ASTER COMPOSITE 811 



BUCEPHALUS 



feet high, ratber stout: cauline leaves mostly narrowed' below 

 with more or lees aariculate half-clasping base : the lower 5 inches long fcy 

 an inch broad, not petiolar-contracted : heads terminating, simple leafy 

 branches : rays 8-9 lines long. Between Kootenay and Pend Orielle, Wash- 

 ington. 



A. Henderson! Fernald. Stems rather slender, loosely tomentose 

 above, branching near the top, leafy : upper leaves lanceolate, more or 

 leas acuminate, entire, one-nerved, glabrous except the midrib, auriculate, 

 clasping by a broad base, 2-4 inches long : heads numerous, in an ample 

 panicle: bracts of the involucre linear, acute, green or the inner wi h whi- 

 tish base, all of nearly equal length, equalling or surpassing the disk, 4-5 

 lines long: rays numerous, 8-10 lines long by a line broad, bright purple. 

 Eastern Washington to Idaho. 



18 BUCEPHALUS Nutt. trans. Am. Phil, Soc. vii, 298. 



Perennial leafy-stemmed herbs without radical leaves and 

 solitary or panicled heads of purple, blue or white ray-flowers 

 in a single series, not very numerous, pistillate: disk flowers 

 tubular and perfect. Bracts of the turbinate campanulate in- 

 volucre regularly imbricated in 3-4 series, dry and chartaceous, 

 ovate, concave, somewhat carinate, the innermost about the 

 length of the disk, the outer successively shorter but similar. Al- 

 veola of the receptacle lacerate. Appendages of the style lanceo- 

 late, acute. Achenes oblong, compressed. Pappus copious, 

 rather longer than the corolla : the bristles unequal; the longest 

 ones sometimes thickened upwards. Stems very leafy, the lower 

 leaves being reduced to bract-like scales, or bristles. 



E. elegans Nutt. Trans. Am. Phil. Soc. vii, 298. Aster eUgans 

 T. & G. Stems slender, 1-3 feet high, mostly scabro puberu- 

 lent, leaves thickisia, lancesl?.te, 1-2 inches long, erect, closely sessile, the 

 upper apiculate-mucronate : heads several at the summit of simple stems 

 or branches, 4-5 limshigh: bracts of the involuc e a'l close and conspicu- 

 ously woolly-ciliate, barely acute, outer ovate, none with pointed tips : 

 rays rather few, about 4 lines long: style appendages linear- subulate, 

 hardly acute, equaling the stigma ic portion : achenes flat, hirsute, becom- 

 ing glabrate at maturity. On mountains of Eastern Oregon and Wash- 

 ington to Montana, Wyoming and Nevada. 



E. Engelmannii Greene Pitt, iii, 54. Aster Engelmanii Gray 

 Commonly, rather tall and robust, green, slightly puberulent 

 to glabrous : leaves thin, ovate-oblong to broadly lanceolate, 

 2-4 inches long, loosely veined, the larger sometimes with a few 

 small acute teeth, the upper commonly tapering at apex into a slender or 

 cuspidate acnmination: heads fully half inch high, hemispherical, either 

 racemosely disposed on slender axillary peduncles or somewhat thyrsoid- 

 cymose : bracts of the involucre mostly acute or acuminate : some outer 

 ones loose, narrow and partly herbaceous, or with loose pointed tips; in- 

 ner ones purp ish rays about 6 lines long : style, appendages attenuate-sub- 

 ulate : achenes obovate-oblong with narrowish summit. In the higher 

 mountains of Oregon and Washington to the Rocky mountains. 



E. serrulatus Greene 1. c. 55. "Stoutish and rather tall, vivid green 

 and scabrous, the leaf margins even serrulate-scabrous under a lens : 

 leaves linear-lanceolate, 2 inches long, acute, marked by a very strong and 

 conspicuous white mid-vein and some reticulation of the surface : heads 

 few, large as in the preceeding, but bracts very 'different, being narrow 



