Erigeron. COMPOSITiE. 219 



involucre commonly beset with some l)ristly liairs. — Syn. ii. 431 ; Hook. FI. ii. 20; Torr. & 

 Gray, Fl. ii. 175. E. keterophi/llus, Mnhl. in Willd. iii. 1956; Pers. 1. c. ; Pursh, Fl. ii. 148; 

 Bart. Veg. Mat. Med. t. 21. E. stri(josas, Rigel. Fl. Eost. ed. 2, 302, not Mulil. Aster annuiis, 

 L. Hort. Cliff. & Spec. ii. 875. Pulicaria annua, GiErtn. Fruct. ii. 462. Diplopappus duhius, 

 Cass. Bull. Philo"m. 1817 & 1818. Stenact'is dubia, Cass. Diet, xxxvii. 485. S. annua & S. 

 strigosa (excl. syn.), DC. Prodr. v. 299. Phalacroloma acutifulium, Cass. Diet, xxxix. 405. 

 — Fields and open grounds, common from Canada to Virginia: also in Oregon, &c., in a 

 form quite intermediate between tliis and the following. (Nat. in Eu.) 

 E. strigOSUS, Muhl. Pubescence appressed, eitlier sparse and strigose or close and minute : 

 stem seldom over 2 feet high : leaves of firmer texture, lanceolate and the upper entire ; 

 lower from spatulate-lanceolate to oblong, often sparingly serrate : involucre with few or no 

 bristly hairs. — Willd. Spec. 1. c. ; Ell. 8k. ii. 394 ; Hook. 1. c. ; Torr. & Gray, 1. c. E. ner- 

 vosum, Pursh, I. c, not Willd. E. amhujuus, Nutt. Geu. ii. 147. E. Philadelpldcus, Bart. 

 Veg. Mat. Med. t. 20. E. interjrifoUus, Bigel. 1. c. Doroniciim ramosum, Walt. Car. 205. 

 Phalacroloma ohtusifolium, Cass. Diet, xxxix. 405. Sfenartis ambigua, DC. 1. c. — Dry open 

 grounds, Canada and Saskatchewan to Texas, Oregon, and California. Passes into or mixes 

 with the preceding. Occurs rarely with abortive rays, var. discoideus, Robbins, in Gray, 

 Man. ed. 5, 237. 



Var. Beyrichii. A slender form, witli minute and sometimes almost cinereous pu- 

 bescence, smaller heads, and rays from white to pale rose-color. — Torr. & Gray, 1. c. E. 

 Begrichii, Hort. Berol. Stenactis Bej/richli, Eisch. & Meyer, Ind. Sem. Petrop. v. 27. Pha- 

 lacroloma Beyrichii, Eisch. & Meyer, 1. c. vi. 63. — Nebraska to Arkansas and Texas, perhaps 

 first coll. by Begrich. 



++ ++ Leaves pinnately parted into narrow divisions : rays very numerous (100 or more) and nar- 

 row: pappus alike in ray and disk; the bristles of the inner ver}' deciduous ; the short squa- 

 mellae of the outer more or less confluent into a nultidentate crown. — Original of Stenactis, 

 Cass, ex Benth. Palynctis, Less. Syn. Comp. 188, PolyactiUium, DC. Prodr. v. 281. 



B. Neo-Mexicanus, Gray. A foot or two high from a biennial or winter-annual root, 

 leafy, pauiculately branched, hispidulous or hispid with spreading bristly hairs : divisions of 

 the cauline leaves 3 to 9, linear or linear-spatulate, obtuse, of the radical shorter and broader : 

 rays white or purplish-tinged, narrowly linear, 4 or 5 lines long. — Proc. Am. Acad. xix. 2. 

 E. delphinifolius. Gray, PI. Wright, ii. 77 ; llothrock in Wheeler Rep. vi. 153 (where the root 

 is said to be perennial, which needs confirmation), not Willd. — Hillsides, New Mexico and 

 Arizona, Wright, Thurber, Palmer, Rothrocl-, Lemnion. 

 E. DKLPHiNiFOLius, Willd. (Stenactis, Cass., Polyactidiinn, DC), from which Bentham first 



distinguished our very similar species, appears to be wholly Mexican, has appressed pubescence 



and more numerous as well as more slender rays. 



§ 2. TrimorpiiJ;a. Rays inconspicuous or slender, numerous, sometimes not 

 exceeding tiie disk : within them a series of rayless filiform female flowers (com- 

 monly none in the last species) : leaves entire or nearly so. — Trimo)'p/tcea, Cass. 

 Diet, xxxvii. & liv. 



* Stems low from a truly perennial rootstock, mostly simple and monocephalous : ray-corollas 

 bearing a few long and articulated hairs on the upper part of tlie tube: short outer pappus 

 manifest. 



E. alpinus, L. A span or so high, 1-3-cephalous : herbage and involucre more or less hir- 

 sute : leaves entire ; lowest spatulate, uppermost usually linear : rays purple, about twice 

 the length of the pappus. — Spec. ii. 864; Engl. Bot. t. 464; Fl. Dan. t. 292; Hook. Fl. ii. 

 18, excl. vars. ; Reichenb. El. Germ. xvi. t. 914. — High region of Northern Rocky Moun- 

 tains, Drummond, only specimen seen is not certain. (Eu., N. Asia.) 



* * Stems a span to a foot or more high from a biennial or sometimes more enduring root, the 

 larger plants brandling and bearing several or numerous somewhat pauiculately disposed heads : 

 pappus nearly or quite simple. 



E. acris, L. More or less hirsute-pubescent, varying towards glabrous (not glandular): 

 cauline leaves mo.stly lanceolate, the lower and radical spatulate : involucre hirsute : rays 

 slender, equalling or moderately surpassing the disk and pappus, purple : filiform female 

 flowers numerous. — Spec. ii. 863; Engl. Bot. t. 1158; Reichenb. 1. c. t. 917; Blytt, Norg. 



