GENUS 31. 



THISTLE FAMILY. 



419 



31. Aster puniceus L. Red-stalk or 

 Purple-stem Aster. Fig. 4312. 



Aster puniceus L. Sp, PI. 875. 1753- 



Stem usually stout, reddish, corymbosely or 

 racemosely branched above, hispid with rigid 

 hairs to glabrous, 3-8 high. Leaves lanceolate 

 to oblong-lanceolate, acuminate, sessile and clasp- 

 ing by a broad or narrowed base, sharply serrate, 

 or entire, usually very rough above, pubescent on 

 the midrib or glabrous beneath, 3'-6' long, i'-ii' 

 wide; heads generally numerous, i'-ii' broad; 

 involucre nearly hemispheric, its bracts linear or 

 oblong, attenuate, imbricated in about 2 series, 

 glabrous or ciliate, green, loose, spreading, nearly 

 equal, sometimes broadened ; rays 20-40, violet- 

 purple or pale (rarely white), 5"-?" long, showy; 

 pappus nearly white; achenes pubescent. 



In swamps, Newfoundland to Ontario, Manitoba, 

 Minnesota, Georgia, Tennessee, Ohio and Michigan. 

 Races differ in pubescence, leaf-form and leaf-serra- 

 tion. Early purple aster. Swan-weed. Cocash. Meadow- 

 scabish. July-Nov. 



32. Aster tardiflorus L. Northeastern 

 Aster. Fig. 4313. 



Aster lardiflorus L. Sp. PI. Ed. 2, 1231. 1763. 

 Aster patulus Lam. Encycl. i : 308. 1783. 



Stem glabrous, slightly pubescent, or villous, co- 

 rymbosely branched near the summit, i-3 high. 

 Leaves lanceolate, oblong-lanceolate, or ovate-lan- 

 ceolate, serrate with low teeth, or some of them 

 entfre, acuminate at the apex, narrowed into a 

 slightly clasping base, or the lower into winged 

 petioles, glabrous or nearly so on both sides, rough- 

 ish-margined, 3'-6' long, 4"-io" wide ; heads about 

 i' broad, not very numerous, involucre hemispheric, 

 its bracts often 6" long, acute, somewhat unequal ; 

 rays 20-30, violet; pappus nearly white; achenes 

 pubescent. 



Along streams, New Brunswick to Pennsylvania. 

 Aug.-Oct. 



33. Aster prenanthoides Muhl. Crooked- 

 stem Aster. Fig. 4314. 



A. prenanthoides Muhl. ; Willd. Sp. PI. 3 : 2046. 1804. 



Aster prenanthoides porrectifolius Porter, Mem. Torr. 

 Club 5 : 326. 1894. 



Stem glabrous, or pubescent in lines above, 

 flexuous, much branched, i-2 high. Leaves 

 thin, oblong to ovate-lanceolate, or lanceolate, 

 sharply and coarsely serrate, scabrous above, gla- 

 brous or nearly so beneath, 3'-8' long, g"-iS" 

 wide, acuminate at the apex, abruptly narrowed 

 below into a broad margined entire petiole, the 

 base auriculate-clasping ; heads usually numerous, 

 i' broad or more; involucre hemispheric, its bracts 

 linear, acute, green, spreading, imbricated in 3 or 

 4 series, the outer shorter ; rays 20-30, violet, 

 4"-6" long; pappus tawny; achenes pubescent. 



In moist soil, Massachusetts to Minnesota, Vir- 

 ginia, Kentucky and Iowa. Aug.-Oct. 



Aster schistosus Steele, of West Virginia, is in- 

 termediate in characters between this species and A. Lowrieanus Porter, and may be a hybrid. 



