202 COMPOSITE. (composite family.) 



*■ *■ Lowest leaves conspicuously serrate : heads small. 



23. A. cordifolius, L. Stem commonly smooth, racemose-paniclcd above ; 

 leaves smooth, or rough above and pubescent beneath, all cordate, serrate, and 

 Blender-petioled, or the Uppermost on short winged petioles, or sessile and entire; 

 beads very numerous in panicled racemes ; scales of the olxonieal involucre loose- 

 ly imbricated, with obtuse or slightly pointed green tips. — Open woods, in the 

 upper districts. — Stem l°-3° high. Leaves commonly thin. Rays pale violet. 



24. A. sagittifolius, Willd. Stem nearly smooth, racemose-branched 

 above ; leaves ovate-lanceolate, acuminate, pubescent ; the lowest cordate, on 

 long and mostly margined petioles ; the upper abruptly contracted into a winged 

 petiole; those of the branches lanceolate, acute at both ends, entire; beads in 

 dense compound racemes ; scales of the oblong involucre rather loosely imbri- 

 cated, linear-subulate, the tips green and spreading. (A. paniculatus, Ell.) — 

 Rich woods, Florida and northward. — Stem 2° - 3° high. Heads more crowded 

 than those of the preceding. Hays purple. 



# * # * * Leaves linear or lanceolate, entire, sessile ; radical ones sjtatulate-lanceo- 

 late, serrate: heads small and numerous, racemed: scales of the involucre in several 

 rows, rigid, with spreading or recurved green ti]>s. 



25. A. ericoides, L. Smooth ; stem much branched ; leaves linear-lance- 

 olate, acute at each end; those of the branches subulate; heads racemose, mostly 

 on one side of the spreading branches ; scales of the involucre broadest at the base, 

 with acute or subulate tips. — Var. villosus. Stem and broader leaves rough- 

 hairy, and the smaller heads in shorter and more dense racemes. — Var. platy- 

 niYLLUS. Stem (3° -4°) and larger leaves clothed with soft white hairs ; heads 

 larger. — Dry soil, Florida, and northward. — Stem l°-2° high. Rays white 

 or pale blue. 



26. A. multiflorus, Ait. "Whitish-pubescent; stem very leafy, and much 

 branched ; leaves linear, obtuse at each end, often bristle-pointed, spreading or 

 recurved, the upper ones sessile or somewhat clasping; heads densely racemose 

 on the short and very leafy branches, or sometimes solitary at their summits ; 

 scales of the involucre broadest at the apex, obtuse or short-pointed. — Dry 

 sterile soil, in the upper districts. — Stem l°-2° high. Leaves about 1' long. 

 Bays white. 



****** reaves linear, lanceolate, or oblonrj, sessile, usual!)/ narrowed at the 

 base: ln<i<h small or middle-sized: scales of the involucre membranaceous, with n}>- 

 ]tr, ued or slightly s/>r< ading tips .• rays pah' purple or white. 

 +■ Heads small. 



27. A. racemosus, EIL Rough-pubescent ; stem much branched, bear- 

 ing tin- small heads in a spiked raceme near the summit of the Blender erect 

 branches; leaves linear, sessile, rigid ; scales of involucre smooth, linear-tuba 

 late; tin- inner ones as long as the <ii>k ; rays very short. — Damp rich soil, 



PaiU bland, South Carolina. — Stem 2° high. Rays pale purple. 



2ft. A. Baldwinii, Torr. 6 Gray. Rough-pubescent; stem slender, pani- 

 cled above, bearing the solitary or loosely racemose heads on the Blender branch- 



very rough, entire; the lowest ovate, on slender margined petioles, 



