192 COMPOSITiE. Aster. 



loose and .similar. — A. arhcendens, var. Fremonti, Torr. & Gray, Fl. ii. 503. A. adscendens'? 

 partly, Gray, Bot. Calif, i. 324. A. laxifolius, in part, Hook. Loud. Jour. Bot. vi. 160. — 

 Rocky Mountains, from Montana to Colorado and Utah, in wet ground below the alpine 

 region, west to tlie Cascade Mountains, lat. 49°, and along the 8ierra iS'evada, California. 



Var. Parisllii. A dubious form (connecting with the next species /), with more im- 

 bricated and acute involucral bracts, their margins ciliolate. — Bear Valley in the San Ber- 

 nardino Mountains, S. E. California, Parish. 

 A. OCCidentalis, Nutt. A span to a foot or more high, smooth and glabrous (except 

 some minute pubescence below the head), slender; smaller plants simple, bearing solitary 

 or few heads ; larger with slender branches and several or more numerous corymbose or 

 paniculate heads (therse 4 or 5 lines high) : leaves mainly linear and narrow; cauline 1 to 

 3 inches long and only a line or two wide, rarely lanceolate and larger, occasioually (in 

 Nuttall's specimens) bearing one or two salient lateral teeth or lobes; radical sometimes 

 lanceolate-spatulate with long tapering base : involucre of narrowly or subulate-linear acutish 

 or acute thiunish loose bracts, obviously imbricated, of 2 or 3 lengths : rays light violet, 

 about 4 lines long. — Torr. & Gray, Fl. ii. 164 ( Tripolium occidentale, Nutt. Trans. Am. Phil. 

 Soc. vii, 296), a small and weak alpine form, apparently of a species which at lower eleva- 

 tions becomes taller, rather freely branched, and in Oregon passes into a diffusely much 

 branched and paniculate polycephalous form. — Moist grounds and along streams, Idaho to 

 Wasliiiigton Terr., and along the Sierra Nevada, California, to Kern Co. (^1. cestivus, Roth- 

 rock in Wheeler Rep.) ; first coll. in Oregon by DoiKjlas. 



Var. SCabriusculus. More strict, rather rigid, probably in drier soil with more ex- 

 posure to aridity, stem and leaves scabrous-puberulent, — ^4. itstivus, Eaton in Bot. King 

 Exp 141. — Mountains of N. E. Nevada and Utah, Watsori, Wood. 



Var. intermedius. Ambiguous between A. occidental is and a glabrous variety of 

 A Menziesii or of A adscendens, a foot or two high, rather rigid, somewhat sparingly leafy, 

 with paniculate flowering branches • short outer bracts of the involucre often quite obtuse, 

 but narrower than in the two last-mentioned species •. radical and sometimes cauline leaves 

 lanceolate. — Wet meadows. Falcon Valley, &c., Washington Terr., SuksdorJ', Jloicell, Brun- 

 degee, and N. California, Priiujie. 



2. Tall (3 to 8 feet high) and branching, leafy to the top, paniculate ly polycephalous: Southwestern. 

 A. hesperius. Resembles A. paniculutas and A. salict/olins of the East, equally variable, 

 from nearly glabrous and smooth to scabrous-pubescent . leaves lanceolate, entire or the 

 larger with a few denticulations (2 to 5 inches long, 3 to 8 lines wide) : heads rather 

 crowded, 4 or 5 lines high : involucre of narrowly linear or more attenuate acute or gradu- 

 ally acuminate erect bracts, either unequal and imbricated, or with some loose and slender 

 herbaceous exterior oues which equal the inner ; rays either white or violet, 3 or 4 lines 

 long. — Damp soil and along streams, S- Colorado and New Mexico to Arizona and S. Cali- 

 fornia. Has been variously taken for A. lonc/ijolius, Novi-Belgii, astivus, &c., and coll. by 

 Wriijld, G'X'cne, Rothrock, Cleveland, Parish, Lemmon, &c. 



c. Involucre loose and foliaceous-bracteate at least some of the outer bracts herbaceous or foliaceous 

 to the base or nearly si, equalbng the inner, and more or less enlarged, either asceiidinu; or 

 squarrost'-spreading: the involucre of ijriniary or early heads is more foliaceous; but, when the 

 heads are more numerous, the enlarged outer bracts are not rarely wanting. 



1. Heads small. 

 A. Oreganus, Nutt. Nearly glabrous: stem, rather slender, 2 feet high, paniculately 

 branched at summit, or bearing several to many paniculate heads ; these about 3 lines high : 

 leaves linear-lanceolate, entire (2 to 4 lines wide) .- outer and herbaceous involucral bracts 

 lanceolate, acute, not longer than the thin and narrow iimer oues (in some heads few or 

 none) ; rays about 2 lines long, white or purplish. — Torr & Gray, Fl. ii. 163, viz. Tripolium 

 Oreganum, Nutt. Trans. Am. Phil Soc. vii. 296, on small and hardly developed specimens. 

 A simplex and perhaps A cornens, Eaton in Bot. King Exp. 1. c. A larifolius, in part. Hook. 

 Loud Jour. Bot. vi. 240, not Nees. — Wet banks of streams and boggy meadows, Idaho and 

 N. Nevada to Oregon and Washington Terr. : probaldy also N. California. 



2. Heads middle-sized or large: rays violet or purple. (Species confluent.) 

 A. Douglasii, Lindl. Smooth, glabrous or nearly so : steins 2 or 3 feet high, with erect 

 or ascending branches, bearing several or numerous paniculate heads ; these 5 or 6 lines 



