I 



COMPOSITE. (COMPOSITK FAMILY.) 291 



§ 2. Receptacle, smooth ; Jloicers all fertile, afiir jiistiilate, the others perfect. 



Two cultivated sliruhby species, from Europe, with filiformly divided leaves, 

 ^avc occasionally escaped from gardens and liecome spontaneous, viz., A. Ah- 

 noTiNUM, I>. (the Solthkunwood), of strict lialiit, with leaves 1 - '2-pinnatifid 

 and pubescent lieads, and A. riJ^cEUA, ]>., with more spreading branches, all 

 the leaves finely 2-piunatifid, and heads glabrous. 



* Tall (1-5°) and braiichitiff perennials, icltitened with Jine and close-pressed 

 icool ; heads small, in lea/i/ panicles. 



6. A. serrclta, Nutt. Very leafy, 6-9° high; leaves lanceolate or tlie 

 upper linear, serrate, white-tomentose beueath, green above ; heads greenish, 

 oblong, 2" long or less. — 111. to Dak. 



7. A. longif61ia, Nutt. stem 2-5° high; leaves linear or linear-lanceo- 

 late, entire, usually glabrate above ; heads oblong, cauescent, 2 - 3" long — 

 Minn, to Neb., and westward. 



8. A. Ludovici^na, Nutt. (Western Migwort.) Whitened iroolli/ 

 throughout; leares lanceolate, the u\)\)er most 1 1/ entire, the lower usually cut- 

 lol)ed, toothed or pinnatifid, the U])per surface sometimes glabrate and green ; 

 heads campanulate, mostly sessile iu narrow panicles. — Dry banks, 8ask. to 

 Mich., 111., Tex., and westward. Very variable. 



A. vtloXris, L. (Common Mikjwoht.) f.eaves mostli/ c/lahrous and 

 nreen above, beneath and the branches white-woolly, all piimatifid, with the 

 divisions often cut-lol)ed, linear-lanceolate; heads snuill in open panicles. — 

 Waste places, near dwellings. (Adv. from Eu.) 



« * Denselji white-tomentose perennial: heads large, racemose-glomerate. 

 9 A. Stelleriana, Be.ss. Stout, 1-2° high, from a creeping base; 

 leaves obovate or spatulate, pinnatifid, the lobes obtuse. — Sandy sea-beaches, 

 E. Mass. ; locally nat. from N. E. Asia^ 



* * * Less branched (1 -3°), biennial or annual, glabrous. 



10. A. biennis, Willd. Strict, 1 -3° high; lower leaves twice-pinnately 

 parted, tlie upper pinnatifid; lobes linear, acute, in the lower leaves cut- 

 toothed ; heads in sliort axillary spikes or clusters, crowded in a narrow and 

 glomerate leafy panicle. — Gravelly banks, Ohio toTenn., Mo., and northwest- 

 ward , rapidly extending eastward by railroad to Buffalo, I'liiladelphia, etc. 



A. Annua, L. Tall, much branched ; leaves 2-pinnately divided, the oblong 

 segments deeplv pinnatifid; lieads small, in a loose ample panicle. — Ind. to 

 Kan. (Nat. from Old World.) 



§ 3. Receptacle hain/ ; flowers all fertile, the marginal ones pistillate. 



A. Absinthhm, L. (Wormwood.) Rather shrubby (2-3° high), silky- 

 hoary ; leaves 2-3-pinnately parted, lobes lanceolate; lieads hemisjiherical, 

 panicled. — Roadsides, escaped from gardens. (Adv. from Eu.) 



1 1. A. frigida, Willd. Low (6-20' high), in tufts, slightly woody at the 

 base, white-silky ; leaves pinnately parted and 3 - 5-cleft, the divisions narrow- 

 linear; heads globose, racemose. — Dry hills and rocks, Sask. to Miun., W. 

 Tex., and westward 



72. TUSSILAGO, Tourn. Coltsfoot. 



Head many-flowered, ray-flowers in several rows, narrowly ligulate, pistil- 

 late, fertile ; disk-flowers with undivided style, sterile. Involucre nearly simple. 

 Receptacle flat. Achenes cylindrical-oblong; pappus copious, soft and capil- 



