372 COMPOSITiE. Artemisia. 



++++++++ Heads comparatively small (1 to 3 lines high and broad), variously paniculate, 

 12-many-flowered : flouers glabrous: herbs, or occasionally suffrutescent at base, mostly wliit- 

 ened (at least when 3'oung and on the lower face of the leaves) with cottony tonieutum. 



= Tall, with numerous amply paniculate heads, strict stems, and undivided elongated-lanceolate 

 or linear leaves (the lowest sometimes cleft), 3 to 7 inches long: involucre oblong. 



A ■ serrata, Nutt. Stems 6 to 9 feet high, very leafy : leaves green and glabrous above, 

 white-tomeiitose beneath, lanceolate or uppermost linear, all serrate with sharp narrow teeth, 

 pinuately veined, the earliest sometimes pinuately incised : heads rather few-tiowered, less 

 than 2 lines long, greenish, hardly pubescent. — Gen. ii. 143. A. Liuhwiciumi, var. serrata, 

 Torr. & Gray, ¥\. ii. 420. — Prairies and low grounds,- Illinois to Dakota; first coll. by 

 Nuttall. 



A., longifolia, Nutt. 1. c. Stem 2 to 5 feet high: leaves entire, at first tomentulose, but 

 usually glabrate above, white tomentose beneath, linear or linear-lanceolate (1 to 5 lines 

 wide), entire ; veins obsolete : heads usually canescent, 2 or 3 lines long. — Torr. & Gray, Fl. 

 ii. 419, not Bess. Rocky banks. Minnesota and Nebraska to Saskatchewan and Montana; 

 first coll. by Nuttall, or by Lewis & Clarke, if perhaps A. inte<jri/olia of Pursh. 



= == Moderately tall or sometimes low: ?eaves various, more or less cleft or divided, or when 

 entire comparatively short, not filiform or very narrowly linear. Species of very difficult dis- 

 crimination. 



a. Involucre canescently lanate-tomentose. 



A. Ludoviciana, Nutt. A foot to a yard high, simple or with virgate branches, some- 

 times paniculate, completely and somewhat flocculeutly white-tomentose, or upper face of 

 leaves sometimes early glabrate and green : leaves from linear-lanceolate to oblong, some- 

 times nearly all undivided and entire; commonly the lower with a few coarse teeth or 

 incisions, or 2-3-cleft, or irregularly ■3-5-parted into lanceolate or linear entire lobes: heads 

 glomerately paniculate, not over 2 lines long; involucre campanulate or in fruit ovoid, 12-20- 

 flowered. — Torr. & Gray, Fl. ii. 420 (excl. var. serrata); Bess. Revis. Artem. in Linn. xv. 

 104; Gray, Bot. Calif, i. 404. A. Ludoviciana (with incised or subpinnatifid leaves) &, A. 

 gnaplialocles (with undivided leaves), Nutt. Gen. ii. 143. A. interjrifolia, Pursh, 1. c, at least 

 in Y>art, not L. A. Purshiana, Bess. Abrot. 59, & Hook. Fl. i. 323. A. Dotiglnsiana, Bess. 

 I.e., an entire-leaved less white-tomentose Western form. A. Hooleriana, Bess. I.e. ; the 

 plant taken to be this, of " Rocky Mts., Saskatchewan, &c., Drummond ," in herb. Hook., but 

 not ticketed, is a tall and large-leaved form. — Plains and banks, Saskatchewan to Texas, 

 east to Illinois and Upper Michigan, and west to Brit. Columbia, California, and Arizona. 

 The Wild Sage of Lewis & Clarke, at least in part. (Adj. Mex. ) 



b. Involucre not lanate (at least when f ullj' developed), from pilose-piibescent or minutely canescent 

 to glabrate or glabrous: divisions of the leaves broad or narrow, but not filiform. 



A . Mexicana, Willd. Intermediate between preceding and following, paniculately 

 branched, 2 to 4 feet high, less tomentose : leaves narrow-lanceolate to linear, commonly at- 

 tenuate, some 3-5-cleft or parted ; radical cuneate, incisely pinuatifid or trifid • heads very 

 numerous in an ample loose panicle, many pedicellate, 1 to 2 lines long : involucre campanu- 

 late, arachuoid-canescent or glabrate, largely scarious, 10-20-flowered. — Spreng. Syst. iii. 

 490 ; Le.ss. in Linn. v. 163 ; DC. Prodr. vi. 114 ; Bess. Revis. 1. c. 106. A. Indica, var. Mexi^ 

 cana, Bess. Abrot. 56. A. vulgaris, var. Americana, Bess, in Linn. xv. 105. A. vulgaris, 

 var. Mexicana, Torr. & Gra}^ Fl. ii. 421. A. Ludoviciana, in part. Gray, PI. Wright, ii. 98. 

 A. cuneifolia? & A. Lindlieimeriana, Scheele in Linn. xxii. 162, 163. A. I^udoriciana, var. 

 Mexicana, forma tenuifolin. Gray, PI. Wright, ii. 98, from New ]\Iexico, &c., is a very narrow- 

 leaved variety, with strict panicle. — Dry plains, Arkansas and Texas to Arizona and S. W. 

 Nevada. (Mex.) 



A . vulgaris, L. (Mug wort.) Paniculately branched : leaves white with cottony tomen- 

 tum beneath, green and soon glabrate or glabrous above, usually bipinnatcly cleft or parted 

 and laciniate, and the lobes lanceolate or coarser; up])er sometimes linear : heads numerous 

 and glomerate-paniculate, 2 lines long : involucre mostly oblong-camjianulate, .scarious, 

 sparingly arachnoid but usually glabrate. — Michx. Fl. ii. 128; Pursli, Fl. ii. 522; Torr. & 

 Gray, Fl. 1. c., excl. var. Mexicana. — The common European form is a))parently indige- 

 nous at Hudson's Bay, &c., and is naturalized in Canada (^4. Indica, Canadensis, Bess, in 

 Hook. Fl.) and Atlantic States. (Eu., Asia.) 



