GENUS 35. THISTLE FAMILY. 
3. Erigeron subtrinérvis Rydberg. Three- 
nerved Fleabane. Fig. 4363. 
Erigeron glabellus var. mollis A. Gray, Proc. Acad. 
Phila. 1863: 64. 1864. Not E. mollis D. Don. 
Erigeron subtrinervis Rydberg, Mem. Torr. Club 5: 
328. 1894. 
Similar to the preceding species, perennial by 
a woody root, finely pubescent all over; stems 
leafy to the inflorescence. Leaves entire, thin, the 
basal and lower ones oblanceolate to oblong, ob- 
tuse or acute, petioled, the upper lanceolate or 
ovate-lanceolate, sessile or somewhat clasping, 
acute, rather distinctly 3-nerved; heads 1’-12’ 
broad, corymbose, or rarely solitary; involucre 
hemispheric, hirsute ; rays numerous, blue to pink; 
pappus double, the outer bristles very short. 
437 
In dry soil, South Dakota to Wyoming, Nebraska, 
July-Sept. 
Utah and New Mexico. 
5. Erigeron ptmilus Nutt. 
Daisy. Fig. 4365. 
Erigeron pumilis Nutt. Gen. 2: 147. 
Perennial by a deep root; stems tufted, hirsute, slen- 
der, simple, or branched, 4’-10’ high. Leaves entire, 
hirsute, the lower and basal ones narrowly spatulate or 
linear, petioled, obtuse or acutish, 1-4’ long, 1’-2” wide; 
stem leaves linear, sessile, 4’-23’ long, acute; heads soli- 
tary or several, 6-10” broad, short-peduncled; invo- 
lucre hemispheric, its bracts linear, acute, hirsute; rays 
50-80, white, 3-4” long, at length deflexed; pappus 
double, the outer row of bristles short and more or less 
intermixed with the inner; achenes pubescent. 
Dry plains, North Dakota to western Nebraska, Kansas, 
British Columbia, Colorado and Utah. May-Sept. 
Low Erigeron. 
4. Erigeron caespitésus Nutt. Tufted 
Erigeron. Fig. 4364. 
Diplopappus canescens Hook. Fl. Bor. Am. 2: 21. 
1834. Not E. canescens Willd. 1804. 
Erigeron caespitosus Nutt. Trans. Am. Phil. Soc. (II) 
7: 307. 1841. 
Perennial by a deep root; stems tufted, canes- 
cent, simple, or branched above, 6-12’ high. 
Leaves canescent or pubescent, entire, the lower 
and basal ones petioled, narrowly oblanceolate 
or spatulate, obtuse or acutish, 1-3’ long; stem 
leaves linear or linear-oblong, acute or obtuse, 
sessile, the upper gradually shorter, heads soli- 
tary or several, short-peduncled, 1’-13’ broad; in- 
volucre hemispheric, its bracts lanceolate or linear- 
oblong, acute, canescent; rays 40-60, 3-6” long, 
white or pinkish; pappus double, the outer series 
of bristles very short. 
In dry soil, Manitoba to Yukon, Nebraska (accord- 
ing to Webber), British Columbia and Colorado. 
June-Aug. 
