COMPOSITE. (COMPOSITE FAMILY.) 221 



all on slender petioles, and obtuse or cordate at the base, commonly entire ; 

 those of the branches obloi.g, sessile ; scales of the bell-shaped involucre 

 linear, closely imbricated, rather obtuse, shorter than the disk. Mountains 

 of ( ieurgia, and westward. Stem 2 -4 high. Kays violet-blue. 



-'1 . A. undulatus, L. Pubescent ; stem racemose-panicked above ; leaves 

 varying from lanceolate to broadly ovate, often wavy or slightly serrate on 

 tiie margins, roughish on the upper surface; the lowest on long and slender 

 petioles, which are dilated and clasping at the base ; the upper on broadly 

 winged petioles, or sessile and clasping ; scales of the obovoid involucre lin- 

 ear, appressed, acute. (A. scaber, Ell., with the smaller leaves very rough 011 

 both sides.) Woods, common aud very variable. Stem 2 - 3 high. Heads 

 small. Kays pale blue. 



*- *- Lowest leaves cons[>icuousli/ serrate : heads sina//. 



22. A. COrdifolius, L. Stem commonly smooth, racemose-pauicled 

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

 serrate, and slender-petit >led, or the uppermost on short winged petioles, or 

 sessile and entire ; heads very uumerous in panic-led racemes ; scales of the 

 obconical involucre loosely imbricated, with obtuse or slightly pointed green 

 tips. < )pen woods, in the upper districts. Stem l-3 high. Leaves com- 

 monly thin. Kays pale violet. 



23. 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 ; 

 heads in dense compound racemes; scales of the oblong involucre rather 

 loosely imbricated, linear-subulate, the tips green and spreading. Kich 

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

 than those of the preceding. Rays purple. 



* 5. Leaves linear or lanceolate, entire, sessile ; radical ones spatulate-lanceolate, 

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

 roics, rigid, with spreading or recurved green tips. 



24. A. ericoides, L. Smooth ; stem much branched ; leaves linear-lan- 

 ceolate, 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. PLATYPHTLLUS. 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. 



Var. Reevesii, Gray. Stem l-2 high, branching from near the base ; 

 smooth, or papillose-hispid ; leaves linear, the lowest hispid-ciliate ; heads 3"- 

 4" long, on thickly bracted pedicels. Nashville, Tennessee. 



25. A. polyphyllus, Willd. Nearly glabrous ; stem 4 -5 high, much 

 branched ; leaves linear-lanceolate, long-acuminate, the lower sharply serrate, 

 3' -5' long; heads racemose at the end of the branches; involucre scales 

 linear or linear-subulate, appressed ; rays short, white. North Carolina 

 (Gray), and northward. 



