RYDBERG : Rocky MouNTAIN FLORA 437 
differs in the shorter pod and pedicels and the smaller flowers. 
From S. pinnata it differs in being nearly glabrous and by the 
shorter pedicels and the erect pods. It grows on gravelly flats, 
sandy plains and rocky hills, at an attitude of 1300-2000 m. 
Wyominc : Wraith Falls, Yellowstone Park, 1899, Avex Nelson 
GElias Nelson 5710 (type in herb. N. Y. Bot. Gard.) ; Green River. 
1895, Aydberg; Fort Steele, 1901, Tweedy 4479 and 4480 (?), 
Uran: Salt Lake City, 1884, Leonard 272. 
Arabis oreophila sp. nov. 
Arabis Drummondii alpina S. Wats. Bot. King’s Expl. 17, in part. 
1871. 
Perennial with a more or less branched caudex; stems 1-2 
dm. high ; basal leaves numerous, broadly oblanceolate or spatu- 
late, stellate-pubescent ; stem-leaves rather few, lanceolate, slight- 
ly auriculate-clasping ; sepals oblong, 3-4 mm. long, margined 
with purplish, obtuse, glabrous ; petals 7-8 mm. long, yellowish- 
white below, upper portion rose or purplish; pedicels 4-10 mm. 
long, erect or ascending; pods glabrous, 3-6 cm. long, slightly 
arcuate, 2 mm. wide, acute, but beak obsolete; seeds in 2-rows, 
winged above and on one side. 
This species is nearest related to A. Lyallii S. Wats., and was 
included therein, but differs in the broader and shorter basal leaves, 
which are decidedly stellate, and in the pod which lacks a distinct 
beak. It grows on the higher mountains at an altitude of 2500- 
3500 m. 
Urau: Divide between Big Cotton-wdod Cafion and Heber 
Valley, 1905, Rydberg & Carlton 6678 (type in herb. N. Y. Bot. 
Garden, flowers and young fruit); Alta, 1879, Jones 1248 (fr.); 
Uintas, 1869, Watson 75 (fl.) 
Wyomine: Union Peak, 1894, A. Nelson 1007 (fl.); upper 
Buffalo Fork, 1899, C. C. Curtis. 
Montana: Old Hollowtop, 1897, Rydberg & Bessey (fl.). 
Nrw York Botanica, GARDEN. 
