Genus 94. 



THISTLE FAMILY. 



5 2 9 



18. Artemisia ludoviciana Nutt. Dark- 

 leaved Mugwort. Fig. 4588. 



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



Perennial, 2-4 high ; stem woolly, branched 

 above. Leaves linear to obovate, 3' long or less, 

 white-woolly beneath, at length dark green and 

 glabrous, or very nearly so above, the base com- 

 monly narrowly cuneate, at least the lower ones 

 pinnately lobed or toothed, their lobes lanceolate, 

 acuminate; upper leaves often linear and entire; 

 heads numerous, spicate-paniculate, i"-ii" broad; 

 involucre oblong, tomentose; receptacle naked; 

 central flowers fertile. 



In dry soil, Missouri to Texas, Wyoming, Colorado 

 and Arizona. Aug.-Nov. 



19. Artemisia mexicana Willd. Mexican Mug- 

 wort. Fig. 4589. 



Artemisia mexicana Willd.; Spreng. Syst. 3: 490. 1826. 



Perennial, less densely pubescent than A. ludoviciana, 

 2-3S high, often branched ; stem finely pubescent and 

 ultimately often floccose. Leaves ovate or orbicular in 

 outline on the lower part of the stem, 2'-3' long, 

 densely white-tomentulose beneath, green above, the 

 lobes of the lower and the blades of the upper entire 

 ones linear to narrowly linear or nearly so; heads small 

 and numerous, usually inclined or nodding ; involucre 

 campanulate, loosely woolly, the pubescence sparse. 



On prairies, hillsides and barrens. Missouri to Texas, 

 Arkansas and Mexico. Sept.-Oct. 



20. Artemisia gnaphalodes Nutt. Prairie 



or Western Sage. Cud-weed 



Mugwort. Fig. 4590. 



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

 Artemisia ludoviciana var. gnaphalodes T. & G. Fl. 

 N. A. 2: 420. 1843. 



Perennial; stem white-tomentose, usually 

 much branched, 1 "-4 high. Leaves lanceolate 

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

 the lower somewhat toothed, or rarely few- 

 lobed, white-tomentose on both sides, acute or 

 acuminate, sessile or the lower narrowed into 

 short petioles ; heads numerous, spicate-panicu- 

 late, about ij" broad; involucre oblong, to- 

 mentose; receptacle naked; central flowers 

 fertile. 



On prairies, plains, and dry banks, western On- 

 tario and Illinois to Alberta, Missouri, Texas and 

 Mexico. Locally established in waste grounds 

 from New Hampshire to Delaware. Far western 

 plants formerly referred to this species, which 

 consists of many races, are, apparently, distinct. 



34 



