Aster. COMPOSITE. 199 



Var. lutescens. Rays pale yellow, small. — A. lutescens, Torr. & Gray, Fl. I.e. 

 Diplojnijjpus albuv, var. lutescens, Hook. 1. c. D. lutescens, Liiidl. in DC. 1. c — Saskatchewan, 

 on dry limestone rocks of Red River, Douglas, a broadish-leaved scabrous-puberulent form. 

 Englewood, N. Illinois, E. J. Hill, a slender and smooth form, with numerous and unusually 

 small heads. 

 A. Lemmoili. Slender, from filiform rootstocks, somewhat strict, smooth and glabrous, 

 bearing a few rather scattered heads : leaves not rigid nor lucid, not nervose ; cauliue some- 

 what gramineous, narrowly linear and attenuate (larger 4 or 5 inches long, a line or two 

 Avide), on flowering branches gradually reduced to subulate-attenuate; radical shorter, lan- 

 ceolate-oblong or spatulate : involucre (3 lines high) equalling the disk, of about 3 series 

 of thin linear and acute or acuminate bracts : rays 2 lines long : pappus of soft and slender 

 bristles: akenes minutely cauesceut. — Along mountain streams in S Arizona: Santa Rita 

 Mountains, Pringle, and Huachuca Mountains, Lemmon. 



* * Involucre rather loosely imbricated, of thin narrowly linear-lanceolate attenuate-acute bracts 

 in not more than 3 series : akenes glandular, several-nerved : stems leafy, a foot or two high 

 from lilit'orm creeping rootstocks, bearing several or sometimes solitary long-peduncled middle- 

 sized heads : leaves mostly pinnately veined, thin or thinmsh, from lanceolate to oblong-ovate. 

 Northern Atlantic species. 



A. acuminatus, Micjix. Somewhat pubescent or puberulent : stem leafless below, leafy 

 and somewhat corymbosely branched above, or often simple, sometimes flexuous : leaves 

 membranaceous, 3 to 6 inches long, mostly oblong with cuneiform-attenuate base and slender 

 acuminate apex, sharply and coarsely dentate, primary veins abundant and conspicuous: 

 heads usually several and corymbiform-paniculate, barely half-inch high : rajs linear, white, 

 or tinged purplish : style-appendages lanceolate-subulate, slender : akenes narrow. — Fl. ii. 

 109 ; Hook. Bot. Mag. t. 2707, & 11. ii. 9 ; Torr. & Gray, Fl. ii. 157, not Xees. A. divaricatus, 

 Lam. Diet. i. 305 (herb. Juss.), not L. A. diffusus, var. acuminatus, Pers. Syn. ii. 447. 

 Diplostephium acuminatum, DC. Pi'odr. v. 273. — Deej) and cool woods, S. Labrador to Penn- 

 sylvania, and along the mountains to Georgia. 



A. nemoralis, Ait. Somewhat puberulent : stem slender, very leafy above, sometimes 

 simple and bearing a single slender-pedunculate head, often corymbosely or somewhat umbel- 

 lately branched abo^e, the branches similarly monocejjhalous : leaves from oblong-lanceolate 

 to broadly linear, an inch or two long, acutish or obtuse, tipped with a callous point, entire 

 or slightly few-toothed, scabrous above ; those of the flowering branches or peduncles linear- 

 subulate and scattered : involucre of more numerous linear-sulnilate puberulent bracts : rays 

 broadly linear, lilac-purple : style-appendages broadly lanceolate : akenes broader. — Ivew. 

 iii. 198; Nutt. Gen. ii. 154; Torr. & Gray, 1. c. A. uniflorus, Michx. Fl. ii. 110, small and 

 simple-stemmed form. A. ledifolius, Pursh, Fl. ii. 544. Galatella nemoralis, Nees, Ast. 173. 

 — Bogs and swamps, Newfoundland and Hudson's Bay to New Jersey. 



* * * Involucre closely and regularly appressed-imbricated in several series of ovate or ovate- 

 lanceolate dry and chartaceous (sometimes purplish-tinged) bracts : akenes oblong, compressed, 

 more or less pubescent: stems leafy to the top, bearing several or rarely solitary pedunculate 

 heads: leaves mostly pinnately veined, sessile, from lanceolate to oblong-ovate, commonly 

 entire. Rockj' IMoiintain and Northwestern species. — Eucepludus, Nutt. 



•t— Style-appendages subulate, equalling or longer than the stigmatic portion: involucral bracts 



all thin and dry, acute or acutish, commonly tomentose-ciiiate, at least when young : akenes 



rather broad and flat, hirsute, becoming glabrate at maturity: stems mostly- simple and 2 or 3 



feet high, striate-angled: heads show}': rays purple or violet. 



A. Engelmanni, Gray. Commonly rather tall and robust, green, slightly puberulent to 



glabrous : leaves thin, ovate-oblong to broadly lanceolate (2 to 4 inches long), loosely veined, 



the larger sometimes with a few small acute teeth, upper commonly tapering at apex into a 



slender or cuspidate acumiuation : heads (fully half-inch high), hemispherical, either race- 



mosely disposed on slender axillary peduncles or somewhat thyrsoid-cymose : involucral 



bracts mostly acute or acuminate ; some outer ones loose, narrow and partly herbaceous, or 



with loose jjointed tips ; inner purplish : rays about half-inch long : style-ajjpeudages atten- 



uate-sul)ulate : akenes obovate-oblong with narrowish summit. — Am. Jour. Sci. ser. 2, 



xxxiii. 238, without char. A. eler/ans, var. Enr/elmanni, Eaton, Bot. King Exp. 144. — Rocky 



IVIountains, Utah and Wyoming to the Brit, boundary and in the Cascades, Washingtcu 



Terr. ; first coll. by H. Engelmann and Lijall, 



