374 COMPOSITE arnica 



SENECIO 



A. Ion gifolia Eaton Bot. King 186. Minutely scabrous-puberulent : 

 stems 14-24 inches high, many from a scaly caudex: leaves in 5-6 pairs, elon- 

 gated-lanceolate, acuminate, 7-10 lines broad, entire or denticulate, the very 

 lowest reduced to ochreate scales, the upper pairs sessile and slightly conna- 

 te-amplexicaul, the lower with sheathing connate petioles: heads 1-8, com- 

 monly 5, not large; involucral bracts lanceolate, acute: achenes minutely 

 glandular but not hispid. In dense clumps among rocks, Powder River 

 Mountains Oregon to the Clover Mountains Nevada and in the Uintas above 

 Bear River Canyon; 10,000 feet altitude. 



A. folios a Nutt. 1. c. Tomentose-pubescent, strict, leaves lanceolate, 

 denticulate, nervose; upper partly clasping by narrowish base; lower with 

 tapering base, connate: heads short-peduncled, rarely solitary; achenes hir- 

 sute-pubescent or glabrate. Wet meadows and mountain sides, western Cali- 

 fornia to eastern Washington the Saskatchewan and the Rocky Mountains. 



+- +- Heads rayless stems leafy even on the flowering branches 



A. viscosa Gray. Proc. Am. Acad, xiii, 374. "A foot or less high, fas- 

 tigiately branching, very viscid-pubescent: leaves small (inch or less long), 

 ovate-oblong, entire, closely sessile but not connate at base: involucre 4 lines 

 high, considerably 'shorter than the 25 or 30 flowers: corollas pale yellow: ach- 

 enes glandular-hirsute. On Mt. Shasta California", perhaps in Oregon. 



+- ■+ Less leafy: cauline leaves 1 or 2 rarely 3 pairs, the upper 

 mostly small. 



+* Heads rayless, mostly 3-5 and rather short-peduncled at the naked 

 summit of the stem. 



A. Parryi Gray Am. Nat. viii, 213. Somewhat hirsutely pubescent 

 and above glandular, slender, simple, 1-2 feet high: leaves membranaceous, 

 commonly denticulate, radical oval or ovate-oblong, 1-3 inches long, ab- 

 ruptly or cuneately contracted at base into a short margined petiole; cau- 

 line remote : involucre hirsute and glandular, 6 lines or less high, occas- 

 ionally some outermost corollas ampliate : achenes glabrous or with a few 

 sparse hairs. Eastern Oregon and Washington to the Rocky Mountains. 



++ ** Heads conspicuously radiate, solitary or very few, mostly 

 long-peduncled. 



A. alpina Olin. Pubescent, hirsute or at summit villous: stems 18 

 inches high. Strict, simple, usually monocephalous : leaves thickish.from 

 narrowly oblong to lanceolate or the racU a l oblong-spatulate and small, 

 uppermost linear entire, or denticulate, 3-nerved; base of the cauline bare- 

 ly at all connate : achenes hirsute-pubescent, rarely glabrate. Oregon and 

 Washington to the Aleutian Islands, the Rocky and Sierra Nevada Moun- 

 tains Labrador and the Arctic coast 



+ + ++ Pappus of soft-capillary and merely scabrous very nu- 

 merous bristles. Style-branches narrow^ truncate or capitellate and 

 often bearing a bearded ring at tip which sometimes is produced into 

 a short central cusp or obscure cone. Leaves all alternate. 

 86 SENECIO Tourn. L. Gen. n. 954. 



Perennial herbs ; with mostly simple stems from creeping root- 

 stocks, bearing solitary or few usually long-peduncled and rather 

 large heads of yellow flowers. Head many-flowered, with pistillate 

 rays; or sometimes homogamous by the absence of the rays; the 

 flowers all fertile. Involucre usually broadly campanulate na- 



