MUSTARD FAMILY 65 



3303; Sonora Peak, Tuolumne Co., A. L. Grant 397; Mt. Tallac; Desolation Valley, Eldorado 

 Co., Jepson 8173 (pedicels pubescent) ; Tinkers Knob, Placer Co., Sonne; Lassen Peak, Ches- 

 nut 4' Drew; Hot Springs Valley, n. Plumas Co., Jepson 12,288. Siskiyou Co.: Highland Mine 

 Butler 892. ' 



Kefs. — Akabis lemmonti Wats. Proc. Am. Acad. 22:467 (1887), based on plants from the 

 Eocky Mts. to the Sierra Nevada and Cascades; Jepson, Man. 430 (1925). A. austinae Greene- 

 Fedde, Eep. 5:242 (1908), type loc. Little Chico Creek, R. M. Austin. A. polyclada Greene', 

 Lflts. 2:75 (1910), type loc. Farewell Gap, Purpus 1897. A. depauperata Nels. & Ken. Proc. 

 Biol. Soc. Wash. 19:36 (1906), type loc. Mt. Eose, Nev., Kennedy 1167. A. Icennedyi Greene, 

 Lflts. 2: 71 (1910), type loc. Galena Creek, mts. of Washoe Co., Nev., 8000 ft., P. B. Kennedy. 



A. DAViDSONn Greene, Lflts. 2:159 (1911), type loc. North Fork Bishop Creek, Inyo Co., 

 A. Davidson 2728; Davidson, Bull. S. Cal. Acad. 13:43 (1914). Low glabrous perennial; corolla 

 white or pinkish, 3 lines long; pods narrow, sub falcate, 1^ inches long (ex char.). — It is appar- 

 ently near A. lemmonii Wats, but F. J. Smiley (Univ. Cal. Publ. Bot. 9:205) reduces it to 

 varietal rank as A, lyallii var. davidsonii Smiley. He cites under the variety C. M. Wilder's 

 Mt. Elwell plant which we have named A. cognata. 



10. A. breweri Wats. Brewer Rock-cress. Stems many from the much- 

 branched crown of a stout woody root, 2 to 6 inches high ; herbage pubescent, the 

 hairs seldom more than 3-forked; leaves light-colored or whitish, especially be- 

 neath, as if glaucous; blades of the lower leaves broadly spatulate, entire, 3 to 10 

 lines long, the petioles ciliate ; upper leaves with lanceolate to oblong blades sessile 

 by a subcordate base or obtusely auriculate; flowers bright red-purple or nearly 

 white, 3 to 5 lines long, the pedicels and purplish calyx more or less pubescent; pods 

 spreading and arcuate, glabrous, 1^?^ to 2^/2 inches long, 1 line broad; valves 

 1-nerved, veined; seeds orbicular, narrowly winged, in one row or nearly so. 



Rocky summits of mountain peaks, 3800 to 5500 feet : Coast Ranges from Men- 

 docino Co. to Monterey Co. Apr. 



Logs. — Castle Peak to Middle Eel Eivcr, Jepson 13,373; Mt. Hull, Hall 9570; Snow Mt., 

 Lake Co., T. Brandegee ; Pope Valley grade summit (e. of Calistoga), K. Brandegee ; Mt. Diablo, 

 Greene; Mt. Hamilton, Pendleton 888; Loma Prieta, Davy 449; San Antonio trail, Santa Lucia 

 Mts., Jepson 1662. 



Geog. note. — As an indigenous habitant of the central Coast Eange peaks this species is a 

 definite type fairly well characterized. Beyond this range and towards the north, especially in 

 Siskiyou County, it shades, however, into A. lemmonii Wats., from which it becomes not easily 

 distinguishable. The plants of the northern Sierra Nevada are often not typical A. lemmonii 

 Wats., but we are referring them to that species, partially on geographic grounds: for example, 

 a very slender specimen from Desolation Valley (Jepson 8173) is here listed as A. lemmonii 

 Wats., in spite of the fact that it has pubescent pedicels. 



Var. figularis Jepson var. n. Herbage more hairy; pods rather strictly ascending. — (Pubes- 

 centior; siliquae strictiusculo-ascendentes.) — Potter Valley, Mendocino Co., C. A. Purpus (type). 



Eefs. — Arabis breweri Wats. Proc. Am. Acad. 11:123 (1876), type loc. Mt. Diablo, Brewer, 

 Bolander; Jepson, Fl. W. Mid. Cal. 220 (1901), ed. 2, 187 (1911), Man. 431 fig. 418 (1925). 

 A. epilobioides Greene; Fedde, Eep. 5:242 (1908), type loc. Mt. Sanhedrin, Heller. A. poly- 

 trioha Greene, Lflts. 2: 72 (1910), type loc. Yreka, Butler, probably belongs here also. Var. 

 FIGULARIS Jepson, 



11. A. subpinnatifida Wats. Two-way Rock-cress. Stems simple, 1 or few 

 from a biennial or perennial root, 8 to 12 inches high; herbage (especially the 

 leaves) canescent or almost silvery; basal leaves tufted, the blades very narrowly 

 linear or oblong to linear-oblanceolate, entire or rarely sparingly toothed, 4 to 12 

 lines long, on petioles about as long; blades of the cauline leaves lanceolate, un- 

 equally or saliently incised, sometimes merely toothed, or the uppermost entire; 

 petals rose-color or white, 5 to 7 lines long; pods glabrous or pubescent, straight 

 or slightly curved, 2 to 3 (or 5) inches long, 1 to 11/2 lines wide, markedly attenuate 

 to a short style, and pendent upon recurved or spreading puberulent or hairy pedi- 

 cels 2 to 5 lines long ; valves 1-nerved to the middle and veined ; seeds in 1 row, as 

 broad as the partition, winged. 



Mountains and plateau valleys, 3000 to 5000 feet : Siskiyou Co. Southwestern 

 Oregon to northern Nevada. Apr. 



