420 OEDER 70. COMPOSITE. 



very silky ; pappus simple. 2 Herbs with alternate Ivs. and close 

 corymbs. Rays white. 



" S. solidagineus Nees. Smooth; Ivs. linear-oblanceolate, obtuse, entire, sessile, 

 obsoletely 3-veined, rough on the margin ; corymb fastigiate ; lids, aggregate, 

 subsessilo, 5-rayed ; scales obtuse, white, with green tips ; pappus white. In 

 woods, Can to La. Very elegant. Sts. clustered, slender, simple, about 2f high. 

 Lvs. smooth, 1 to 2' by 3 to 5". Hds. small (3'' long). Invol oblong. Scales with 

 conspicuous green tips. Rays long, white. JL, Aug. (Aster solidaginoidee MX.) 



2 L. coiryzoides Nees. St. somewhat pubescent, simple, corymbus at top; Ivs- 

 oval-lanceolate, smooth beneath, slightly 3-veined, narrowed "at base, acute, the 

 upper ones sessile, nearly entire, the lower narrowed into the petiole, serrate ; in- 

 vol. cylindrical, the scales oval, obtuse, appressed, slightly reflexed at summit ; 

 rays 5, short, pappus rusty. Common in woods and thickets, Mass to Flor. 

 Stems somewhat 5- angled, 1 2f high. Leaves somewhat fleshy. Ray short, 

 but longer than tho disk, white. July, Aug. (Aster Willd. Conyza aster- 

 oides L.) 



3 S. tortifolius Nees. Grayish-pubescent, roughish, corymbous above; Ivs. 

 short, oblorig-obovate, sessile, twisted to a vertical position, and both sides alike 

 minutely scabrous ; scales regularly imbricated in many rows, tho green tips 

 slightly spreading ; pappus white. Dry woods and barrens, Va. to Fla. and La. 

 Height about 2f, often branched below. Lvs. 8 to 12" long, obtuse or acute. Hds. 

 larger than in the others, about 5" long. Sept., Oct. 



18. AS'TER, L. (Gr. a<m/p, a star ; from the radiated flowers.) Hds. 

 radiate ; involucre oblong, imbricate ; scales loose, often with green 

 tips, the outer spreading; disk flowers tubular, > ; ray flowers $ , in one 

 row, generally few (6 100), lignlate, oblong, 3 -toothed at apex, finally 

 revolute ; receptacle flat, alveolate ; pappus simple, capillary, scabrous*; 

 achenium usually compressed. A large genus of 2 herbs, very abun- 

 dant in the U. S., flowering in late summer and autumn. Lvs. alter- 

 nate. Disk fls. yellow, changing to purple, ray flowers blue, purple or 

 white, never yellow. 



BIOTIA, DC. Scales closely imbricated, slightly tipped with green. lids, corymbous, 



rays6to!5, white or roseate. Lvs. cordate, ]>etiolate, serrate, large Nos. 1,2 



| CALLTASTRUM, T. & G. Scales loosely imbricated, with green spreading tips. Heads 

 corymbous or few, laree, rays 12 to 80, violet. Leaves never cordate, rigid ; pappus 



unequal, rigid, the inner slightly club-shaped. Leaves all or the lower seriate Nos. 35 



Leaves entire Nos. 6, 7 



{ ASTER proper. Scales (variously) imbricated, with green tips or wholly green. Hds. 

 paniculate or raceuions. Pappus soft, equal (none club-shaped), (a) 

 a Leaves clasping with a cordate or auriculate base, (b) 

 a Leaves sessile or petiolate, none of them cordate or auricnlate. (c) 



a Leaves petiolate, the lower cordate, evidently serrate Nos. 8, 9 



entire, or obscurely serrate Nos. 10^12 



b Leaves entire, very small (1 to 3" Ions), erect or reflexed Nos. 18, 14 



middle size (1 to 3' Ions), Achenia silky Nos. 1517 



Achcnia smooth Nos. 20, 85 



b Leaves serrate (more or less). Scales spreading, equal, in 2 rows. No. 18 



Scales imbricated, in 3 to 5 rows Nos. 19 21 



C Leaves silky on both sides alike. Pappus tawny Nos. 22, 28 



C Leaves not silky. Involucre closely imbricated, (d) 



Involucre squarrous, tlio scales spreading, (e) 



d Leaves all entire. Scales of the involucre obtuse Nos. 24,25 



Scales acute or mucronate Nos. 2fi 28 



d Leaves (lower) sharply serrate. Heads larger (4 to 6" long) Nos. 29, 30 



Heads small (2 to 3" long) Nos. 81, 32 



e Scales obtnse, in several rows, unequal. Leaves also obtuse. .Nos. 33, 34 



6 Scales acute, in several rows, unequal Pappus tawny Nos. 3587 



Pappus bright Nos. 8840 



e Scales acute, in one row. equal. Leaves linear. Heads solitary.. -No. 41 

 $ SCAKIOS^!. Scales (variously) imbricated, with scarious margins and destitute of 

 green tips, (f) 



f Leaves lanceolate broadly or narrowly. Scales rather obtuse Nos. 42 44 



Leaves subulate or linear. Scales very acute. Heads large, few Nos. 45, 40 



Heads small, many Nos. 47, 4d 



