• COMPOSITAE (composite FAMILY) 531 



4ster-like; rays ' broad, i (iomparatively few; disk-flowers numerous. Style- 

 appendages, short, triangular-cuspida,te. Achenes short, densely pubescent, 

 ' svfbterete.^Bri^eron m part. ,, ^ | - : •■ n.i 



CTaudex merely anenlarged crown, or the branches, if any! very short.' 

 Glistening silvery-white^ the .pubescence microscopically nne,,ap- 



; pressed . . . . . ; 1. W. argentata. 



Greenish but more or leas cinereous-lanate. 

 ''■ Leaves 'short, mostly 1^3 'cm. Ibng . . ' ^ , . ,2. W. cana. 



Leaves long, mostly 4-8 cm. long . , ,, . . ,3. W. Tweedyaua. 

 Caudex freely branched, forming a dense tuft, with one or more stems 

 'I I- , from each' crown. '!'"., , , : , ! 



I I^eaves 1-^ mm. Wjide; stems slender, curved-ascending , . ,, 4. W. p\ilcherrima. 

 Leaves 2-5 mm. wide; stems '^to^tisn, strict ..... '5. W. cinefea. 



i 1. Wyomingia ' argentata (Gray)i A. Nels. Silvfery white pubescence 

 throughout very close and fine, the separate hairs indistinguishable;, stems 

 1-3 dm. high: radical lea-wes very densely clusitered, linear-spatulate or broader, 



,J!3tii5 cm. long; the cauline scattered and much smaller: heads broad, 12-^15 mm. 



"high: rays rather broad and large, 12-14 mm. long: achenes sericeous-pubescent 

 or villous,! 5-8-nerved. {Erigeron argentatus Gray, Proc. Am. Acad. &: 649. 

 1873.)*— Desert regions of western Colorado to Utah and Nevada. ■!,, j\ 



2. Wyomingia cana (Gray) A. Nels. _ Silvery appressed pubescence ob- 

 viously strigillose imder a leils,rthat) of theiivvolucre loose and spreading: stems 

 1-2 dm. high, leafy: 'the linear cauline leaves gradually diminishing upy^ard; 

 tl}e radical sp^,tulate-lafaceblate or narrower: head about 8 mm. high:' rays 

 narrow, 6 mm. Jong: acheneS; glabrous. {Erigeron canus Gray, PI. Fendl. 67. 

 1848.) — Arid areas; Vestern Nebraska to Wyoming and New Mexico. 



3. Wyomingia Tweedyana (tanby &' Rose) A. Nels. Peranhial, from a mul- 

 ticipital caudex, 1-2 dm. high, simple or somewhat branched, soft-pubesc6nt 



' bjelbw, becoming linate above (apparently densely wbite, lanate T^heri yotirig) : 

 ieavep narrowly linear, 4-8 cin. long, crowded at base, rediiced and scat- 

 tered above, somewhat pubescent: heads 6-iCi mm. high, a little' broader, 

 terminating the simple stems or the branches: the peduncles-long and naked 

 or,with few, bract-^Uke leai'Ves: involucrfe of numerous harrow acuminate bracts, 

 so crowded as to seem but 1-2 series, with tips a little spreading, (i^ei^sely 

 lanate: rays numerous, conspicuous, white: pappus double, the outer mul- 

 tisquajnellate; achenes pubescent. {Erigeron Tweedyafm Canby & Rose, 

 fiot. Gaz. 15: 65. .1890; E. wMntanensis Rydb-BuU. TorrJ Bot. Cliib 24: 296. 

 1898.) — Arid districts; Montana. 

 ■''' ■ 4. Wyomingia, pulcherrima (Heltef)' A.-Nels. Bull. Torr. Bot. Club 26: 249. 



-18^9'. Stems about 20 cm. hfigh, tufted at the base, simple, slender, leafy, 

 with prominent yfeUowish lines,' pubescent with short, appressed, white hairs: 

 leaves "all very narrow, about ,1 mm. wide; the basal' ones linear-spatUlate, 

 about I'.S cm. long; those of the stems 2-4 cm. long, hnear, acute: white- 

 pubesceht: peduncles a prolongation of the stems, 2-5 cm. long; heads large, 



'3.5 cm. in diameter, 7 mm. high; involucral bracts in about 4 rows, slightly 

 spreading; linear-lanceolatei, ' with spreading' pubescence: rays 20-30, either 

 ■white, pinkish, br'viotet blii^,- 1.5 cm.-loilg,'2 mm. -wide, emarginate.— -Sandy 



' hills; New Mexico and probably southern Coldrado. 



'5. Wypmiagia cinerea A. Nels. 1. c. 250;' Stems erect, fascicled, somewhat 

 striate -with yellbwish'-green lines; about '2 dm. high, the upper part naked- 

 pedunculate, usually with a single bract: leaves linear or some of the crown 



''leaves spatulate, acute, cinereous '(as are'also the stems) with a short,' close, 



'iappressed pubescence: heads large, when fully open 3 cm. or more across; 

 inyotocre broadly hemispherical, about 1 cm. high; the bracts acute, cinereous 

 with a spreading, Crinkled pubescence: Tays 30 (more or less), 5-7-nervecl, 

 White'ttr pinkish, the tube finely pubesceni; as are also the disk florets, 3 mm. 



' broad, 3-toothed at the rounded ap&i: pappus tawny.'ih a single series, about 



'as long as the disk-corollas, the bristles mostly abruptly fiexed' one third their 

 length' 'by ow the apex: adhene short, striately marked with 2-4 greenish- 

 j^ell6w Hnes: reCSpticle flat, alveolate. — Desert hillsides; south central VVyo^ 

 ming. 



