COMPOSITAE (composite FAMILY) 849 



RPuerally glabrous, green; root perennial. — Calcareous rooks, Nfd. to B. C, s. 

 to n. N. E., Minn., etc. (Eu.) 



3. A. borealis Pall. Similar, 1-3 dm. high ; lower leaves 1-2-ternately 

 divided ; upper linear, mostly entire ; heads fewer, subracemose ; involucre 

 pilose or glabrate, brownish ; root perennial. — Arctic regions, s. to the serpen- 

 tine mts. of e. Que., Keweenaw Point, Mich., Col., and "Wash. (Asia.) 



* * Leaves enkre or some 3-cleft. 



4. A. dracunculoides Pursh. Tall (0.5-1.5 m.), somewhat woody at base, 

 slightly hoary or glabrous; leaves narrowly linear and entire or the lower 

 .3-cleft ; heads small and numerous, panicled. — S^ndy banks and prairies, 

 Man. to 111. , Mo., westw. and southwestw. 



5. A. glaiica Pall. Strict, 3-6 dm. high, somewhat woody at base, minutely 

 silky-pubescent or glabrate and glaucous; leaves linear- to oblong-lanceolate; 

 heads as in the preceding. — Prairies, Sask. to Minn, and N. Dak. (Siber.) 



§ 2. Beeeptaele smooth ; flowers all fertile, a few pistillate, the others perfect. 



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

 have occasionally escaped from gardens and become spontaneous, viz. A. 

 Abe6tanum L. (the Southernwood), of strict habit, with 1-2-pinnatifid leaves 

 and pubescent heads ; and A. pr6ceea Willd., with more spreading branches, 

 all the leaves finely 2-pinnatifid, and heads glabrous. 



* Branching perennials, whitened with fine and close-pressed wool ; heads small, 



in leafy panicles. 



6. A. serrata Nutt. Very leafy, 1.5-3 m. high; leaves lanceolate or the 

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

 subcylindric, 4.3 mm. long or less. — 111. to S. Dak.; sparingly naturalized 

 eastw. 



7. A. longifblia Nutt. Stem 0.5-1.5 m. high ; teases linear or linear-lanceo- 

 late, entire, usually glabrate above ; heads subcylindric, canescent, 4-6 mm. long. 

 — Minn, to Neb., and westw. 



8. A. ludoviciana Nutt. (Western Mdgwort, White Sage.) Whitened- 

 woolly throughout ; leaves lanceolate, the upper mostly entire, the lower usually 

 cut-lobed, toothed or pinnatifid, the upper surface sometimes glabrate and 

 green ; heads campanulate, mostly sessile in slender panicles. (Including A. 

 gnaphalodes Nutt.) — Dry banks, Sask. to Mich., 111., Tex., and westw,; locally 

 naturalized eastw. — Very variable. 



9. A. vulgXkis L. (Common MuGwORT.) Tall; leaves mostly glabrous and 

 green above, the lower surface (and the branches) white-woolly, all pinnatifid, 

 with the divisions often cut-lobed, linear-lanceolate ; heads small, in open pani- 

 cles. — Waste places and roadsides, and along streams, e. Que. to Ont. and Pa. 

 (Nat. from Eu.) 



10. A. KANSA.NA Britton. Low, 1-6 dm. high ; leaves finely pinnatifid into 

 linear segments; heads densely woolly, in strict close panicles. — Plains and 

 foot-hills, w. Kan., Col., and N. Mex. ; adventive eastw. 



* * Densely white-tomentose, perennial; heads large, racemose-glomerate ; invo- 



lucral bracts herbaceous. 



11. A. StelleriXna Bess. (Beach W., Dusty Miller, Old Woman.) 

 Stout, 3-6 dm. high, from a creeping base ; leaves obovate or spatulate, pin- 

 natifid, the lobes obtuse. — Sandy sea-beaches, e. Que. to N. J., and shores of 

 Oneida L., N. Y. (Saberer'); commonly cultivated in old gardens, and recently 

 spreading extensively to sandy soil. (Introd. from n. e. Asia.) 



* * * Less branched, biennial or annual, glabrous. 



12. A. biennis Willd. Strict, tall ; lower leaves 2-pinnately parted, the 

 upper pinnatifid ; lobes linear, acute, in the lower leaves cut-toothed ; heads in 

 short axillai'y spikes or clusters, crowded in a slender and glomerate leafy 

 panicle. — Gravelly banks, 0. to Tenn., Mo., and northwestw.; now established 

 eastw. by railroads and in waste places. 



