MUSTARD FAMILY 295 



2; flowering stems pubescent, 4-6 cm. high; racemes becoming about 2.5 cm. long, 4-6-flowered; 

 petals white, 2-2.5 mm. long; pod linear, 10-15 mm. long, straight or twisted. 



Moist places, Boreal Zones; Cascade Mountains, British Columbia and Washington, east to Alberta and 

 Montana. Type locality: McDonald's Peak, Montana. July- Aug. 



9. Draba ruaxes Payson & St. John, Volcano Draba. Fig. 2073. 



Draba ruaxes Payson & St. John, Proc. Biol. Soc. Wash. 43: 117. 1930. 



Cespitose perennial, subterranean branches freely branching. Leaves crowded, broadly ob- 

 lanceolate to suborbicular, 5-7 mm. long, spreading, densely pubescent with simple and forked 

 hairs, sparsely ciliate toward the base; scapes slender, 2-4 cm. high; racemes short, compact, 

 few-flowered; petals yellow, broadly emarginate, 3 mm. long; pedicels stout, 1-2 mm. long; 

 pods ovate-elliptic, 5-6 mm. long, pubescent with simple hairs ; style stout, . 5 mm. long. 



Rocky slopes, Arctic-Alpine Zone; Coast Ranges of British Columbia to Glacier Peak, Cascade Mountains, 

 Washington. Type locality: crevices of disintegrating flaky andesite, north side of Glacier Peak, Snohomish 

 County, Washington. July-Aug. 



10. Draba Cusickii Robinson. Cusick's Draba. Fig. 2074. 



Draba Cusickii Robinson ex O. E. Schulz, Pflanzenreich 4 105 : 105. 1927. 



Cespitose perennial, branches of the caudex slender. Leaves oblong-obovate, pubescent with 

 stipitate 2-forked hairs, ciliate on the margins ; scapes 8-12 cm. long including the lax raceme, 

 minutely stellate; petals yellow, 4.5 mm. long; pods oblong-ellipsoid, compressed, 6-10 mm. long; 

 style slender, about 1 mm. long; seeds wingless. 



Boreal Zones; southeastern Oregon and adjacent Nevada. Type locality: Steens Mountains, Oregon. 

 June-Aug. 



11. Draba Howellii S. Wats. Howell's Draba. Fig. 2075. 



Draba Howellii S. Wats. Proc. Amer. Acad. 20: 354. 1885. 

 Draba pterosperma Payson, Amer. Journ. Bot. 4: 266. 1917. 

 Draba carnosula O. E. Schulz, Pflanzenreich 4 105 : 82. 1927. 



Cespitose perennial, caudex rather loosely branching. Leaves arising above the ground on 

 sparingly leafy shoots or sobols, oblong, 3-5 mm. long, 1-2 mm. wide, midvein prominent, loosely 

 stellate with short-stalked hairs, ciliate on the margins ; scapes 2-6 cm. long, slender, pubescent ; 

 raceme becoming lax, 6-8-flowered ; petals yellow, 7-8 mm. long ; pods broadly lanceolate, 8-9 

 mm. long, compressed, pubescent with stellate hairs; style 2 mm. long, slender; seeds broadly 

 winged all around, or only at apex. 



Alpine summits, Boreal Zones; Siskiyou Mountains, southern Oregon, to Marble Mountain and Mount 

 Shasta, California. Type locality: Preston's Peak, California. July-Aug. 



12. Draba incerta Payson. Yellowstone Draba. Fig. 2076. 



Draba incerta Payson, Amer. Journ. Bot. 4: 261. 1917. 



Cespitose perennial, the short caudex branches clothed with the old leaf bases. Leaves linear- 

 oblanceolate, 7-10 mm. long, loosely stellate, ciliate with soft pilose hairs toward the base, in age 

 glabrate and bright green on the upper surface ; scapes 4-12 cm. high, sparsely pilose ; inflores- 

 cence becoming a loose raceme in fruit; pedicels ascending, 3-15 mm. long; petals yellow, ob- 

 lanceolate, 5 mm. long; pods broadly lanceolate, 4-8 mm. long, 2-3 mm. wide, cinereous with 

 simple and stellate hairs ; style less than 1 mm. long ; seeds not winged. 



Rocky ridges, Hudsonian Zone, Cascade Mountains of Washington to Alberta and Wyoming. Type 

 locality: among rocks on the summit of Thunderer, Yellowstone Park, Wyoming. July-Aug. 



13. Draba Lemmonii S. Wats. Lemmon's Draba. Fig. 2077. 



Draba Lemmonii S. Wats. Bot. Calif. 2: 430. 1880. 



Cespitose perennial with a compact, very leafy, and much branched caudex, flowering scapes 

 2.5-8 cm. high, pilose or glabrous. Leaves 4-10 mm. long, spatulate to oblong-obovate, obtuse, 

 thick, conspicuously ciliate, otherwise glabrous or sparingly pubescent with simple or 2-3-forked 

 hairs ; racemes short ; sepals sparsely villous ; petals yellow, 4 mm. long ; fruiting pedicels slen- 

 der, spreading, 2-8 mm. long; pods 6-8 mm. long, ovate to broadly lanceolate, more or less 

 undulate or twisted, pubescent. 



Clefts of rocks, on alpine summits, Hudsonian and Arctic-Alpine Zones; Sierra Nevada, California. 

 Type locality: summit of Mount Lyall, at 13,000 feet altitude, California. July-Sept. 



Draba Lemmonii var. cyclomorpha (Payson) O. E. Schulz, Pflanzenreich 4 105 : 94. 1927. Pods gla- 

 brous, otherwise closely resembling the typical species. Boreal Zones, Wallowa Mountains, Oregon. 



Draba cruciata Payson, Amer. Journ. Bot. 4: 265. 1917. Leaves slightly toothed, pubescent, with 

 4-forked hairs, otherwise not unlike D. Lemmonii S. Wats., of which it is probably merely a form. Based upon 

 specimens collected in the vicinity of Mineral King, southern Sierra Nevada, California. 



Draba longisquamosa O. E. Schulz, Pflanzenreich 4 105 : 94. 1927. Differs from D. Lemmonii in the 

 shape and size of the withered leaf bases on the branches of the caudex. An unsatisfactory and apparently 

 inconstant character. Based upon specimens collected by Purpus (5118) somewhere in the southern Sierra 

 Nevada, California. 



14. Draba Paysonii J. F. Macbride. Payson's Draba. Fig. 2078. 



Draba vestita Payson, Amer. Journ. Bot. 4: 261. 1917. Not Davidson. 

 Draba Paysonii J. F. Macbride, Contr. Gray Herb. 56: 52. 1918. 



Densely cespitose perennial, the branches densely clothed with the persistent old leaves. 



