COMPOSITAE 



605 



S. linifolius (L.) B. S. P. In dry, usually sandy soil: Canada 

 and Vt. to Ohio, Ga. and La. 

 Conn. Rare and local over the southern half of the state, perhaps 



wanting northward. 

 N. Y. Common on L. I. but rare on S. I. and in the Bronx, 



apparently unknown northward. 

 N. J. Hunterdon, Bergen, Union, Middlesex and Mercer counties, 



increasing southward, especially in the pine-barrens. 

 Pa. Bucks, Delaware and Chester counties. 



Tertiary, common: Cretaceous, common: Older Formations, 

 scattered and decreasing northward. 166-220 days. About sea 

 level. 



S. asteroides (L.) B. S. P. In dry woods: Me. to Fla., Ohio, 

 Ky. and Ala. 



Common throughout the range. 



15. Aster L. 



Plants of salt marshes; leaves fleshy, narrow, entire. 



Perennial; heads 12-25 mm - broad; involucral bracts lanceo- 

 late, acuminate. 

 Annual; heads 6-10 mm. broad; involucral bracts linear- 

 subulate. 

 Plants not of salt marshes; leaves not fleshy. 



A. Basal and lower leaves with relatively broad blades, 

 mostly of an ovate-cordate type and long petioled. 

 Upper cauline leaves not cordate-clasping; lower peti- 

 oles not dilated-clasping. 

 Rays white, violet, or rose. 



Ligules of ray flowers whitish or pinkish, 

 usually 2-toothed; plants not glandular. 

 Involucre ovoid, campanulate or tur- 

 binate; bracts obtuse or rounded 

 at apex; basal leaves usually small. 

 Leaves thin-membranous, smooth or 



nearly so. 

 Leaves thick, firm and rough, at 

 least when dry. 

 Involucre cylindric; bracts tapering to an 

 obtuse tip; basal leaves large, tufted. 

 Ligules of ray flowers violet, usually 3-toothed; 

 plant glandular. 

 Rays blue or purple. 



Bracts of the involucre linear and obtuse or 

 obtusish. 

 Leaves thin, rough; petioles not usually 

 winged. 



1. A. tenuifolius. 



2. A. subulatus. 



3. A. divaricatus. 



4. A. glomeraius. 



5. A. Schreberi. 



6. A. macro phylius. 



7. A. cordifolius. 



