n6 



COMPOSITAE. 



Vol III. 





22. Aster sagittifolius Willd. Arrow- 

 leaved Aster. Fig. 4303. 

 Aster sagittifolius Willd. Sp. PI. 3: 2035. 1804. 



Stem stout, or slender, strict, glabrous, or spar- 

 ingly pubescent above, 2-5 high, paniculately 

 branched at the inflorescence, the branches as- 

 cending. Leaves thin, slightly roughened, or gla- 

 brous above, glabrate or pubescent beneath, the 

 lower and basal ones cordate or sagittate, ovate- 

 lanceolate, sharply serrate, acuminate, 3'-6' long, 

 with slender naked or narrowly margined peti- 

 oles ; upper leaves lanceolate, sessile, or on short 

 and usually margined petioles, serrate or entire, 

 those of the branches very small; heads 2i"-4" 

 high, 8"-io" broad, numerous, crowded, race- 

 mose ; involucre turbinate, its bracts linear-subu- 

 late, glabrous or nearly so, their tips green and 

 slightly spreading; rays 10-15. light blue or pur- 

 plish, 3"-4" long; pappus whitish. 



In dry soil, New Brunswick to Ontario, North Da- 

 kota. New Jersey, Georgia and Missouri. Aug.-Oct. 



Aster Saundersii Burgess, of the Dakotas and 

 Iowa, differs by a corymbose inflorescence. 



23. Aster undulatus L. Wavy-leaf 

 Aster. Fig. 4304. 



Aster undulatus L. Sp. PI. 875. 1 753- 



Stem stiff, very rough and pubescent, divari- 

 cately branched above, l-3i high. Leaves 

 usually thick, rough on both sides, pubescent 

 beneath, dentate, undulate or entire, acute or 

 acuminate, the lowest and basal ones ovate, 

 cordate, 2-6' long, with naked or margined 

 petioles; middle ones ovate, lanceolate or ob- 

 long, with margined petioles dilated and clasp- 

 ing at the base, the upper sessile or clasping, 

 those of the branches small and subulate; 

 heads numerous, racemose and often fecund 

 on the spreading branches, about 4" high, 

 8"-io" broad; involucre broadly turbinate, its 

 bracts linear-oblong, pubescent, acute or acut- 

 ish, their green tips appressed ; rays 8-15, pale 

 blue to violet, 3"-S" long; pappus whitish. 



In dry soil. New Brunswick and Ontario to 

 Minnesota, Florida. Alabama, Louisiana and 

 Arkansas. Various-leaved aster. Races differ in 

 leaf-form and inflorescence. Sept.-Oct. 



24. Aster patens Ait. Late Purple 

 Aster. Purple Daisy. Fig. 4305. 



Aster patens Ait. Hort. Kew. 3: 201. 1789. 

 A. patens gracilis Hook. Comp. Bot. Mag. 1 : 97- 



1S35- 



Stem slender, rough, i-3 high, diver- 

 gently branched. Leaves ovate-oblong to 

 oblong-lanceolate, rough or pubescent, thick 

 and somewhat rigid, strongly cordate or 

 auriculate-clasping at the broad base, entire, 

 acute, or the lowest obtuse, 1-3' long, those 

 of the branches much smaller and bract-like, 

 the margins rough-ciliate; heads 1' broad or 

 more, solitary at the ends of the branches; 

 involucre broadly turbinate, its bracts linear- 

 oblong, finely pubescent or scabrous and 

 somewhat glandular, imbricated in several 

 series, their green acute tips spreading; rays 

 20-30, purplish-blue, or deep violet, 4"-6 ' 

 long ; pappus .tawny ; achenes pubescent. 



In dry, open places, Maine to northern New 

 York. Minnesota. Florida, Louisiana and Texas. 

 Reported from Canada. Races differ in leaf- 

 form and pubescence. Aug.-Oct. 



