coMPosiTAE. (composite I^'AMILY) 569 



tomentose, usuallymuch branched, 3-12 dm.ihigh: leaves lanceolate or oblong, 

 3-7 cm. longj 4-12 mm. wide, entire or the lower somewhat toothed, iwhlts- 

 tomentose on both sides, acute or acuminate, sessile or the lower narrowed 

 into short petioles: heads numerous, erect, spicate-paniculate, above 3 mm. 

 broad; involucre oblong, tomentose. .{Aj-rhizomaia A. Nels. Bull. Torr. Bot. 

 Club 27: 34. 1900; A. pudicaRydh. 1. c. 32: 130; A. pabularis Rydb. 1. c.,33: 

 157; probably A. candicans and A.ifloccosaB,ydh. 1. c. 24::'296; .A. Purshiana 

 Bess.)— From the Missouri river to the Pacific. This as well as A. ludovidana 

 includes a multitude of forms impossible of discrimination. Some of theimore 

 important ones that have received specific names are indicated and a few are 

 given varietal rank. Leaf ■ outline and iacision are wholly valueless as diag- 

 nostic characters, since all possible gradations occm' in both groups. ■ 



15a. Artemisia gnaphalodes diversifolia A. Nels. Many or most of the 

 leaves deeply pinnately cleft into narrow lobes. (A. diversifolia Rydb. 1. c. 

 28: 20. 1901.)— Colorado to Montana. - 



16. Artemisia ludoviciana Nutt.l. c.^ Perennial, ascending or erect, lower 

 than the preceding, 3-5 dm. high, brariched; stem somewhat tomentose: leaves 

 oblanceolate or somewhat cuneate in outline, 2-5 cm. long, densely whiter 

 tomentose beneath; floccose but greener above, deeply 3-7-lobed with lanceo- 

 late lobes, or the upper entire: heads very small and ! numerous, somewhat 

 nodding; involucre oblong-campanulatey tomentose, but less so than in the 

 preceding. {A. Underwoodii and A. Brittonii Rydb: 1. c. 32: 129; A. latiloba 

 Rydb. Mem. N. Y. Bot. Gard. 1: 429. 1900.)— In the' western half of North 

 America. 



17. Artemisia mezicana Willd. 'Spreng. Syst. 3: 490: 1825. iPanieulately 

 branched, 4-10 dm. high, less tomentose: leaves narrow-lanceolate to Unear, 

 commonly attenuate, some 3-5-cleft or parted; radical cuneate, incisely 

 pinnatifid or trifid: heads very numerous in an ample loose panicle, many- 

 pedicellate, '3-4 mm. long; involucre arachnoid-canescent or glabrate, largely 

 scarious. — ^From Nevada through the southern part of our range to Texas.i 



17a. Artemisia mexicana silvicola (Osterh.) A. Nels. "Distinguished by 

 its fewer and larger leaves, the more lax inflorescence, and 'larger heads.'' 

 These differences probably due to the moisture and shade of its habitat. 

 {A. silvicola Osterh. 1. c. 28: 645.) — Northern Colorado^ on shaded stream 

 banks. •' ■■.)•., ,„.,',, i ■,, 



176. Artemisia mezicaiia Bakeri (Greene) A. Nels. A slender form with 

 short, linear, entire leaves on the branchlets and the lower withremote pinnate 

 segments: the whole plant greenish but hghtly araclmoid-canescent. {A. 

 Bafceri Greene, PI. Baker. 3: 31. 1901. )-^afion of the Gunnison, Colorado. ■ 



18. Artemisia paticice|>hala A. Nels. 1. c:'35. Tuftfed on woody rhizomes, 

 thinly but permanently silvery-tomentose throughout; stems numerous, leafy 

 to the summit, erect, simple or sp'arihgly branched, 2^ dm. high:i leaves 4-8 

 cm. long, entire' or deeply pinhatifid; Unear to lanceolate; some with abroad, 

 3-5-cleft apex, nearly all with a narrowed, petiole-like base: heads few> 

 raeemosely disposed on the main stem and its slender branches (if any), rather 

 large, sessile or short-pediceled, broadly campanulate, about 5 mm. in diam- ■ 

 eter (40-60-flowered) ; involucral bracts oval or ovate, scarious-margined: the 

 pistillate flowers few, very slender, with linear-clavate styles. (^A. gracilenta 

 A. Nels. 1. c.) — Sandy banks near Yellowstone Lake. 



19. Artemisia franserioides Grefene, Bull. Torr. Bot. Club 10: 42. 1883. 

 Glabrous except on the lower face of the leaves, or minutely and obseiu-ely 

 puberulent; stem rather stout, 4-8 dm. high: leaves comparatively ample, 

 green above, pale and cinereous beneath;' the lower bipinnately and the upper 

 simply pinnately parted into lanceolate-oblong obtuse,, entire or 2-3-cleft 

 divisions aiid lobes: heads numerous, loosely racemose on the branches of the 

 leafy elongated panicle, 4-6 mm. broad. — ^Mountains of Colorado, New Mex- 

 ico, and Arizona. , ; 



20. Artemisia discolor Dougl. in Herb. Hook.; DC. Prodr. 6: 109. 1837. 

 Stems mostly slender, 2-3 dm. high, from a slender lignescent caudex: leaves 

 1-2-pinnately parted into narrow linear or lanceolate-entire or sparingly 



