l86 MEMOIRS OF THE NEW YORK BOTANICAL GARDEN. 



Rather common in rich soil, up to an ahitude of 2500 m. 



Montana: Spanish Basin, July i, 1897, J^ydbcrg & Bcsscy^ 

 4.20 J ; Bridger Mts., June 11-17, 42oy-42og; Spanish Basin, June 30, 

 4204; Bozeman, 1882, Tweedy, ijj, in part; 1887,^0 (a form with 

 broad leaves and angled pod, similar to I^vdbe?'g ct- Bcsscy, 4.20J) ; 

 Belt Mts., 1885, F. W. Anderson; Electric Peak, Aug. 20, 1897, 

 Rydherg & Besscy, 42GJ (?); West Gallatin, 1883, Seribner, Sh; 

 Jefferson City, 8e. 



Yellowstone Park: Mammoth Hot Springs, 1885, J^. Tzcecdy^ 

 SjS; 1884, 200 (similar to jo). 



* Arabis furcataWats. Proc. Am. Acad. 17 : 362 [Syn. Fl. i^ : 161] . 



A low perennial, somewhat resembling A. ^^iittallii, but glabrous, 

 with larger flowers, and rather thick and shining basal leaves. 

 Rather common in exposed situations on the mountains, at an altitude 

 of 2500-3500 m. 



Montana: Bozeman, id>(^^, Rxdbe7'g, 26"/^ ; Bridger Mts., 1896, 

 Flodman, jOj ; Bridger Mts., June 15, 1897, Rydberg & Besscy y 

 42J0; Lone Mt., 1886, Tweedy, 1084; Middle Creek, 1887, ^7. 



Idaho : Mt. Chauvet, July 29, 1897, Rydberg & Bessey, 4228^. 



Arabis hirsuta Scop. Fl. Carn. Ed. 2, 2 : 30 [Syn. Fl. i' : 162; 



Man. R. M. 9; 111. Fl. 2: 149; Bot. Cal. i : 32]. 



In valleys, on river banks, etc., up to an altitude of 2500 m. 



Montana: Jack Creek, July 16, 1897, Rydberg d- Bessey, 421 1 ; 

 Helena, 1887, Kelsey. 



Yellowstone Park: Gardiner, 1885, Tzceedy, jjj ; ]Mammoth 

 Hot Springs, ^j^- 



Arabis Holboellii Hornem. Fl. Dan. 11 : pi. iSyg [Syn. Fl. i' : 164 ; 



Man. R. M. 164; 111. Fl. 2: 150; Bot. Cal. i: 33]. 



Dry hills, at an altitude of 1000-2000 m. 



Montana: Pony, July 6-8, 1897, Rydberg d- Bessey, 422/ and 

 4228; Bridger JNIts., June 18,4224; Bozeman, 1882, Tzveedy i Great 

 Falls, 1888, R. S. WiHianis; West Gallatin, 1883, Seribner, 8c. 



*Arabis Bourgovii ; Ttirritis patula Grab. Edinb. New Phil. Journ. 



1829 : 350. 1829 ; Arabis Holboellii (j^ fatiila Wats. ; Gra3% Syn. 



Fl. i^ : 164. 1895: not yl. ^«/«/rt Weinm. 1810. 



More slender than the preceding and almost glabrous, with pods 

 broader and less reflexed. Hillsides, at an altitude of 2000 m. 



Montana: Jack Creek, July 14, 1897, Rydberg d Bessey, 4222. ■ 



