182 DICOTYLEDONOUS PLANTS. 



8. A.paludosus Ait. : stem simple; leaves sessile or clasping, subu- 

 late, smooth, with the margin scabrous; peduncles few, 1-flowered, 

 axillary and terminal, leafy, pubescent; involucre large and squarrose. 

 A. grandiflorus Walt. ? 



HAB. Borders of swamps. N. J. to Flor. Aug. Nov. 21. 

 Stem 12 feet high, smooth nearly to the top, 3 5-flowered. 

 Flowers very large and beautiful, the rays bright blue. 



9. A. muUiflorus Ait. : stem diffusely branched, pubescent ; leaves 

 linear, entire, nearly smooth, slightly ciliate ; involucre and peduncles 

 squarrose, the scales oblong and ciliate. A. multiflorus and A. citiatus 

 mild. 



HAB. Fields and road sides. Can. to Car. Aug. If. Stem 

 2 3 feet high, branching, very pubescent. Flowers in crowded 

 terminal racemes, on horizontal branches. Kay florets nearly 

 white, disk ones yellowish. 



10. A. sparstforus Mck. : very smooth ; stem slender, much branch- 

 ed ; leaves linear-subulate, somewhat fleshy and reflexed ; branches 

 spreading, leafy, 1-flowered ; scales of the involucre acute, appressed. 



HAB. Salt marshes. N. Y. to Car. Sept; Nov. 2j..Stem 

 12 feet high. Flmcers large; rays pale purple ; disk yellow. 



11. A. concolor Linn. : stem simple, erect, pubescent ; leaves oblong- 

 lanceolate, entire, hoary and pubescent on both sides ; raceme termi- 

 nal ; scales of the involucre lanceolate, silky, appressed. 



HAB. Pine woods. N. J. to Flor. Aug. Nov. If. Stem 2-3 

 feet high, sparingly branched. Flowers in a long terminal ra- 

 ceme, blue. Root often tuberous. 



12. A. salicifolius Pursh : stem smooth, paniculate at the summit ; 

 leaves linear-lanceolate, nearly entire, smooth ; involucre lax, with the 

 scales acute and spreading at their summits. A. prealtus Lam. 



HAB. Low grounds. N. S. Aug. Oct. 2f. Stem 4 6 feet 

 high. Flowers middle-sized, reddish-blue. 



13. A. astitus Alt. : stem branching from the base, erect, hispid ; 

 branches hairy ; leaves lanceolate, subclasping, attenuate at the apex, 

 with the margin scabrous ; scales of the involucre loose, linear, acute, 

 equal. 



HAB. Dry swamps. N. S. July Sept. If. Stem 2 feet high. 

 Flowers middle-sized ; rays blue. 



14. A. noraawglioi Linn. : stem erect, hairy, paniculate ; leaves nar- 

 row-lanceolate, hairy, clasping, auriculate, crowded on the branchlets ; 

 scales of the involucre lanceolate, loose, rather longer than the disk. 



HAB. Meadows. Can. to Car. Sept. Nov. If.. Stem 36 

 feet high, almost hispid, with spreading branches. Flowers 

 large, in a loose terminal panicle, blue or purple. A very orna- 

 mental species. 



15. A. cyaneus Pursh : stem very smooth, branching, the branches 

 spreading ; leaves linear-lanceolate, clasping, smooth ; flowers in pani- 



