MUSTARD FAMILY 97 



Eefs. — Draba coreugata Wats. Bot. Cal. 2:430 (1880), type loc. Mt. San Gorgonio (Gray- 

 back), Lemmon; Jepson, Man. 445, fig. 435 (1925). D. vestita Dav., Bull. S, Cal. Acad. 15:17, 

 pi. (1916), type loc. Mt. San Antonio, Fred Burlew. D. saxosa Dav. I.e. 19:11 (1920), type loc. 

 Mt. San Jacinto summit, Davidson. D. corrugata var. saxosa M. & J. Bull. Torr. Club 49:352 

 (1922). 



11. D. howellii Wats. Rosette Draba. Flowering steins naked, 2 to 4 inches 

 high, arising from the densely leafy cushion of the much-branched root-crown; 

 herbage finely soft-pubescent throughout; leaves in very dense somewhat globular 

 rosettes, II/2 to 2 lines long, the blades broadly spatulate or oblong, mostly very 

 obtuse, sessile or narrowed to a broad petiole; flowers large (3 to 4 lines long), in 

 loose racemes; petals deep yellow; pods oblong, often somewhat oblique or subfal- 

 cate, acute at each end, pubescent, 2 to 4 lines long, on pedicels 2^^ to 4 lines long, 

 the style slender, 1 to 1^/^ lines long; seeds winged, narrowly on the sides, rather 

 broadly at apex. 



Montane, crevices of rocks, about 7000 to 7500 feet : Siskiyou Mts. ; Marble Mt. 

 June. 



Locs. — The original plants were obtained by Howell in the Siskiyou Mts. of California, un- 

 doubtedly on Preston Peak (cf. Schulz in Pflzr. 4^"S:82). Seeds of the Preston Peak plant are 

 described by Schulz as provided with a membranous appendage at apex ("apice appendicula 

 membranacea instructa"). The Marble Mt. plants of Siskiyou Co. (Butler 33, 1716, Chandler 

 1654) have the seeds winged except at base, but always most broadly at apex and rather nar- 

 rowly on the sides. In an occasional seed the wing on the side is extremely narrow. We are, 

 therefore, inclined to retain the Marble Mt. plants (D. pterosperma Payson) as representing a 

 rather natural variation under D. howellii. 



Eefs. — Draba howellii Wats. Proc. Am. Acad. 20:354 (1885) type loc. Siskiyou Mts., Cal., 

 Howell; Jepson, Man. 445 (1925); O. E. Schulz in Engler, Pflzr. 4"=:81 (1927). D. ptero- 

 sperma Payson, Am. Jour. Bot. 4:266 (1917), type loc. Marble Mt., Butler 1716. 



D. carnosula O. E. Schulz in Engler, Pflzr. 4t''>^:82 (1927), type loc. Mt. Shasta (n. side), 

 E. E. Brown 463 ; leaves fleshy. 



12. D. oligosperma Hook. var. subsessilis 0. E. Schulz. Mono Draba. Flower- 

 ing stems naked, slender, ^ to 2^4 inches high, pilose or glabrate, few-flowered, 

 arising from the dense cushion of the much-branched root-crown; leaves linear to 

 oblong, sessile or subsessile, in dense terminal rosettes on the branches of the root- 

 crown, 1 to 2 (or 3) lines long, mostly grayish-pubescent; sepals sparingly villous 

 or glabrous; petals yellowish, fading white; pods ovate to ovate-oblong, acute, 

 rounded (or sometimes acute) at base, strongly flattened or rarely a little thick- 

 ened, usually finely pubescent, 1 to 3 lines long on pedicels 1 to 6 lines long; style 

 % to % line long; seeds 2 to 4 or 6. 



Alpine summits and high ridges, in rocky places, 11,600 to 13,300 feet : Sierra 

 Nevada from Mariposa Co. to Nevada Co.; "White Mts.; Mono Co. East to the 

 Rocky Mts., north to British America. July. 



Locs. — Our high alpine plants (Nevada Co. to Mariposa Co.) with short leaves and short 

 flowering stems are quite uniform save in pubescence of the foliage. The following variation in 

 this feature may be noted: (a) leaves densely stellate-pubescent and ciliate, at least at base 

 (Tinkers Knob, Sonne, Mt. Dana, Brewer 1735a, Sheep Mt., White Mts., Jepson 7312, White 

 Mountain Peak, Jepson 7388) ; (b) leaves ciliate and glabrate (Mt. Warren, Congdon, Mt. Dana, 

 Jepson 3292a, Mt. Stanford, Nevada Co., Sonne) ; (c) leaves stellate-pubescent (Mt. Dana, Lem- 

 mon, Chesnut 4" Drew). The pods are somewhat thickened in the following: White Mts., Mono 

 Co., Shockley 455; Mt. Kose, Washoe Co., Nev., Kennedy. 



Var. saximontana O. E. Schulz. Scapes glabrous; sepals occasionally glabrous. — White 

 Mts., Inyo Co. North to British Columbia, east to Wyoming. 



Var. pectinata Jepson comb. n. Taller (3 to 4% inches high) and with greener glabrous 

 ciliate-pectinate leaves. — Castle Peak, Sonne; Mt. Lola, Lemmon; Lake City Pass, Modoc Co., 

 Austin <$• Bruce. 



Eefs. — Draba oligosperma Hook. Fl. Bor. Am. 1:51 (1829), type loc. Mackenzie Eiver, lat. 

 68°, British America, Richardson. Var. subsessilis O. E. Schulz; Engler, Pflzr. 4"=:100 (1927). 

 D. subsessilis Wats. Proc. Am. Acad. 23:255 (1888), type loc. White Mts., Mono Co., W. E, 

 Shockley 455. D. glacialis Gray, Syn. Fl. r:112 (1895); Jepson, Man. 445, fig. 436 (1925). 



