COMPOSITE. (composite FAMILY.) 233 



scales of the involucre linear, acute or rather obtuse, imbricated in 3 or 4 rows. 



Thickets, fields, &c. : very common, and extensively variable. — Leaves larger 

 than in either of the preceding (2' -5'); tiie involacre intermediate between 

 them, as to the form of the scales. Rays mostly short, pale bluish-purple or 

 white. 



■>- ■<- Heads middle-sized. (Involucre 3" - 5" lor>g.) 



22. A. simplex, Willd. Smooth or neariy so (3°- 6° high), much 

 branched ; the branches and scattered heads somewhat corymbose at the summit ; 

 leaves lanceolate, pointed, the lower serrate; scales of the involucre linear-awl-shaped, 

 loosely and sparingly imbricated. — Shady moist banks : common. — Rays pale. 

 Approaches in its different forms the preceding and the two following. 



23. A. tellllif61ius, L. Nearly smooth; stem much branched (2° -3° 

 high); the heads somewhat panicled or racemed; leaves narrowly lanceolate, 

 tapering into a long slender point (2' - 6' long), with rough mat-gins, the lower some- 

 what serrate in the middle ; scales of the hemispherical involucre linear-awl-shaped, 

 very slender-pointed, numerous, closely imbricated. — Low grounds, New York to 

 Wisconsin, and southward. Rays short and narrow, pate purple or whitish. 



24. A. C^rneus, Nees. Smooth, or the branches rough or pubescent; 

 leases lanceolate, somewhat pointed, or the upper shoM and partly clasping; 

 heads racemose along the ascending leafy branches ; scales of the obovate in- 

 volucre lanceolate, abruptly acute, closely imbricated. -^ Moist soil : common. Leaves 

 firm in texture, smooth, or rough above. Rays rather large, bluish, purplish, 

 violet-purple, or almost white. — On a thorough revision of the genus, older 

 names wijl he found and verified for this and No. 22, which here cover a multi- 

 tude of forms. A mutabilis, L., is probably one of them. 



»«»»»» Stem-leaves sessile, the upper more or less clasping ; scales of tlie hemi- 

 spherical involucre loosely more or less imbricated, somewhat equal, with herba- 

 ceous tips, or the outer often entirely herbaceous ; heads middle-sized or large : 

 rays blue or purple. (The species of this group are still perplexing.) 



25. A. SBStivus, Ait. Stem slender, rough, bushy-branched; leaves nar- 

 rowly lancedatedinear) elongated, taper-pointed, entire, with rough margins ; heads 

 corymbose, loose ; scales of the involucre linear, loose; rays large, apparently light 

 blue. (A. laxifolius, Nees.) — Var. i,.«}TiFL6Rns has very slender branches 

 and leaves, and the scales of the involucre unequal and more appressed. — 

 Moist shady places, Ohio to Wisconsin and northward. — Heads about as large 

 as in A. puniceus, in some forms appearing more like A. carneus. Leaves 4' - 

 7' long, i' to J' wide. 



26. A. ITovi-B^lgii, L, Nearly smooth; stem stout; leaves oblong-lanceo- 

 late, pale or somewhat glaucous, serrate in the middle, acute, tapering to each end ; 

 scales of the involucre rather closely imbricated, with broadish acute herbaceous tips ; 

 rays pale blue or purplish. — Low grounds, not clearly known in a wild state. 

 The plant here in view is intermediate between No. 24 and No. 27. — Heads 

 smaller and less sho*y than in the next. 



27. A. longif61iuS,,Lam. Smooth or nearly so; stem branched, corym- 

 bose-panicled at the sumipit ; leaves lanceolate or linear, or the lower ovate-lance*)- 

 late, entire or sparingly serrate in the middle, taper-pointed, shining above ; scales 



