320 LXXV. COMPOSITiE. Aster. 



serrate, peliolate ; invol. scales loose, lanceolate. — Low woods, N. and W. States 

 and Can. Stem 2—41' high, dividing into many ascending, rigid branches, with 

 numerous and crowded heads, forming a compound panicle of racemes. Heads 

 small, each with about 12 rays, which are white or with various shades of 

 blue. Leaves becoming smaller above, lanceolate and even linear. Sept. 



8. A. UNDULATUs. Wave-lcaf A?fer. 



St. paniculate, hispid; branches secund, leafy, 1-flowered; Ivs. oblong- 

 cordate, amplexicaul, very entire, hairy, somewhat undulate or crenate-serrate, 

 lower ones ovate, cordate, subserrate, with winged petioles. — Native of dry 

 woods, U. S. Plant rough, about 2f high, with slender branches. Lower 

 leaves on long winged petioles, cordate, acuminate, upper ones becoming nar- 

 row-ovate and clasping. Flowers pale blue, solitary, forming a loose panicle 

 of somewhat one-sided racemes. Aug. Sept. 



9. A. AZUREUs. Lindl. (A. Oolentangiensis. Riddcll.) 



Scabrous ; st. and racemose paniculate branches rigid ; Ivs. lance-ovate, cor- 

 date, slightly serrate, on hairy petioles, middle and upper ones lanceolate and 

 linear, acute at each end, sessile, entire, highest subulate; Arfs. broadly obconic ; 

 scales oblong-linear, acute, appressed. — Woods and prairies, "Western States. 

 Stem about 2f high. Leaves of several forms between the lowest cordate to 

 the small, subulate, numerous lloral ones of the slender branches. Racemes 

 rather remote, panicled, with middle-sized heads. Rays blue. 



10. A. Shortii. Hook. Short's Aster. 



Slender and nearly glabrous, simple or somewhat branched above ; Ivs. 

 lance-ovate, cordate, petiolate, long-acuminate, subentire, upper ones sessile 

 and obtuse at base ; Ms. middle-size, racemose or racemose-paniculate, rather 

 numerous ; invol. broad-campanulate ; scales scarious, close, green-tipped, shorter 

 than the disk flowers. — A distinct and beautiful species, on rocky banks of 

 streams, Ohio ! to Ark. Stem a little flexuous, 2 — tf high. Lower leaves about 

 5' by H', the others successively diminished upwards to the flowers where they 

 are minute. Rays violet blue. 



* * Lower leaves never cordate. Caulinc leaves clasping and cordate or 

 auriculate at base. 



11. A. PATENS. (A. amplexicaulis. Willd.) Spreading Aster. 



St. simple, paniculate above, pubescent ; Ivs. lanceolate, cordate, clasping 

 the stem, acuminate, scabrous on the margin, pubescent; panicle loose, few- 

 flowered ; scales imbricate, lanceolate, lax, the points herbaceous. — Grows in 

 moist grounds. Northern States. Stem 2^3f high, slender, branching above 

 into a loose, terminal panicle. Leaves large, (3—6' long) on the stem, becom- 

 ing small and bracteate on the branches. Heads solitary on the ends of the 

 leafy branchlets, large, with 20 — 30 violet-colored rays. Aug. — Nov. 



12. A. LiBVis. (A. mutabilis. Linn. A. amplexicaulis. Muhl.) Smooth Aster. 

 Very smooth ; st. angular ; branches simple, 1-flowered ; Ivs. subamplexi- 



caul, remote, oblong, entire, .shining, radical ones subserrate; invol. closely 

 imbricate, the scales broadly-linear, rigid, thickened and herbaceous at the 

 apex. — A very smooth and beautiful species, 2 — 3f high, growing in low grounds. 

 Stem polished, green, often somewhat glaucous. Leaves rather fleshy, broadest 

 at base, the lower ones tapering to a winged petiole. Flowers large and showy, 

 with numerous rays of a fine blue, becoming purple. Sept. — Nov. 



/?. levigatus. (A. Isevigatus. Willd.) Lvs. long, linear-lanceolate. 



y. cyanevs. (A. cyaneus. Ph.) (S/. and ^rs. con.spicuously glaucous. — These 

 are beautiful varieties, especially the latter, which is perhaps the most beauti- 

 ful of all the aster.s, 



13. A. coNciNNus. Willd., not of Nees. Elegant Aster. 



St. simple, paniculate at the summit, pubescent; lvs. lanceolate and lance- 

 linear, narrowed and clasping at the base, remotely serrate, upper ones entire; 

 invol. closely imbricate, scales green at the tip. — Woods, Northern States! 

 A slender species, I— 2f high. Branches of the panicle rather short and re- 

 mote. Leaves 3 — 5' long, acuminate, varying from i — 1' in width, smooth ex- 



