ParT 6, 1918] ROSACEAE 531 
126. Rosa gymnocarpa Nutt.; T. & G. Fl. N. Am. 1: 461. 1840. 
Rosa spithamea subinermis Engelm. Bot. Gaz. 6: 236. 1881. 
Rosa glaucodermis Greene, Leaflets 2: 255. 1912. 
Rosa abielorum Greene, Leaflets 2: 257. 1912. 
? Rosa amplifolia Greene, Leaflets 2: 258. 1912. 
Stem slender, 1-3 m. high, terete, brown or purplish, often very bristly and with infra- 
stipular prickles, which are very slender, terete, sometimes not larger than the scattered 
bristles, sometimes 1 cm. long; floral branches 1—2 dm. long, prickly or unarmed; stipules 
adnate, 5-15 mm. long, the lower narrow, the upper dilated, glabrous on the back, glandular- 
ciliate and dentate on the margin; rachis and petiole usually more or less glandular-hispid; 
leaflets 5-7 (rarely 9), from suborbicular to elliptic, 1—3.5 cm. long, thin, shining above, dull 
but not pale beneath, glabrous on both sides, doubly-serrate with gland-tipped teeth and 
sometimes glandular on the veins, reticulate with subpellucid veins; flowers usually solitary; 
pedicels 1-3 cm. long, slender, glabrous or more or less glandular-hispid; hypanthium ellipsoid, 
in fruit 4-6 mm. thick, 6-8 mm. long, sometimes becoming almost spherical; sepals ovate, 
acuminate, rarely caudate, 5-8 mm., sometimes 10 mm. long, purplish, glabrous on the back, 
tomentose on the margins and within, deciduous together with the upper part of the hypan- 
thium and the styles; petals 10-15 mm. long, obcordate; styles few, distinct and deciduous. 
TYPE LOCALITY: Oregon, in shady woods. 
DISTRIBUTION: British Columbia to Montana and California. 
ILLUSTRATIONS: Bot. Mex. Bound. pl. 21; Willm. Gen. Rosa pl. opp. 221; Armstrong, Field Book 
W. Wild FI. 223, f. 
Rosa gymnocarpa X Macounii. ‘This has the slender stem and slender prickles of R. gymno- 
carpa, but the leaves are mostly simple-toothed, scarcely glandular-dentate, and slightly puberulent 
and paler beneath; the carpe!s are more numerous; the fruit is larger, about 1 cm. in diameter, the 
styles slightly exserted, and the sepals more persistent. Mac Abee’s Ranch, Priest River Valley, 
Montana, July 23, 1900, MacDougal 80. 
Rosa gymnocarpa X nutkana. This resembles most R. gymnocarpa, but is a more robust 
and taller plant, with somewhat larger petals, more elongate-caudate and apparently persistent 
sepals. ‘The prickles are much larger and stouter and more or less flattened; the young shoots are 
bristly as in R. gymnocarpa; the carpels are much more numerous. Crescent, British Columbia, 
May 30, 1915, J. K. Henry. 
Rosa gymnocarpa X pisocarpa. See under R. pisocarpa. 
Rosa gymnocarpa X pyrifera. This resembles most R. pyrifera in habit and pubescence, the 
leaves being finely puberulent beneath and the inflorescence corymbose. It approaches R. gymno- 
carpa in the broader leaflets, which are more or less double-toothed, in the short, broad, and purple- 
tinged sepals, the few carpels, and exserted styles. The hypanthium has a distinct neck. Big 
Fork, Montana, July 8, 1901, MacDougal 579. 
Rosa gymnocarpa X Woodsii. ‘This resembles R. gymnocarpa in habit, leaf-form, leaf-texture 
and prickles, but the leaves are mostly simp le-toothed and glabrous, the sepals narrowly lanceolate, 
gradually attenuate, 1.5 cm. long and apparently persistent. The carpels are more numerous 
than in R. gymnocarpa, the hypanthium subglobose, and the styles but slightly exserted. Tobacco 
Mountains, Montana, July 14, 1909, B. T. Butler 4238. 
127. Rosa prionota Greene, Leaflets 2: 256. 1912. 
Rosa piscatoria Greene, Leaflets 2: 256. 1912. 
Rosa apiculata Greene, Leaflets 2: 259. 1912. 
Stem 1-2 m. high or more, slender, red or green, glabrous, more or less densely bristly and 
armed with slender, straight infrastipular prickles 5-10 mm. long; bristles and prickles ascend- 
ing or spreading; leaves 7—9-foliolate; stipules short, less than 1 cm. long, rather broad, glan- 
dular-ciliate, the free portion lanceolate or ovate; rachis and petiole strongly glandular-hispid; 
leaflets oval, obtuse at the apex, at least the terminal one acute at the base, doubly glandular- 
serrate, with lanceolate teeth, bright green on both sides, glabrous, glandular only on the 
midrib beneath, usually less than 1 em. long, rarely 1.5 cm. long, reticulate beneath with semi- 
pellucid veinlets; flowers solitary ; pedicels 1-2 cm. long, more or less glandular-hispid; hypan- 
thium glabrous, ellipsoid or in fruit often becoming subglobose, often more or less apiculate (R. 
apiculata), 4-5 mm. in diameter; sepals ovate, caudate, acuminate, 1 cm. long or less, glabrous 
on the back, tomentose within and on the margins, rarely with a few scattered glands along 
the margins (R. piscatoria), in age deciduous together with the upper part of the hypanthium; 
achenes few and large; styles distinct, deciduous. 
TYPE LOCALITY: Lake County, California. ; , 
DISTRIBUTION: Vancouver Island to Central California. 
