ROSA 139 



prickles about 3 mm. long, the prickles sometimes larger in the vicinity 

 of the nodes but not forming distinct pairs of infrastipular prickles ; leaves 

 with 7-11, mostly 9, leaflets, leaflets broadly obovate or oblanceolate with 

 stalks about 1 mm. long or sessile, thick, sharply and usually simply ser- 

 rate down to the middle or a little below, upper side dull, nearly smooth, 

 lower side scarcely paler, finely woolly pubescent, the midrib and princi- 

 pal veins prominently ridged, tip occasionally rounded but usually broadly 

 or acutely wedge-shaped, base rounded or wedge-shaped, upper leaflets 

 2-4 cm. long, 1.2-2.5 cm. wide, lower leaflets smaller; petiole and rachis 

 with fine woolly pubescence, sometimes intermixed with a few glandular 

 hairs; stipules simple, entire or serrate, rather narrow, the pair of stipules 

 rarely exceeding 8 mm. in width, thick, usually covered beneath with fine 

 woolly pubescence, showing one prominent vein close to the upper side 

 of the auricle, other veins small; flowering shoots borne on the old wood 

 or often arising directly from the underground parts of the stem, flowers 

 solitary or more frequently in dense clusters of 2-10, bracts of the 

 inflorescence lanceolate, acute; pedicel of flower and outside of receptacle 

 smooth, sepals usually simple, more or less broadened at the tip, 2-2.5 

 cm. long, smooth or glandular pubescent on the outside, densely fine 

 woolly pubescent within, petals bright pink, often of a salmon tone, flower 

 4-6 cm. across; calyx persistent in fruit, somewhat spreading; fruit round 

 or somewhat elongated ; achenes stout, light brown, about 5 mm. long : 

 arkansana, Arkansan, the species being originally described from the 

 valley of the Arkansas river in Colorado. 



Prairies, Wisconsin to Manitoba, Montana and Colorado. Through- 

 out the prairie regions of Minnesota. It intergrades with Rosa blanda. 

 intermediate forms are especially common in the region about Minneapolis 

 where prairie and woodland forms are often much intermixed. 



A rose probably of this species occurs in southeastern Minnesota with 

 few spines, fruit narrow and top-shaped, stipules with prominent auricles,, 

 very long sepals (sometimes over 3 cm. long). 



Rosa acicularis L i n d 1 e y 1820 



R. Sayi Schweinitz 1824 



R. Engelmanni S. Watson 1889 



Shrub 3 dm.-l m. high, stems reddish or greenish, thickly beset with 

 slender straight prickles, 3-6 mm. long, those by the nodes often longer 

 and stouter than the others, but scarcely forming definite infrastipular 

 spines; leaves with 5-7 leaflets, leaflets elliptical or ovate, short-stalked 

 (about 1 mm.) or often entirely sessile, thin, rather coarsely serrate, the 



