MUSTARD FAMILY 311 



24. Arabis repanda S. Wats. Repand Rock-cress. Fig. 2120. 



Arabis repanda S. Wats. Proc. Amer. Acad. 11: 122. 1876. 



Biennial, pubescent throughout with short mostly stellate hairs, the pubescence longer and 

 simple at the base ; the stems stout, 4-7 dm. high. Leaves narrowly obovate to oblanceolate, 3-10 

 cm. long, sparingly toothed or entire ; the stem leaves narrowed to a winged petiole ; petals white, 

 narrow, 4-6 mm. long, little exceeding the sepals; pedicels rather stout, ascending, 2-4 mm. 

 long; pods recurved-spreading, 6-8 cm. long, 3-3.5 mm. wide; seeds elliptical, broadly winged. 



Open pine forests in gravelly or rocky places, Arid Transition Zone; central Sierra Nevada to the San 

 Jacinto Mountains, California. Type locality: Yosemite Valley. May-July. 



25. Arabis pulchra M. E. Jones. Beautiful Rock-cress. Fig. 2121. 



Arabis pulchra M. E. Jones, S. Wats. Proc. Amer. Acad. 22: 468. 1887. 



Perennial with a branched woody caudex, canescent throughout with a fine stellate 

 pubescence, the stems erect, 3-5 dm. high, leafy. Leaves not rosulate at base, the lower 25-50 mm. 

 long, narrowly oblanceolate. petioled, entire, the upper linear-lanceolate and sessile; sepals 

 pubescent; petals 6-12 mm. long, rose-colored; fruiting pedicels 5-15 mm. long; pods pendent, 

 3-6 cm. long, 3 mm. wide, finely stellate; stigma sessile; valves 1-nerved; seeds small, in 2 

 rows, orbicular, winged. 



Arid rocky or gravelly slopes, Sonoran Zones; western Nevada and the Mojave and Colorado Deserts, 

 southern California. Type locality: Empire City, Nevada. April-June. 



26. Arabis subpinnatifida S. Wats. Klamath Rock-cress. Fig. 2122. 



Arabis subpinnatifida S. Wats. Proc. Amer. Acad. 20: 353. 1885. 



Biennial or perennial, finely stellate-pubescent throughout, the stems usually several, 15-30 

 cm. high, rarely branched. Leaves silvery with a fine very dense stellate pubescence; the basal 

 narrowly oblanceolate, entire or toothed, 25-50 mm. long; stem leaves lanceolate, sagittate at 

 base, entire or unequally toothed; petals rose-colored, 6-12 mm. long; fruiting pedicels re- 

 curved, pubescent, 5-10 mm. long; pods 3-6 cm. long, 2-3 mm. wide, slightly arcuate and 

 pendent, pubescent, attenuate to a short style ; seeds in 1 row, orbicular, very narrowly margined. 



Rocky and gravelly soils, Arid Transition Zone; Siskiyou Mountains of Oregon and California, east to 

 northern Nevada. Type locality: "West Humboldt Mountains, Nevada." June-Aug. 



27. Arabis Beckwithii S. Wats. Beckwith's Rock-cress. Fig. 2123. 



Arabis Beckwithii S. Wats. Proc. Amer. Acad. 22: 467. 1887. 



Arabis subpinnatifida var. Beckwithii Jepson, Man. Fl. PI. Calif. 431. 1925. 



Perennial, the stem solitary or several from the root crown, 2-3 dm. high, whole plant 

 hoary with a fine, dense, stellate pubescence. Basal leaves narrowly oblanceolate, entire; stem 

 leaves linear-lanceolate, sagittate-clasping but often obscurely so; sepals stellate-pubescent; 

 petals 7-8 mm. long, rose-purple; pedicels arcuately recurved; pods mostly reflexed, 5-7 cm. 

 long, 2 mm. wide, more or less stellate-pubescent, or subglabrous in age; stigma sessile or 

 nearly so ; seeds broadly winged. 



Dry plains and hillsides, Arid Transition Zone; Deschutes County, eastern Oregon, to northeastern Cali- 

 fornia and western Nevada. Type locality: Quartz Mountains, Nevada. May-July. 



28. Arabis suffrutescens S. Wats. Woody Rock-cress. Fig. 2124. 



Arabis suffrutescens S. Wats. Proc. Amer. Acad. 17: 362. 1882. 

 Arabis duriuscula Greene, Pittonia 4: 191. 1900. 



Perennial with a cespitose caudex, the stems several, about 3 dm. high, glabrous. Basal 

 leaves narrowly oblanceolate, 20-25 mm. long, glabrous or sparsely stellate-pubescent; stem 

 leaves scarcely auriculate ; flowers few ; petals purplish, 6 mm. long ; fruiting pedicels recurved, 

 8-12 mm. long; pods pendulous, 3-6 cm. long, 3-5 mm. wide, attenuate to a short, thick style; 

 seeds orbicular, winged, in 2 rows. 



Rocky soils, Arid Transition and Boreal Zones; Mount Adams, Washington, and in the Blue Mountains and 

 Siskiyou Mountains, Oregon. Type locality: "Bluffs of the Snake River, Union County, Oregon." May-July. 



29. Arabis glaucovalvula M. E. Jones. Blue-podded Rock-cress. Fig. 2125. 



Arabis glaucovalvula M. E. Jones, Contr. West. Bot. No. 8: 40. 1898. 



Perennial, stellate-canescent, with a cespitose caudex, the stems several, branched above, 2-4 

 dm. high. Basal leaves rather crowded, oblanceolate, petioled, 2.5-5 cm. long; stem leaves few, 

 reduced, linear-lanceolate, sessile; sepals woolly-pubescent with scarious margins; petals purple, 

 8 mm. long; fruiting pedicels recurved, 4-8 mm. long; pods about 3 cm. long, 6 mm. wide, 

 rounded at each end, pendulous, glabrous and glaucous ; style stout ; seeds in 2 rows, orbicular, 

 with broad membranous wings. 



Gravelly places, Arid Transition and Upper Sonoran Zones; desert ranges of the Mojave Desert, from 

 the Panamint to the San Bernardino Mountains, California. Type locality: "Darwin Mesa, Argus Mountains, 

 California." April-June. 



30. Arabis perennans S. Wats. Perennial Rock-cress. Fig. 2126. 



Arabis perennans S. Wats. Proc. Amer. Acad. 22: 467. 1887. 

 Arabis eremophila Greene, Pittonia 4: 194. 1900. 



Perennial, with a branched and somewhat woody caudex, the stems 3-4 dm. high, roughly 



