, L. Glaucous; stem prickly, but otherwise very 

 smooth, beudiog ; leaves 3 - 5-foliolate ; leaflets thiu, ovate, acumiuate, 

 coarsely serrate or sparingly toothed, white-downy beneath; petals white, 

 shorter than the reflexed short-caudate hoary calyx lobes ; fruit black — 

 Borders of woods along the mountains. May. — Stem biennial, 5° - 8° long. 



* * Heads of achenia oval or ohloivj, persistent : receptacle jtiici/. 



3. R. villoSUS, Ait. Tall, shrubl)y ; stem erect or bending, armed, like 

 the petioles aud peduncles, with stout recurved prickles, the brandies and 3 - 7- 

 foliolate leaves soft-hairy or nearly smooth ; leaflets ovate or oblong, doubly 

 serrate ; racemes leafy below, bracted above ; sepals acuminate, nmch sliorter 

 tliau the obovate white petals; fruit large, oblong, black. — Swampy thickets, 

 common. April. — Stem 4° - 10° high. 



4. R. cuneifolius, Pursh. Shrubby, armed with stout prickles ; stem 

 erect ; brauclies aud leaves tomentose ; leaves trifoliolate, with the leaflets 

 cuneate-obovate, unequally serrate towards the summit, tomentose and white 

 beneath ; racemes few-flowered ; ]jetals white ; fruit ovoid, black. — Old fields. 

 April. — Stem 2° -4^ higli- Leaves and fruit smaller than in the preceding. 



5. R. trivialis, Michx. Shrubby, and armed with stout straight or 

 recurved prickles and bristly hairs ; stem prostrate, slender ; leaves 3-5- 

 foliolate, partly persistent; leaflets smooth, oblong-ovate or obovate, acute, 

 sharply serrate; racemes few-flowered, leafy below, mostly longer than the 

 leaves ; flowers large, white ; fruit black. — Dry sandy soil. April. 



6. R. Canadensis, L. Stem shrubby at the base, slender, trailing, the 

 prickles few and scattered ; leaves mostly 3-foliolate ; leaflets smooth, thin, 

 oval or oblong, coarsely and unequally serrate ; racemes few-flowered, leafy ; 

 fruit large, roundish, black. — Dry sterile soil. North Carolina aud Tennessee. 

 May. 



7. R. hispidus, L. Somewhat shrubby, aud armed with weak bristle- 

 like prickles ; stem slender, prostrate ; leaves trifoliolate, persistent ; leaflets 

 obovate, obtuse, coarsely serrate, smooth ; racemes many-flowered, slender, 

 longer than the leaves ; flowers small, white ; fruit of few large and black 

 achenia. (R. obovalis, Michx.) — Cold shady swamps among the mountains. 

 May - June. — Fruit sour. 



15. ROSA, Tourn. Rose. 



Calyx 5-cleft, the urn-shaped tube becoming fleshy in fruit. Petals 5. Sta- 

 mens numerous, inserted with the petals on the throat of the cah'x. Ovaries 

 numerous, hairy, inserted on the thin receptacle that lines the inner surface 

 of the calyx-tube. Styles neai'ly included. Achenia bony. — Prickly shrubs. 

 Leaves unequally pinnate. Stipules united with the petioles. Flowers showy. 



* Styles cohering, exserted. 

 1. R. setigera, Michx. Stem long, reclining, smooth; leaflets 3-5, 

 ovate, acuminate or acute, serrate, shining above ; petioles, peduncles, and 

 calyx glandular ; corymb few-flowered ; petals obcordate ; fruit globose, 

 smooth. — Borders of swamps, chiefly in the upper districts. June. — Stem 

 10°- 15° long. Flowers 2' -3' wide, red. 



