218 COMPOSITE. Erigeron. 



radical not larger, obovate or spatulate, slender-petioled : heads solitary, terminating the 

 branches, on rather slender peduncles : involucre broad, 3 lines high, slightly pubescent : 

 rays about 50, apparently white, 4 lines long, not very narrow : pappus indistinctly double, 

 the outer short and setulose. Mogollon Mountains, New Mexico, Rusby. 

 E. Ariz6ni.CUS, GRAY. Cinereous-hirsute throughout: stem 2 feet high from an annual 

 root, strict, with simple branches, leafy : leaves oblong-lanceolate and sessile, or lower ob- 

 ovate-oblong and petioled, an inch or two long : heads solitary and short-peduneled, termi- 

 nating the branches, half-inch high and broad: involucre hirsute: rays 80 to 100, white, 

 4 or 5 lines long : outer pappus very conspicuous, setose-squamellate. Near Tanner's Canon 

 in the Iluachuca Mountains, S. Arizona, Lemmon. 



= = Rays of the small heads rather numerous but small, shorter than or barely equalling the 



flowers of the convex disk. Verges to Ctenotus. 



E. incomptus. A foot or two high, branched from the base, slender and erect, hirsute 

 with short spreading pubescence, leafy : leaves narrowly linear (half-inch or inch long, a line 

 or less wide), or lower narrowly spatulate-lanceolate and attenuate into slender petiole : heads 

 slender-peduncled : involucre 2 lines high, shorter than the hemispherical disk : rays either 

 very numerous or fewer, slender, with ligule only a line long, bluish or purplish : outer pappus 

 conspicuous, subulate-squamellate, longer than the breadth of the glabrate akene ; inner 

 scanty and rather deciduous. Carysito, Lower California, near the U. S. border, within 

 which it probably occurs, C. R. Orcutt. 



= = == Rays of the small heads only 30 or 40, well exserted, white, not very narrow, barely 

 3 lines long, and with pappus as in the disk -flowers : leaves narrow, entire. 



E. modsstus, GRAY. A foot or less high and much branched from an indurated but an- 

 nual root, slender, rigid, cinereous-hirsute or hispid: branches terminated by the small (2 

 lines high) slender-pedunculate heads: upper leaves linear and lower narrowly spatulate, 

 about an inch long. PI. Fendl. 68 (excl. syn.) & PL Liudh. ii. 220. Dry and sterile rocky 

 plains, W. and N. W. Texas, Lindhcimer, Wright, &c. 



= = == = Rays of small or barely middle-sized heads very numerous (about 100), narrow, 

 with pappus like the disk-flowers; the inner of rather scanty bristles; outer of short subulate 

 squainelhc: leaves from entire to sparingly lobcd. 



E. divergens, TORR. & GRAY. Diffusely branched and spreading, a foot or less high, 

 cinereous-pubescent or hirsute : leaves linear-spatulate or the upper linear and the lowest 

 broader (these 2 to 4 lines wide, sometimes laciniately toothed or lobed) : heads 2 or 3 lines 

 high, and the white or purplish or sometimes violet rays equally long : involucre hirsute : 

 receptacle in age commonly very convex. Fl. ii. 175; Gray, PI. Feud!., PL Wright., 

 &c. E. strigosus, var.. Hook. Fl. ii. 18, in part. E. (Oligotrichium) divaricatus^ntt. Trans. 

 Am. Phil. Soc. 1. c. 311. Low plains and river-banks, Nebraska to W. Texas, Washington 

 Terr., and California. (Adj. Mex.) 



Va.r. cmereus, GRAY, 1. c. Dwarf and flowering almost from the root, with the 

 earliest heads on slender almost scapiform peduncles ; or leafy and later heads shorter- 

 peduncled : pubescence soft and cinereous. E. cmereus, Gray, PL Fendl. 68. E. nudijiorus, 

 Buckley in Proc. Acad. Pliilad. 1861, 456. W. Arkansas to Arizona. (Adj. Mex.) 



E. tenuis, TORR. & GRAY. Branched from the annual or biennial root, ascending or erect, 

 a span or two high, somewhat hirsute or pubescent : leaves oblong-spatulate or lanceolate, 

 and the lowest obovate (4 to 6 lines wide), occasionally few-toothed or sinuate-lobed : heads 

 little over 2 lines high: involucre nearly glabrous : rays white and purplish. Fl. ii. 175. 

 E. quercifolium, Nutt. ; DC. Prodr. v. 285, not Lam. E. Brazoensis, Buckley, 1. c. Low 

 grounds, Arkansas, Louisiana, and Texas. 



= = = = = Rays of the small heads not excessively numerous, nor very narrow (2 or 3 

 linos long), white or barely purplish-tinged; the bristles of their pappus commonly wanting or 

 very few: outer pappus a short crown of distinct or partly united slender squamellse, persistent 

 after the fragile inner pappus has fallen : tall and erect winter annuals or biennials, leafv, 

 branched above, bearing coryrnbosely cymose or paniculate heads, commonly produced all sum- 

 mer: leaves green, sometimes serrate or the lower incised: weedy species, of wide distribution; 

 the two generally distinct in the Atlantic States, hardly so on the Pacific side. Phalacroloma, 

 Cass. Diet, xxxix. 404. 



E. dnnuus, PERS. Sparsely hirsute with spreading hairs, 2 to 5 feet high : leaves membra- 

 naceous, from ovate to broadly lanceolate, mostly serrate, lower often very coarsely so : 



