1214 CARDUACEAE 



19. Aster sagittifblius Willd. Stem rather slender, 6-15 dm. high, strict, glabrous, 

 or sparingly pubescent above, the intiorescence tall and paniculate with ascending branches: 

 leaf-blades thin, glabrous above or but slightly roughened, usually glabrate beneath, those 

 of the basal and lower cauline leaves ovate-lanceolate to lanceolate, with cordate or rarely 

 sagittate base, sharply serrate, acuminate, 7-15 cm. long, with slender naked or narrowly 

 margined petioles ; blades of the upper cauline leaves lanceolate, sessile, or on short and 

 usually margined petioles, serrate or entire, those of the branches very much smaller, linear- 

 subulate : heads 16-20 mm. broad, numerous, crowded, racemose : involucre turbinate ; 

 bracts linear-subulate, glabrous or nearly so, their tips green and slightly spreading : ray- 

 flowers 10-15; ligules light blue or purplish, 6-8 mm. long: pappus whitish. Resembles 

 A. cordifolius L. ; but its bracts narrower, subulate-acuminate, and its inflorescence almost 

 without leafiness, the axile leaves being reduced, narrowed and stringy rather than folia- 

 ceous. 



In drj' soil, New Brunswick to North Dakota, North Carolina, Tennessee and Kansas, Late sum 

 mer and fall. — Adcr sagittifoUus dissitiflorus Burgess, differs from the typical form of the species in its 

 broader looser pyramidal inflorescence, the somewhat larger and loiiger-peduncled heads, the leaf- 

 blades less serrate, often none cordate. New York to Florida, Mississippi and Oklahoma. 



20. Aster plumarius Burgess. Plants about 3 dm. high, chiefly composed of the 

 dense plume-like violet inflorescence : stem smooth, zigzag : leaf-blades very smooth and 

 firm, thickish, chiefly lanceolate-acuminate and slit-serrate, inclined to be strongly falcate 

 at apex and unequal at the slightly cordate broadish base, measuring 7 x 1.5 cm. or less ; 

 veins strongly incurved ; petioles narrow-margined ; lower axile leaves conspicuous, but 

 rapidly diminished, soon becoming narrowly falcate-lanceolate and entire, sessile by a taper 

 subcuneate base : inflorescence otherwise naked, ovate-lanceolate in outline : bracts narrow, 

 acute, their distinct enlarged green tips chiefly spatulate. Resembles a dwarf A. sagiiti- 



folius, but differs in leaves, bract-tijjs, absence of bracteoles^ etc. 



On mountain tops. North Carolina, chiefly on balds at 1500-1550 m. Fall. Plume Aster. 



21. Aster hirt611u3 Lindl. Plant cinereous-green, finely tomentulose, profusely 

 branched and racemose-panicled : stem 6 dm. high or more ; leaf-blades very rough and 

 dull dark green above, soft-hairy and pale beneath, thinnish ; leaf-blades cordate-ovate in 

 type, crenate-serrate in the middle, 4x3 cm. or less ; leaf-form varying to cordate-orbicular 

 and obtuse below, and oblong-acute above ; axiles rounded, oval or lance-elliptic, minute, 

 sessile ; rameals oval, remotish, thin, spreading or deflexed ; similar oval leaves clothe 

 sprouts in the axils : inflorescence forming half of the plant or more, repeatedly ramuli- 

 ferous, with long pedicels (often 3 cm. ) which grow closer and shorter at the summit : 

 heads 2.5 cm. broad : rays about 16, pale purplish, soon becoming whitish : disks soon deep 

 purple : bracts linear-subulate, rather loose, continued in similar bractlets down the pedi- 

 cels ; the faint green tips hardly at all enlarged. 



On plains or prairies, Missouri and Kansas to Texas. Fall. 



22. Aster Drummdndii Lindl. Stem 6-15 dm. high, usually stout, finely and 

 densely canescent : leaf-blades mostly thin, ovate or ovate-lanceolate, sharply toothed, 5-10 

 cm. long, acuminate, rough above, canescent beneath, those of the basal and lower cauline 

 leaves with cordate sinus, and slender naked petioles, those of the upper cauline cordate 

 or rounded at the base, usually on margined petioles, those of the branches chiefly sessile, 

 entire and lanceolate, much smaller : heads 12-25 mm. broad, numerous or crowded on the 

 racemose branches : involucre turbinate ; bracts linear, slightly pubescent, acute or some- 

 what acuminate, their green tips appressed : ray-flowers 8-15 ; ligules purplish blue, 6-8 

 mm. long : pappus whitish. Resembles A. cordifolius L. ; but rougher, more hairy, and 

 decidedly gray. 



In dry soil ; borders of woods and prairies, Ohio to Minnesota, Kansas, Arkansas and Texas. Fall. 



23. Aster Texanus Burgess. Plants but slightly pubescent, with long lax foliolose 

 branches : stem glabrate : leaves roughened and dull above, pale and somewhat cinereous 

 beneath, prevailingly similar in size, shape and slender petiole ; leaf-form of oval-acute 

 type with deep narrow sinus, regularly crenate-serrate to the obtusely-acute apex, 5x4 cm. 

 or less ; radicals oval ; upper-cauline leaf-blades smaller, truncate at base into a narrow 

 strap-like wing ; the uppermost sessile, very small and numerous, ovate or narrowly ellip- 

 tical, so continuing throughout the inflorescence : heads small, 0.5 cm. high, subracemosely 

 long-pedicelled on the slender stem or its branches : bracts somewhat lax, smoothish, lin- 

 ear-acute, the green tips narrowly elliptic : achenes often pubescent. Confused with A. 

 Drummondii ; but its heads scattered, not massed, its leaf-form different, broader, smaller 

 and non-acuminate, its marginal teeth stronger, sinus deep and narrow, its leaves less rough 

 and thick. 



In thickets, Louisiana and Texas. Fall. 



24. Aster trigdnicus Burgess. Plants profusely branched, with rigid glabrate brown- 

 ish stems and long flagellate ascending branches, which are closely short-branched or are 



