420 



COMPOSITAE. 



VOL. III. 



34. Aster laevis L. Smooth Aster. 

 Fig- 43 1 5- 



Aster laevis L. Sp. PI. 876. 1753. 



Aster laevis ainplifolius Porter, Mem. Torr. Club 5 : 



324. 1894. 

 Aster laevis potomacensis Burgess ; Britt. & Brown, 



111. Fl. 3: 369. 1898. 



Stem usually stout, glabrous, often glaucous, 

 2-4 high, branched or simple. Leaves thick, en- 

 tire, or serrate, glabrous, slightly rough-margined, 

 the upper all sessile and usually cordate-clasping, 

 lanceolate, oblong-lanceolate, oblanceolate or 

 ovate, acute or obtusish, i'-4' long, 4"-2 r wide, 

 the basal and lower gradually narrowed into 

 winged petioles, those of the branches often small 

 and bract-like; heads usually numerous, about i' 

 broad ; involucre campanulate, its bracts rigid, 

 acute, appressed, green-tipped, imbricated in sev- 

 eral series; rays 15-30, blue or violet; pappus 

 tawny; achenes glabrous or nearly so. 



Usually in dry soil, Maine to Ontario, Virginia, 

 Alabama, Louisiana, Saskatchewan, Missouri and 

 Colorado. Races differ in leaf-form. Sept.-Oct. 



35. Aster concinnus Willd. Narrow-leaved 

 Smooth Aster. Fig. 4316. 



Aster concinnus Willd. Enum. 884. 1809. 



Similar to narrow-leaved forms of Aster laevis, 

 and perhaps a race of that species, glabrous, or 

 sparingly pubescent above, not glaucous ; stem 

 paniculately branched, i-3 high. Leaves light 

 green, lanceolate to linear, entire, or sometimes ser- 

 rulate, the upper sessile, somewhat clasping, i'-3' 

 long, the lower and basal ones spatulate, or oblong, 

 narrowed into margined petioles, sometimes coarsely 

 toothed ; heads usually numerous, about 10" broad ; 

 bracts of the involucre with rhomboid acute herba- 

 ceous tips ; rays violet to purple. 



Woodlands, Connecticut to Pennsylvania, Virginia, 

 North Carolina, Missouri and Arkansas. Sept.-Oct. 



36. Aster purpuratus Nees. Southern 

 Smooth Aster. Fig. 4317. 



Aster virgatus Ell. Bot. S. C. & Ga. 2: 353. 1824. Not 



Moench, 1802. 

 A. purpuratus Nees, Gen. & Sp. Ast. 118. 1832. 



Stem slender, glabrous, simple, or branched 

 above, ii-3 high, the branches sometimes pu- 

 berulent. Leaves firm, glabrous, dark green, en- 

 tire, the upper sessile and clasping at the base, 

 elongated-lanceolate or linear-lanceolate, acumi- 

 nate, 2'-6' long, 2"-4" wide, the lower and basal 

 ones petioled, oblong-lanceolate, obtusish, those 

 of the branches very small ; heads rather few, 

 loosely paniculate, 8"-i2" broad; involucre cam- 

 panulate to turbinate, its bracts coriaceous, linear, 

 appressed, green-tipped, acute, imbricated in sev- 

 eral series, the outer shorter; rays 5-10, blue or 

 violet, 3"-5" long, pappus tawny ; achenes glabrous. 



Virginia and West Virginia to Georgia and Texas. 

 Aug.- Sept. 



