570 COMPOSITAE (COMPOSITE FAMILY) 



laciniate divisions and lobes, white beneath with close cottony tomentum, 

 glabrate above: heads glomerate in an interrupted spiciform or virgate 

 panicle, 3-4 mm. high; involucre hemispherical-campanulate, greenish and 

 scarious, glabrous or soon becoming so, 20-30-flowered. [A. elatior (T. & G.) 

 Rydb. as to our range.] In the mountains; Colorado to Montana and Wash- 

 ington. 



20a. Artemisia discolor incompta (Nutt.) Gray, Syn. Fl. 1: 373. 1886. 

 Stouter, with coarser or less dissected leaves, having mostly broader lobes, or 

 the upper entire. Mountains; Wyoming and Montana to California and 

 Washington. 



21. Artemisia Bigelovii Gray, Pacif. R. R. Rept. 4: 110. 1856. Silvery- 

 canescent throughout, 2-4 dm. high: leaves oblong- to linear-cuneate, mostly 

 3-toothed at the truncate apex, 10-14 mm. long: heads very numerous and 

 crowded in the oblong or virgate thyrsiform panicle, tomentose-canescent, 

 containing only 1 or 2 hermaphrodite and as many pistillate flowers, all fer- 

 tile. Rocky banks; Colorado, on the Upper Canadian and Arkansas. 



22. Artemisia trifida Nutt. Trans. Am. Phil. Soc. 7: 398. 1841. Silky- 

 canescent; stems 2-6 dm. high, much-branched: leaves 3-cleft toward the 

 apex or 3-parted, the lobes and entire upper leaves narrowly linear or slightly 

 spatulate-dilated : heads numerous in the contracted leafy panicle, or spi- 

 cately disposed on its branches; involucre 3-9-flowered, the outer or accessory 

 bracts oblong to short-linear or lanceolate. (A. tripartita Rydb. Mem. N. Y. 

 Bot. Gard. 1: 432. 1900.) Elevated plains in our range and Vest to the coast 

 States. 



23. Artemisia arbuscula Nutt. 1. c. Dwarf, 1-3 dm. high, with a stout 

 base and slender flowering branches: leaves short, cuneate or flabelliform, 

 3-lobed or parted, with the lobes obovate to spatulate-linear, sometimes again 

 2-lobed; those subtending the heads usually entire and narrow: panicle strict 

 and comparatively simple and naked, often spiciform and reduced to few 

 rather scattered sessile heads: involucre 5-9-flowered. (A. spiciformis Osterh. 

 Bull. Torr. Bot. Club 27: 507. 1900.) High mountains and elevated plains; 

 Colorado and Wyoming to the northwest. 



24. Artemisia tridentata Nutt. 1. c. A shrub or small tree 0.5-5 m. high, 

 much-branched: leaves cuneate, 15-30 mm. long, 3-7-toothed or lobed at 

 the truncate summit, uppermost cuneate-linear: heads very numerous, in 

 large dense panicles; involucre 5-8-flowered, oblong, the outer or acces- 

 sory bracts short, ovate-obtuse, tomentose-canescent. The common SAGE- 

 BRUSH; also called BLACK SAGE. Dry plains and mountains; west of the 

 Missouri. 



25. Artemisia nova A. Nels. 1. e. 27: 274. The shrubby base low, scraggy- 

 branched, the herbaceous stems numerous, fascicled, slender, simple, 1-2 dm. 

 high including the narrow spike-like panicle, grayish with a thin tomentum 

 or merely pubescent, as also are the leaves: leaves very narrowly cuneate, 

 1-2 cm. long, 3-toothed at apex, the middle tooth usually longest: panicle 

 leafy at base, naked above, strict and nearly simple; heads small, very nu- 

 merous, only 3-4 mm. long, usually 3-flowered but often only 1 or 2; invo- 

 lucral bracts closely imbricated, greenish, only slightly puberulent. Hillsides 

 and ridges in the foothills and on the plains; Colorado and Wyoming. 



26. Artemisia cana Pursh, Fl. 2: 521. 1814. Shrubby, densely white- 

 canescent; stem much-branched, 3-7 dm. high: leaves linear, linear-oblong, or 

 narrowly lanceolate, sessile, acute at both ends, 3-5 cm. long, 3-6 mm. wide, 

 usually quite entire, rarely with 2 or 3 acute teeth or lobes: heads numerous, 

 about 3 mm. broad, glomerate or sometimes solitary in the axils of the leaves, 

 or crowded into a naked thyrsus at the summit, 5-9-flowered; involucre ob- 

 long, canescent, the inner bracts oblong or lanceolate, obtuse, usually with 

 1-3 shorter outer ones. Plains and mountain valleys; throughout our range 

 and to the northwest. 



26. Artemisia cana viscidula Osterh. 1. c. The herbage tending to become 

 glabrute ;md obscurely viscidulous. (A. viscidula Rydb. Bull. Torr. Bot. 

 Club 33: 157. 1906.) Colorado and Wyoming. 



