coMPOsfr^. (composite FAivnLT.) 257 



sharpli/ serrate in the middle, very rough both sides and rugose-veined, closely 

 sessile (2-3' long), nearly equal; scales of the hell-shaped involucre oblong, ap- 

 pressed, tcith ven/ short and slighthj spreading herbaceous tips ; achenes smooth. 



— Bogs aud low grounds, Del. to Maine and northward, near the coast ; also 

 Pocono ^Mountain, Penn. A dwarf form (var. strIctus, Gray) has oblong- to 

 linear-lanceolate nearly entire leaves, and usually solitary heads ; White Moun- 

 tains, N. H., to Lab. Aug. — Kays light violet. Involucre nearly smooth, 

 except the ciliate margins. 



* 2. Involucre and usually the branchlets viscidhj or pruinose-glandular, well 

 imbricated or loose ; pubescence not silkij ; leaves entire {or the lower ivith 

 few teetli), the cauline all sessile or clasping ; raijs showj/, violet to purple. 



H- Heads small ; involucre not squarrose. Extreme western. 



9. A. Fendleri, Gray. Rigid, 1° high or less; leaves firm, linear, 1- 

 nerved, hispid-ciliate, 1' long or mostly much less; heads scattered, 3" high; 

 scales linear-oblong, obtuse, or the inner acute. — Central Kan. (Ellis, Dr. L. 

 Watson) aud southwestward. 



-t- -i- Heads larger ; involucral scales spreading, infeiv or many ranks. 



10. A. grandifl6rTlS, L. Rough with minute hispid hairs; stems slender, 

 loosely much branched (1-3° high); leaves very small (i-1' long), oblong- 

 linear, obtuse, rigid, the uppermost passing into scales of the hemisplierical 

 squarrose many-ranked involucre; rays bright violet (1' long) ; achenes hairy. 



— Dry open places, Va. and southward. — Heads large and very showy. 



11. A, oblongifolius, Nutt. Minutely glandular-puberulent, much 

 branched above, rigid, paniculate-corymbose (1-2° high) ; leaves narrowly ob- 

 long or lanceolate, mucrouate-pointed, partly clasping, thickish (1-2' long by 

 2 - 5" wide) ; involucral scales nearly equal, broadly linear, appressed at the 

 base ; rays violet-purple ; achenes canescent. — Banks of rivers, from Penn. 

 and Va. to Minn, aud Kan. — Heads middle-sized or smaller. 



Var. rigidulus, Gray. Low, with more rigid and hispidulous scabrous 

 leaves. — In drier places, 111., Wise, and southwestward. 



12. A. Novae-Anglise, L. Stem stout, hairy {3-8° high), covymheda,t 

 the summit; leaves very numerous, lanceolate, entire, acute, auriculate-clasping, 

 clothed with minute pubescence, 2-5' long ; scales nearly equal, linear-awl -sha])ed , 

 loose, glandular-viscid, as well as the branchlets; rays violet-purple (in var. 

 r6seus rose-purple), very numerous ; achenes hairy. — Moist grounds ; com- 

 mon. — Heads large. A peculiar and handsome species. 



13. A. modestus, Lindl. Pubescent or glabrate ; stem slender, simple, 

 with few large heads terminating slender branchlets; leaves lanceolate, very 

 acute, narrowed to a sessile base, sparingly serrate or serrulate ; scales linear 

 attenuate, equal, mostly herbaceous ; rays blue. — N. Dak. and westward. 



* 3. Leaves ivhitened, silvery-silky both sides, all sessile and entire, mucronulate ; 

 involucre imbricated in 3 to several rows ; rays showy, purple-violet. 



14. A. sericeus, Vent. Stems slender, branched; leaves silver-white, 

 lanceolate or oblong, heads mostly solitary, terminating the short branclilets ; 

 scales of the globular involucre similar to the leaves, spreading, except the short 

 coriaceous base; achenes smooth, many-ribbed. — Prairies and dry banks. Wise 

 and Minn, to Ky., and southward. — Heads large; rays 20-30. 



