Rydberg: Rocky Mountain flora 129 



leaves, lanceolate in outline, and taller stem. In the true A. nor- 

 vegica the basal leaf-blades are as broad as long and have usually 

 only 5 principal divisions. 



Artemisia Brittonii sp. nov. 



Perennial with a horizontal rootstock ; stem rather stout, 3-6 

 dm. high, white-floccose ; lower leaves cuneate or oblong-oblance- 

 olate, 3-5-lobed mostly above the middle, densely white-tomentose 

 on both sides, the lobes lanceolate ; upper leaves ovate-lanceolate, 

 entire ; inflorescence paniculate ; panicles narrow and heads con- 

 glomerate, 3-4 mm. high, about 2 mm. broad ; bracts ovate and 

 densely floccose ; flowers about 15, heterogamous, light-brown or 

 yellow ; achenes and receptacle glabrous. 



This is related to A. ludoviciana Nutt, but differing in the 

 stouter habit, more crowded inflorescence, and principally in the 

 leaves, which are equally tomentose on both sides. 



Colorado: Golden, 1882, N. L. Britton (type, in herb. 

 Columbia College); Boulder, 1891, Penard 285; also 1902, 

 Tzvecdy jpod. 



Utah : Green River, 1850, Stansbury ; Salt Lake Valley, 

 Lauderdale ; Salt Lake City, 1884, Harry Edwards. 



Artemisia Underwoodii sp. nov. 



Perennial, with a horizontal much-branched rootstock ; stems 

 slender, 2-6 dm. high, somewhat floccose, usually simple up to 

 the inflorescence ; leaves 3-5 cm. long, pinnately parted, with 

 3-7 (usually 5) linear or linear-lanceolate acute lobes, densely 

 white-floccose beneath, green and slightly tomentose above at 

 first, but in age glabrate ; inflorescence paniculate, but panicle 

 narrow and the small heads crowded ; heads campanulate, 

 scarcely over 3 mm. high and 2.5 mm. broad; bracts ovate, 

 tomentose, slightly scarious on the margin ; flowers 1 5-20, 

 heterogamous, brown ; achenes and receptacle glabrous. 



This is nearest related to A. ludoviciana, but differs in the 

 deeply parted leaves and their narrow lobes. It grows on 

 chaparral-covered hills and mountain-sides at an altitude of 

 2300-2700 m. 



Colorado: Ouray, 1901, Underwood & Sclby 7./ (type) and 

 34.; Georgetown, 1895, Rydberg. 



