Genus 88.] 



THISTLE FAMILY 



16. Artemisia serrata Nutt. 



Saw-leaf Mugwort. (Fig. 4013.) 

 Artemisia serrata Nutt. Gen. 2: 142. 1818. 



Perennial; stem stout, tomentose or be- 

 coming glabrous, much branched, 5-io 

 high. Leaves lanceolate, 2 / -6 / long, .3"- 

 12" wide, densely white-tomentose beneath, 

 dark green and glabrous above, acuminate 

 at the apex, narrowed to a sessile base, or 

 the lowest petioled, sharply serrate or in- 

 cised, or the upper entire; heads very nu- 

 merous, greenish, erect, about l}^ // broad, 

 sessile or short-peduncled in panicled spikes 

 or racemes; involucre canescent, its bracts 

 oblong, obtuse, or the outer ones lanceolate; 

 receptacle naked; central flowers fertile. 



Prairies, Illinois to Minnesota and Dakota. 

 Introduced on the Mohawk River, near Sche- 

 nectady, N. Y. Aug. -Oct. 



17. Artemisia longifolia Nutt. 

 Long-leaved Mugwort. (Fig. 4014.) 

 Artemisia longifolia Nutt. Gen. 2: 142. 1818. 



Perennial; stem densely white-tomentose, 

 branched, 2-5 high. Leaves linear or lin- 

 ear-lanceolate, elongated, entire, a'-s' long, 

 l // ~5 // wide, acuminate, tapering to a sessile 

 base, or the lower petioled, densely white- 

 tomentose on both sides, or becoming green 

 and glabrate above; heads numerous, erect, 

 spicate-paniculate, about 2" broad; involucre 

 tomentose, its bracts oblong, obtuse; recep- 

 tacle naked ; central flowers fertile. 



In dry rocky soil, western Nebraska to Min- 

 nesota, Montana and the Northwest Territory. 

 Aug. -Sept. 



18. Artemisia gnaphalodes Nutt. 



Prairie, Western or Cud-weed 



Mugwort. (Fig. 4015.) 



Artemisia gnaphalodes Nutt. Gen. 2: 143. 1818. 

 Artemisia Ltidoviciana var. gnaphalodes T. & 

 G. Fl. N. A. 2: 420. 1843. 



Perennial, similar to the preceding spe- 

 cies; stem white-tomentose, usually much 

 branched, i-4 high. Leaves lanceolate or 

 oblong, I/-3' long, 2 // -6 // wide, entire, or 

 the lower somewhat toothed, lobed or in- 

 cised, white tomentose on both sides, acute 

 or acuminate, sessile or the lower narrowed 

 into short petioles; heads numerous, erect, 

 spicate-paniculate, above i% ;/ broad; invo- 

 lucre oblong, tomentose; receptacle naked; 

 central flowers fertile. 



On prairies and dry banks, western Ontario 

 and Illinois to British Columbia, south to Mis- 

 souri, Texas, Arizona, Mexico and California. Aug.-Oct 



