ROSE FAMILY 441 



Leaflets very thin, scarcely paler beneath, with distinct reticulations. 



29. R. gymnocarpa. 

 Leaflets not very thin, pale and indistinctly reticulate beneath. 



30. R. leucopsis. 



1. R. arkansana Porter. Stem erect, 2-4 dm. high, copiously bristly, 

 mostly simple, killed back to near the root; glabrous or nearly so, glandular- 

 toothed; rachis and petiole glabrous or sparingly pilose, sometimes glandular; 

 leaflets elliptic, 1.5-6 cm. long, glabrous and shining, coarsely and sharply ser- 

 rate; hypanthium subglobose, glabrous, without a neck, in fruit 12-15 mm. b~road; 

 sepals somewhat glandular on the back; petals obcordate, 2-2.5 cm. long. Plains 

 and canons: Colo. Kans. Wis. Minn. Plain Submont. Je-Jl. 



2. R. Lunellii Greene. Stem erect, simple, 1-3 dm. high, densely bristly; 

 sepals 'glabrous or nearly so, sometimes glandular, entire or gland-toothed on the 

 margins; petiole and rachis glabrous or sparingly puberulent, sometimes glandu- 

 lar; leaflets elliptic or oval, serrate, 1-2.5 cm. long, glabrous on both sides or 

 sparingly pubescent on the veins beneath; hypanthium globose, glabrous, in 

 fruit orange-red and 10-12 mm. thick; sepals glandular on the back; petals 

 rarely 2 cm. long, obcordate. Plains and hills: Man. N.D. S.D. Plain 

 Submont. Je-Jl. 



3. R. suffulta Greene. Stem erect, 3-5 dm. high, usually simple, dying 

 back to near the ground, densely bristly, green ; stipules densely and finely pubes- 

 cent, glandular-dentate on the margins; leaflets obovate, 1.5-4 cm. long, light 

 green, finely and rather densely pubescent on both sides or in age glabrate above, 

 densely serrate; rachis and petiole finely pubescent; hypanthium globose, gla- 

 brous or rarely bristly, in fruit about 1 cm. broad; sepals somewhat glandular on 

 the back; petals obcordate, 2-2.5 cm. long. ft. arkansana S. Wats., not Porter. 

 R. pratincola and R. heliophila Greene. Prairies and plains: 111. Tex. N.M. 

 Wyo. Alta. Man. Flam Submont. Je-Au. 



4. R. alcea Greene. Stem low, 1-3 dm. high, terete, densely bristly, even 

 the floral branches; stipules puberulent, and glandular-hispid and even bristly 

 on the back, glandular-ciliate on the margins, rather broad; rachis and petiole 

 puberulent and glandular; leaflets obovate, 1-2 cm. long, serrate above the middle, 

 glabrous above, finely and densely pubescent and strongly veined beneath; 

 hypanthium globose, glandular-bristly; sepals glandular-hispid on the back; 

 petals obcordate, 15 mm. long. Plains: Sask. N.D. Man. Colo. Plain. 



5. R. collaris Rydb. Stem bristly, but not copiously so, yellowish green, 

 about 1 m. high; stipules glandular-dentate, slightly puberulent; petiole and 

 rachis somewhat puberulent and glandular; leaflets mostly 5, oval, coarsely ser- 

 rate, 1-3 cm. long, glabrous above, finely puberulent beneath; hypanthium small, 

 ellipsoid, contracted into a rather long neck, glabrous; sepals 8-10 cm. long, 

 lanceolate, attenuate, with rather short tips, glabrate on the back. River 

 banks: Ida. JL 



6. R. Engelmannii S. Wats. Stem low, 3-5 dm. high, densely bristly, 

 but rarely prickly; stipules rarely pubescent, conspicuously glandular-granu- 

 liferous and glandular-ciliate; petiole and rachis more or less glandular; leaflets 

 5 or 7, oval, 1-3 cm. long, doubly glandular-serrate, shining above, paler beneath; 

 hypanthium decidedly ellipsoid or pear-shaped, in fruit 8-10 mm. thick, and 12- 

 15 mm. long, with a distinct neck; sepals slightly if at all glandular; petals broadly 

 obcordate, about 2.5 cm. long. Woods: Colo. s Mont. N.D. Svbmont- 

 Mont. Je-Jl. 



7. R. acicularis Lindl-. Stem low, about 1 m. high, densely covered with 

 straight bristles or weak prickles; stipules pubescent, more or less glandular- 

 granuliferous and glandular-ciliate; leaflets 3-7, usually 5, elliptic or oval, 1.5-5 

 cm. long, simply and regularly serrate, dull and glabrous above, pale and finely 

 and densely pubescent beneath; hypanthium glabrous, pear-shaped or elliptic, 

 in fruit 1-1.5 cm. broad and 1.5-2 cm. long, usually with a neck; sepals pubescent 

 and more or less glandular on the back ; petals obcordate, 2-2.5 cm. long. Woods : 

 Alaska Wyo. Mich. N.Y. Boreal Mont. Je-Au. 



18* 



