COMPOSITE. (COMPOSITE FAMILY.) 195 



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

 names will be found and verified for this and No. 21, which here cover a mul- 

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



****** Stem-leaves sessile, the upper more or less clasping : scales of the hem- 

 ispherical involucre loosely more or less imbricated, somewhat equal, ivith hei'baeeous 

 tips, or the outer often entirely herbaceous: heads middle-sized or large: rays blue 

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



24. A. aestiVMS, Ait. Stem slender, rough, bush y-branched ; leaves nar- 

 rowly lanceolate-linear, 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. ljetiflO>rds has veiy slender branches 

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

 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, 4/ to £' wide. 



25. A. Novi-ISCIg'ii, 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. 23 and No. 26. — Heads 

 smaller and less showy than in the next. 



26. A. lOHgifdiius, Lain. Smooth or nearly so ; stem branched, corym- 

 bose-panicled at the summit; leaves lanceolate or linear, or the lower ovate-lance- 

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

 of the involucre imbricated in 3-5 rows, linear, ivith acute or awl-shaped spreading or 

 recurved green tips ; rays large and numerous, bright purplish-blue. — Moist 

 places, along streams, &c, common eastward. — Plant l°-5° high, with large 

 and showy heads; very variable in the foliage, involucre, &c. ; its multiform 

 varieties including A. thyrsiflorus, Hoffm., A. laxus, Wilhl. (a form with more 

 leafy involucres), A. prsealtus, Poir., A. clodes, Torr. Sf Gr., &c. 



27. A. puiaicciis, L. Stem tall and stout, rough-hairy all over or hi lines, 



usually purple below, panicled above; leaves oblong-lanceolate, clasping by an auri- 

 cled base, sparingly serrate in the middle ivith ap/irrsscd teeth, rough above, nearly 

 smooth underneath, pointed ; scales of the involucre narrowly linear, acute, loose, 

 equal, in about 2 rows ; rays long and showy (lilac-blue, paler or whitish in 

 shade). — Low thickets and swamps, very common. — Stems 3° -6° high, in 

 open grounds rough with rigid bristly hairs. 



Var. vimiltctlS (A. vimineus, Willd.) is a variety nearly smooth through- 

 out ; growing in shade. 



28. A. pi'CBiaiitSioides, Mnhl. Stem low (l°-3° high), corymbose- 

 panicled, hairy above in lines; leaves rough above, very smooth underneath, ovate-lan- 

 ceolate, sharply cut-toothed in the middle, conspicuously taper-pointed, and teipering 

 below in a long contracted entire portion, which is abruptly dilated into an auricled- 

 heart-shaped clasping base ; scales of the involucre narrowly linear, with recurved- 

 spreading tips ; rays light blue. — . Borders of rich woods, W. New York and 

 Penn. to Wisconsin. 



