372 COMPOSITiE. Artemisia. 



++++•!-+++ Heads comparatively small (1 to 3 lines hfgh and broad), variouslj' paniculate, 

 12-man\'-flovvered : flowers i;labrous : herbs, or occu:<ionally suffnitescent at base, mostly whit- 

 ened (at least when young and on the lower face of the leaves) with cottony tomentum. 



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

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



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

 white-tomcntose beneath, lanceolate or uppermost linear, all sei-rate with .sharp narrow teeth, 

 pinuatcly veined, the earliest sometimes pinnately incised : heads rather fevv-tiowered, less 

 than 2 lines long, greenish, iiardly pubescent. — Gen. ii. 142. A. Ludoinciana, var. serrata, 

 Torr. & Gray, 11. ii. 420. — Prairies and low grounds, Illinois to Dakota; first coll. by 

 Nuttall. 



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

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

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

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

 first coll. by Nuttall, or by Lewis & Clarke, if perhaps A. intcgrifulia of Fursh. 



= = Moderately tall or sometimes low: leaves 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. LiUdoviciana, Nutt. A foot to a yard higli, simple or with virgate branches, some- 

 times jjanicuJate, completely and somewhat fiocculently 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 

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

 fiowered. — Torr. & Gray, Fl. ii. 420 (exck var. serrata}; Bess. Revis. Artem. in Linn. xv. 

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

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

 in part, not L. A. Purshiana, Bess. Abrot. 59, & Hook. Fl. i. 323. A. Douglasiana, Bess. 

 1. c., an entire-leaved le,ss white-tomentose Western form. A. Hooheriana, Bess. 1. c. ; 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 Saje of Lewis & Clarke, at least in part. (Adj. Mex.) 



b. Involucre not lanate (at least when fully developed), from pilose-pubescent or minutely cauescent 

 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 pinnatifid or trifid ■ heads very 

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

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

 490; Less, 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. & Gray, Fl. ii. 421. A. Ludociciana, in part, Gray, PI. Wright, ii. 98. 

 A. cuneifoiia? & A. Lindheimeriana, Scheele in Linn. xxii. 162, 163. A. Ludoiiciana, \a.r. 

 Mexicana, forma tenuifolia. Gray, PI. Wright, ii. 98, from New Mexico, &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. (Mugwort.) Paniculately branched : leaves white Avith cottony tomen- 

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

 and laciiiiatc, and the lobes lanceolate or coarser ; upper sometimes linear : heads numerous 

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

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

 Gr.T.y, Fl. I.e., excl. var. Mexicana. — The common European form is apparently indige- 

 nous at Hudson's Bay, &c., and is naturalized in Canada {A. Indica, Canadensis, Bess, in 

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



