Order 10.— COMPOSIT^E. 427 



Bcales in 5 or 6 series, closely imbricated ; raya longer than the invol. ; ach. qldth 

 rims. — Swamps, Pla! (Chapipan.) A curious Aster, very slender, -with large iids., 

 20 to 30-rayed, spreading 2', purple. 



47 A. linifolius L. Sea Aster. St. paniculate, much branched from the base ; 

 Ivs. long, linear, very acute, the uppermost subulate ; invol. eyiindrio, with subu- 

 late scales in about 3 rows ; rays minute, in two series, scarcely exserted. — An 

 annual species, found in salt marshes, Mass. to Car. St. 12 to 18' high, very 

 smooth, thick, reddish. Lvs. smooth, sessile. The plant is very branching, with 

 numerous small hds., almost discoid from the shortness of the rays. Aug. 



48 A. subnldtus Mx. Annual ; slender, much branched, glabrous ; branches 

 corymbed, slender ; hs. linear-subulate, scabrous, long-linear below ; scales lance- 

 linear, acute, in 2 or .B series ; rays numerous, narrow, longer than the disk, in one 

 row. — Damp grounds, S. Gar. to Pla. Sts. 1 to 3f high. Hds. small, with about 

 20 blue rays longer than the disk. Sept., Oct. (A. divaricatus Nutt.) 



■3. :^xiLis. Taller, with fewer branches, corymbed ; hds. racemed or solitary. 

 Rays pale purple. — Columbus, Ga. (A. exilis Ell.) Height 2 to 4f. 



19. DIPLOPAP'PUS, Cass. Double-bristled Aster. (Gv. Sc-rrXoog. 

 double, ndmrog, pappus.) Heads many-flowered ; ray-flowers about 

 12, $ ; disk-flowers ^ ; involucre imbricate, scales narrow, destitute of 

 green tips ; receptacle flat, subalveolate ; pappus double, the exterior 

 very short (about i" long), interior copious, capillary ; achenia com- 

 pressed. — 2f Lvs. entire, alternate. Kays cyanic. Disk yellow. 



§ Rays violet. Aclienia silky. Bristles of the inner pappus alike No. 1 



§ Kays whitish. Some of the longer bristles clavellate. — Ach. smootbish Nos. 2, -9 



—Ach. villous. No. 4 



1 D. linariifolius Hook. St. straight, roughish ; branches 1-flowered, fastigi- 

 ate ; scales imbricate, carinate, as long as the disk ; lvs. linear, entire, 1- veined, 

 mucronate, carinate, rough, rigid, those of the branches recurved. — A handsome 

 species, in dry woods, along streams, XT. S. and Can. Stems subsimple, purplish, 

 about a foot high. Leaves numerous, obtuse, with a small, mucronate point, shin- 

 ing- above. Branchlets near the top, leafy, each with one rather largo and showy, 

 violet-colored head. Aug., Sept. (Aster, L.) 



2 D. tinibell^tus Hook. St. smooth, straight, simple ; hds. numerous, in a level 

 corymb ; lvs. long, lanceolate, smooth, acuminate at each end, rough on the mar- 

 gin ; invol. scales obtusely lanceolate ; ach. pubescent in lines. — Low grounds, river 

 banks, fields, N. Eng. to -La. St. 3 to 4f high (in dry fields but 1 to 2f) pur- 

 plish, channeled, branching at top into a large, level-topped, compound corymb. 

 Lvs. narrow, entire, 4 to 6' in letigth, those of the branchlets smaller. Rays about 

 12, white. Disk yellow. Aug., Sept. (A. amygdalinus Mx. A. umbeUatus Ait.) 



/3. AMTGDALiNua St. roughisli above, green ; branches of the corymb divari- 

 cate ; lvs. broader. — Lower and less elegant than variety a. Common. 



3 D. comifSlius Less. St. smooth below, scabrous and slightly paniculate 

 above, few-flowered ; lvs. elliplioai, thin, long-acuminate at both ends, entire, with 

 scattered hairs, rough-edged, invol. scales imbricate, shorter than the disk, obtuse ; 

 ach. glabrous. — Grows in woods N. and M. States. Whole plant nearly smooth, 

 erect, 1 to 2f high. Lvs. paler beneath, on very short stalks or sessile. Els. few, 

 large ; outer scales very short. Rays about 10, white. Jl., Aug. (Aster, Muhl.) 



4 D. obovdtus Torr. & Gr. Cinerous-pubescent, corymbous above ; lvs. oblong- 

 obovate or elliptical, acute, sessile or the lower or short petioles, tomentous be- 

 neath; scales loose, linear-siibulate, acute, in about 3 rows, downy, rusty yellow; 

 ach. silky-villous. — Damp shades, S. Car. to Pla. Height 2 to 3£ Lvs. longer 

 than the internodes (2 to 3'), rarely with a few teeth. Invol. 'broadly obconic. 

 Rays narrow, white, spreading IJ'. Pappus rusty white. Sept., Oct. (Aster, BU.) 



20. ERIG'ERON, L. Flea-bane. White-weed. (Gr. rjp, the spring, 

 •yepuv, old man ; because it is soon hoary.) Heads many-flowered, sub- 

 Jiemispherical ; ray-flowers ? , very numerous (40 to 200), narrow, lin- 

 ear : flowers of the disk ^ ; receptacle flat, naked ; scales of the invo- 



