COMPOSITE. (COMPOSITE FAMILY.) 193 



underneath, lanceolate or ovate-lanceolate, elongated, tapering gradually to a sharp 

 point, all but the uppermost more or less heart-shaped at the base and on naked peti- 

 oles ; involucre bell-shaped. — Cliffs and banks, Ohio to Wisconsin and south- 

 ward. — A pretty species, 2° -4° high ; the leaves 3 '-5' long. 



13. A. ItmlulutUS, L. Pale or somewhat hoary with close pubescence ; 

 stem spreading, bearing numerous heads in racemose panicles ; leaves ovate or 

 ovate-lanceolate, with wavy or slightly toothed margins, roughish above, downy under- 

 neath, the lowest, heart-shaped on margined petioles, the others abruptly contracted 

 into short broadly winged petioles which are dilated and clasping at Vie base, or direct- 

 ly sessile by a heart-shaped base; involucre obovoid. (A. diversif-Jlius, Michx.) 

 — Dry copses, common. 



*- ■•- Leaves conspicuously serrate: heads small : rays pale blue or nearly white. 



14. A. corilifolius, L. Stem much branched above, the spreading or 



diverging brandies bearing very numerous panicled heads: lower leaves all heart- 

 shaped, on slender and mostly naked ciliate petioles ; scales of the inversely coni- 

 cal involucre all oppressed and tipped with short green points, obtuse or acutish. — 

 Woodlands ; very common. Varies with the stem and leaves either smooth, 

 roughish, or sometimes hairy underneath. Heads produced' in great profusion, 

 but quite small. 



15. A. saprittifdiiltS, Willd. Stem rigid, erect, with ascending branches 

 bearing numerous racemose heads; leaves ovate-lanceolate, pointed; the lower 

 heart-shaped at the base, on margined petioles; the upper lanceolate or linear, 

 pointed at both ends ; scales of the oblong involucre linear, tapering into awl-shaped 

 slender and loose tips. — Dry ground, New York and Penn. to Wisconsin and 

 Kentucky. — Usually more or less hairy or downy; the heads rather larger 

 than in the last, almost sessile. — A. Drummondii, Lindi, which probably 

 grows on the Illinois side of the Mississippi, is apparently only a downy-leaved 

 variety of this. 



# •* * * Leaves none of them heart-shaped ; those of the stem scssil '■ , harrow, rigid, 

 entire : involucre imbricated in several rows : the coriaceous scales oppressed and 

 whitish at the beise, with abrupt and conspicuous spreading herbaceous tips : heads 

 small and very numerous, paniculate-racemose : trigs v:' 



16. A. CB'iCOideS, L. Smooth or sparingly hairy (l°-l£° high); the 

 simple branchlets or peduncles racemose along the upper side of the wand-like 

 spreading branches ; lowest leaves oblong-spatulate, sometimes toothed; theothem 

 linear-lanceolate or linear-awl-shaped, acute at both ends; scales of the involucre 

 broadest at the base, with acute or awl-shaped green tips. — Var. vill6sus is a 

 hairy form, often with broader leaves; chiefly in the Western States. — Dry 

 open places, S. New England to Wisconsin and southward. 



17. A. imcltiflds'tlS, Ait. Pale or hoary with minute close pubescence (1° 

 high), much branched and bushy; the heads much crowded on the spreading 

 racemose branches ; leaves crowded, linear, spreading, with rough or ciliate. mar- 

 gins, the upper somewhat dilated and partly clasping at the base ; scales of the invo- 

 lucre with spatulate spreading green tips broader than the lower portion, the outer 

 obtuse. — Dry gravelly or sandy soil ; common. 



17 



