182 BOTAl^Y. 



pale greenish shrub, with ragged fibrous bark and a strong aromatic smell, 

 the " sage-brush ". of the^West, covering hundreds of square miles in the 

 plains and on the foot-hills of Nevada and Utah, found more sparingly in the 

 mountains to their" summits, and extending from Oregon to Arizona, and as 

 far east as the mountains of Colorado ; 4-10,000 feet altitude ; Septem- 

 ber. (635.) 



Artemisia aebuscula, Nutt. Dvs^arf, shrubby, canescent; stems 3-6' 

 high ; leaves narrowly cuneate, 4-5" long, deeply 3-cleft, the side divisions 

 often 2-3-lobed ; heads ovoid, sessile singly or in small clusters along a sim- 

 ple or sparingly-branched rachis ; involucre of oval tomentose imbricated 

 scales, the outer ones shortest, inner more scarious ; florets about 8, all per- 

 fect and fertile, the corollas a little more slender than in the last, and the 

 styles similar. — Arid plains of Snake River, (Nuttall ;) Colorado, (Vasey, 

 308.) On a peak in the East Humboldt Mountains ; 9,000 feet elevation ; 

 August. (636.) 



Artemisia trifida, Nutt. Shrubby, 6-18' high, canescent ; leaves 

 narrowly cuneate, 3- or rarely 4-5-cleft, the lobes linear or oblong, obtuse ; 

 heads narrowly obovoid, arranged in small peduncled clusters forming a nar- 

 row elongated panicle ; involucral scales imbricated ; the outer scales oval, 

 tomentose ; inner ones obovate, scarious ; florets about 3, all perfect and fer- 

 tile ; corollas and styles as in the last. — A taller and more slender plant than 

 A. arbuscula, with more compound inflorescence, narrower heads, and fewer 

 florets — 3 in all the heads examined, though said to be 8 by Torrey and 

 Gray; possibly a misprint; for Nuttall says of ^. arhuscula, " Capituli twice 

 as large "as in A. trifida. Washington Territory; Oregon and California. 

 Scattered throughout Northern Nevada, often in company with A. tridentata, 

 which it greatly resembles in habit, though smaller, and sometimes itself 

 covering large areas ; 5-8,000 feet elevation ; August, September. (637.) 



Artemisia potentilloides, Gray. Proc. Amer. Acad., 6. 551. Silky- 

 canescent, many-stemmed from a perennial woody caudex ; stems herbaceous ; 

 9-12' high ; radical and lower leaves 2-3' long, 2-3-pinnately cleft, the nu- 

 merous linear divisions 2-4" long and J" wide ; upper leaves gradually 

 smaller, simply pinnatifid with linear obovate divisions ; uppermost simple and 

 bract-like ; heads 3-6, corymbose, hemispherical, 3-4" broad ; involucre cup- 

 shaped, of about 10 equal obovate scales with hyaline edges ; receptacle con- 

 vex, very hirsute; florets exceedingly numerous, all alike, perfect and fertile; 



