166 CRUCIFER.^. Arabis. 



1 to 3 lines long ; valves 1-nerved to the middle : seeds small, orbicular, winged, in 2 rows. — 

 Nutt. in Torr. & Gray, Fl. i. 83. A. puberula, Nutt. 1. c. 82; Hook. Ic. t. 359.1— "Rocky 

 Mountains," and Blue Mountains, Oregon, Nutlall ; Camp Harney, Oregon, T. Howell; near 

 Mt. Adams, Washington, Stiksdorf. 



++ ++ Pubescence stellately branched, scanty or wanting. 

 A. suflfrutescens, Watson. Perennial, usually glabrous throughout : stems several from 

 a branching woody caudex, glabrous, a foot high : leaves glabrous or sometimes sparingly 

 stellate-pubescent, narrowly oblanceolate ; the cauline narrowly lanceolate, scarcely auricu- 

 late : flowers few, 3 lines long, purplish : pods pendulous on pedicels 4 to 6 lines long, 1| to 

 2^ inches Ion"' by as many lines broad, more or less attenuate to a short thick style ; valves 

 1-nerved, veined ; seeds in 2 rows, orbicular, winged. — Proc. Am. Acad. xvii. 362. — Bluffs 

 of Snake River, E. Oregon, Cusick; Mt. Adams, Washington, Suksdorf, Howell; Siskiyou 

 Mountains, S. Oregon, Howell. 



^— H— -1— Pods ascending, rarely widely spreading. 

 ++ Glaucous, hoary below with fine and dense stellate pubescence. 



A. Lemmoni, Watson. Perennial, low (6 inches high or less) : stems several from a 

 branching caudex, slender, glabrous above : lower leaves spatulate-oblauceolate, rarely with 



1 or 2 teeth, 6 to 9 lines long ; the petiole sometimes ciliate ; the cauline leaves oblong- 

 lanceolate, mostly glabrous or nearly so : flowers 2 to 3 lines long, rose-colored : the sepals 

 pubescent : pods ascending or widely spreading, somewhat arcuate, 1 to If inches long by 

 two thirds line wide, on usually short pedicels (1 to 3 lines long), glabrous, more or less 

 attenuate above to a sessile stigma or short style; valves 1-nerved to the middle or nearly 

 nerveless: seeds in one row, orbicular, narrowly winged. — Proc. Am. Acad. xxii. 467. 

 A. canescens, & var. latifolia, Wats. Bot. King Exp. 17. A. canescens, Brew. & Wats. Bot. 

 Calif, i. 32. A. canescens, & var. (?) stylosa, Wats. ibid. ii. 431. — In the moimtains of 

 W. Wyoming, Parry, and Montana, Richardson, Watson, Canby, to Brit. America at Bow 

 River Pass and Silver City, Mucoun, westward to Mt. Adams, Wash., Suksdorf, and south- 

 ward to.N. California, Lemmon, Mrs. Austin, and N. Nevada, Watson. 



++ ++ Pubescence stellate, scanty or wanting : green or scarcely glaucous. 



A. Drunnnondii, Gray. Biennial (or rarely perennial), slightly glaucous : stems erect, 

 one or several, a foot or two high: radical leaves narrowly oblanceolate, more or less 

 pubescent with malpighiaceous hairs (attached by the middle and usually longitudinally 

 appressed) ; the cauline leaves oblong to linear-lanceolate, 1 to 2 inches in length : petals 

 white or pinkish, 3 to 4 lines long, twice longer tlian the narrow sepals : pods erect when 

 mature, 1 to \\ lines broad, 1| to 3 inches long, obtuse; the stigma sessile or nearly so; 

 valves 1-nerved, veined ; seeds broadly elliptical, winged, two thirds line wide. — Proc. Am. 

 Acad. vi. 187. 1 A. Breutelii, Lange, Medd. Green, iii. 81 (only once collected and without 

 fruit). Turritis stricta. Grab. Edinb. New Phil. Jour. 1829, 3.50. Streptanihus angusti- 

 folius, Nutt. in Torr. & Gray, Fl. i. 76. — Rocky Mountains from Brit. America to N. Utah ; 

 Cypress Hills, Canada, Macoun; E. Humboldt Mts., Nevada, Watson; Mono Pass, Calif., 

 Brewer, no. 1729. 



A. Lyallii, Watson. Perennial, low (rarely a foot high), glabrous throughout or some- 

 times more or less stellate-pubescent below : stems several or many from a branched caudex : 

 lower leaves spatulate to linear-oblanceolate, usually one half to one inch long, sometimes 



2 to 3 inches long; the cauline narrowly lanceolate to oblong, sometimes scarcely auricled : 

 flowers rose-color, 2 to 3 lines long : sepals glabrous : pods erect or ascending, straight or 

 nearly so, 1 to 2 inches long by two thirds to one line broad, narrowed to a short style or 

 sessile stigma; valves 1-nerved, at least to the middle, veined : seeds orbicular, narrowly 

 winged, usually in 1 row. — Proc. Am. Acad. xi. 122. A. Dnimmondii, & var. alpina, 

 Wats. Bot. King Exp. 17, in part. — Frequent in the mountains, often alpine or subalpine, 

 from Brit. America, Lyall, Macoun ; W. Montana, Canhy, and N. Utah, Jones, to the Sierra 

 Nevada, Mono Co., Calif., Brewer, Shockley, and the Cascade Mts. of Oregon and Washington. 



1 Add syn. A. pnuciflortm, Nutt. in herb. (Pliilad. Acad. Sci.), which is with .scarcely a doubt 

 Nuttall's sisymbrium pa uciflorim, described in Torr. & Gray, Fl. i. 93 (notwithstanding the character 

 "not canesceut "), a species otherwise wholly obscure. 



