264 ROSACEAE (ROSE FAMILY) 



Calyx-tube and fruit not prickly. 



Sepals connivent and persistent after flowering. 

 Infrastipular spines wanting. 



Flowers solitary; sepals erect . . . . . . . 1. R. Sayi. 



Flowers corymbed; sepals spreading. 2. R. arkansana. 



Infrastipular spines commonly present. 



Rachis of leaves more or less prickly 3. R. Fendleri. 



Rachis of leaves without prickles. 



Outer sepals laterally lobed . 4. R. Woodsii. 



Outer sepals entire . . . . . . . . 5. R. Nutkana. 



Sepals spreading after flowering and deciduous . ' . . . 6. R. gymnocarpa. 

 Calyx-tube and fruit prickly. 



Pubescence on young stems lepidote-stellate 7. R. stellata. 



Pubescence wanting, or at least not stellate . . . . . 8. R. MacDougalii. 



1. Rosa Sayi Schwein. Long's Expd. Winnep. 2: 388. 1825. Stems usually 

 low, 3-8 dm. high, thickly covered with prickles: stipules usually dilated, 

 glandular-ciliate and resinous; leaflets 3-7 (usually 5 or 7), glabrous or slightly 

 pubescent above, more or less resinous beneath, broadly elliptical to oblong- 

 lanceolate, usually sessile and rounded or subcordate at base, more or less 

 doubly and glandular toothed, the terminal 2-4 dm. long: flowers solitary 

 (very rarely 2 or 3) : outer sepals with one or more very narrow lateral lobes 

 (very rarely all entire), not hispid, or slightly so on the margin: fruit globose 

 with more or less of a neck below the calyx, 8-12 mm. in diameter (S. Wat- 

 son, Proc. Am. Acad. 20: 340). (R. Engelmannii Wats. Gard. & For. 2: 

 376. 1889; following Watson's view that R. acicularis Lindl. is arctic, R. Sayi 

 is used as the available name.) Colorado and northward into British America. 



2. Rosa arkansana Porter, Syn. Fl. Colo. 38. 1874. Stem stout, erect, 

 leafy, 3-4 dm. high, glabrous and glaucous, armed with weak, deciduous, 

 bristly prickles: leaflets 9-11, ovate and oblong-ovate, 2 cm. or more in length, 

 acute or obtuse, glabrous, sharply serrate; midrib and long stipules somewhat 

 prickly and minutely glandular: flowers numerous, terminal, corymbed, on 

 peduncles about 3 cm. long': fruit globose, smooth, glaucous: calyx-segments 

 ovate, reflexed in fruit, with terminal and sometimes lateral appendages, more 

 or less glandular and tomentose-pubescent on the margins: petals broadly 

 obcordate or emarginate, longer than the calyx-segments, rose-color: flowers 

 4-5 cm. in diameter. (R. pratincola Greene, Pitt. 4: 13.^1899; R. manca 

 Greene, 1. c. 11.) From Colorado northward and eastward into the plains of 

 the upper Missouri region. 



3. Rosa Fendleri Crepin, Bull. Soc. Bot. Belg. 15: 91. 1876. Stems often 

 tall (15-20 dm. high, or less), with rather slender, straight or recurved spines, 

 often scattered or wanting: stipules mostly narrow, usually naked, some- 

 times glandular-ciliate; rachis pubescent or prickly; leaflets 5 or 7 (very 

 rarely 9), oblong or obovate, more or less cuneate at base and often petiol- 

 ulate, usually glaucous, very finely pubescent beneath or glabrous or some- 

 what resinous, the teeth usually simple: flowers small, often solitary, the 

 short pedicels, receptacles, and sepals glabrous, or the last subpubescent: 

 fruit globose or broadly ovate, with little or no neck, about 8 mm. broad 

 (Watson, 1. c.). Western Texas, westward to the Sierras and northward in 

 the Rocky Mountains to British America. 



4. Rosa Woodsii Lindl. Mon. Ros. 21. 1820. Stems usually low, 2-10 dm. 

 high, with slender, straight or recurved spines, and sometimes with scattered 

 prickles, or unarmed above: stipules narrow or dilated, entire; leaflets 5 or 

 7 (sometimes 9), obovate to oblong or lanceolate, rounded or acute at the 

 summit, obtuse or usually cuneate at base, glabrous *or subpubescent above, 

 villous or finely pubescent or glabrous beneath (with the rachis and stipules), 

 simply toothed, often only above the middle, sometimes resinous and serrulate- 

 toothed, sometimes glaucous, usually small (the terminal 1-4 cm. long): 

 flowers 4-5 cm. broad, corymbose or very often solitary, on very short, naked 

 pedicels: sepals naked or hispid, the lobes more or less conspicuous: fruit 

 globose with a short neck, 8-10 mm. broad (Watson, 1. c.). (R. Maximil- 

 lianii Nees. PL Maxim. 8. 1841; R. M-acounii Greene, Pitt. 4: 10. 1899.) 

 From the Missouri river to Colorado and north into British America. 



5. Rosa Nutkana Presl. Epimel. Bot. 203. 1849. Stems stout, 3-15 dm. 



