COMPOSITE FAMILY. 197 



* * Scales of the involucre not leafy but loose and slender, all of about the same 

 length, clammy-glandular, leaves entire, 



A. Novse-Anglise, New England A., but everywhere common in low 

 grounds ; the stout hairy stem 4° - 8° high, thickly beset to the top with 

 lanceolate minutely downy leaves, which all have an auricled clasping base ; 

 heads many and large in a crowded corymb ; the rays very numerous and 

 naiTow, violet-purple, or in var. k6seus rose-purple or reddish. 



» » # Scales of the involucre about equal in length, loose and with more or less 

 leaf-like spreading tips, or the outermost whoUi) green : leaves serrate in the 

 middle or sometimes nearly entire : heads loosely corymbed or paniclcd. 

 Low grounds. 



A. preuantholdes. In rich woodlands chiefly N. & W. ; only 1° - 2° 

 high, almost smooth, with lance-ovate leaves coarsely toothed in the middle, 

 tapering above into a long point, and below into a portion narrower than the 

 abruptly dilated heartshaped clasping base ; rays pale blue. 



A. puniceUS, Rkd-stemmed A. In wet grounds, mostly 3° - 6° high, 

 loosely branched, rough-hairy, commonly purple-tinged, with lance-oblong or 

 lanceolate sparingly serrate rough leaves, the base auricled and partly clasping ; 

 scales of involucre slender ; rays long, bright or pale blue. 



A. longifblius, LoNG-LEAVEB A. Smooth or nearly so, l°-4° high, 

 with lanceolate or linear often entire taper-pointed rather firm and glossy leaves, 

 more leaf-like scales to the involucre, and bright blue-purple rays. 



§ 3. With leaves none of them heart-shaped, those of the stem all sessile : heads very 

 small and numerous, racemed or panicled : involucre imbricated in few or 

 several rows : the scales with green tips, the outer successively shorter. 



* In dry open ground, about 1° high ; rays white : scales of the involucre rigid and 



whitish, with abrupt and spreading conspicuous green tips. 



A. ericoldes, Heath-like A. Smooth or rather hairy, with lanceolate 

 or linear-awl-shaped leaves acute at both ends, and scales of the involucre broadest 

 at base, the green tips acute. 



A. multlfldrus, Mant-flowered A. Very common in sterile dry soil, 

 pale or slightly hoary with fine close down, much branched and bush-like, with 

 spreading linear leaves rough or ciliate on their margins, the upper sessile or 

 partly clasping by a broad base ;" scales of involucre spatulate, the green tip 

 shorter than the whitish lower portion. 



* • Inlaw, moist, or shady places, l°-3° High: scales of involucre with short and 



close-pressed green or greenish tips. 



A. Tradescd.nti. Nearly smooth, with slender stems, linear or lance- 

 linear leaves, and very small and numerous heads closely racemed along the 

 upper side of the flowering branches, the scales of the involucre narrow linear 

 and acute ; rays white. 



A. miser. Eather hairy, with lanceolate or lance-oblong thin leaves taper- 

 ing to each end and sharply toothed about the middle, heads loosely racemed or 

 scattered on diverging branches, and with linear rather blunt scales of the invo- 

 lucre ; rays pale blue-purple or white. 



A. dumosus. Bushy A. Smooth or almost so, loosely bushy-branched, 

 with mostly linear entire or slightly serrate rough-edged leaves, and loosely 

 racemed flowering branchlets bearing solitary or few heads ; scales of the invo- 

 lucre linear-spatulate and blunt, closely imbricated in several rows ; rays usually 

 light purple-blue, sometimes nearly white. 



§ 4. With small and very rigid linear sessile leaves, a large head solitary at the 

 end of the simple stem or few branches, the involucre of narrow rigid scales 

 closely imbricated in very many rows, without green tips, and showy violet- 

 blue rays. 

 A. Iinariif61ius, of the older botanists, strictly DiplopXppus linaeii- 

 r6Lius (having a double pappus, the outer of very short bristles) ; common in 

 open gravelly or sandy ground, 6' - 20' high ; the spreading leaves with rough 

 margins, strong midrib, and no veins. 



