COMPOSITAE (composite , family) 583 



dense, corymbiform; heads 8-9 mm. high; bracts about 20, linear, acute, the 

 calyculate ones few, minute: rays dark orange, i-7 mm. long, 3-4-nerved: 

 achenes angled, glabrous. (S. pyrrhochrous Greene, PI. Baker. 3: 24. 1901; 

 S. Traq/i Rydb. 1. q. 33: 159.)— Wyoming and Colorado. 



, Si. Senecio Balsamitae'Muhi: Willd. Sp. PI. 1999. 1804. Light or yellowish- 

 green slender perennial, in age glabrate or slightly floccose at the base of the 

 leayes; stem 3-4 dm. high, striate, pale: basal leaves 3-8 cm. long, obovate or 

 broadly oval, generally tapering into the petioles, but sotnetimes truncate at 

 the base, obtuse, crenate or sinuate, light green; lower stem leaves oblanceolate 

 in outline and petioled; the upper lapceolate or linear in outline and sessiltl; all 

 deeply pinnatifid with narrow oblong or linear segments: cymes corymbiform; 

 heads 7-8 mm. high; bracts Unear, acute; C'Alyculate ones few, linear, small 

 and crisped: rays yellow, about 6 mm. long: achenes hispid-puberulent on the 

 angles. S. aureus Ba^samUae. {S. flaOulus Greene, Pitt. 4: 108. 1900; S. 

 flqvovirens a.nd S. aurellus Rydb. 1. c. 181 & 182.) — Across the continent; ours 

 thought' by SQihe to be distinct ; if so, the hame S. 'flavuhts will stand. 



I 35. Senecio mutabilis Greene, 1. c. 113. Stems in a small dense tuft, erect 

 or ascending, 1-3 dm. high; pubescence varied, from tomentulose or loosely 

 floccose-hoary to almost or quite wanting: leaves obovate-spatulate to broadly 

 linear or lanceolate, nearly entire or serrate to sinuately or pectinately or 

 even somewhat lyrately pinnatifid, the apex often tridentate: heads few to 

 many, 8-10'mm. high, the involucres glabrous: rays mostly tridentate and 

 4-nerved, light yellow to nearly orange-color. S. aureus compactus. (S. com- 

 ppciMs.Rydb.,JME®™r Torr. Bot. Club 5: 342, 1893, not S. compactus Kirk; S. 

 aUanceomius s^nii S. tridentieulatus Rydb. Bull. TJorr. Bot. Club 27: 175 & 176. 

 1900; S. eondensatus Rydb. Fl. Col., not S. condensatus Greene, which is a 

 plant of tile: Blue Moxmtains, Washington.) — Wyoming to New Mexico and 

 Utah.' , ' 



36. Senecio discoideus (Hook.) Brit. 111. Fl. 3: 479, 1898. . Perennial, 

 glabrous except for small tufts of wool in the axils of the lower leaves; stem 

 rather stout, 3-6 dm. tall: basal leaves oval to ovate, obtuse, thin, sh3.rply 

 dentate, abruptly narrowed into petioles longer than the blade; stem leaves 

 few, small, more or less laciniate: heads few or several, slender-peduncled, 

 corymbose; bracts of, the involucre narrowly linear, 6-10 mm. longj' rays 

 usually very short, or none. S. aureus discoideus. (S. fedifoliv^ Rydb. 1. c. 

 183; S. nephrophyllus Rydb. Mem. N. Y. Bot. Gard. 1: 446. 1900.)— Wet 

 places in the valleys in our range; across the continent northward. , 



37. Senecio eremophilus, Rich. App. Frankl. Joum. 2: 31. 1823. Siems 

 freely brancMrig, leafy up to the inflorescence: leaves mostly oblong in outline, 

 laciniately pinnatifid of pinnately parted, the lobes usually incised or acutely 

 dentate: heads^; numerous in corymbiform cymes, 8-10 mm. high,,, short- 

 peduncled; involucre campamilate or narrower, minutely bracteolate? proper 

 bracts coinmonJY I?urple-tipped: ii:ays 7-9, 4-6 mm. long: achenes either 

 minutely papillose-cinereous or glabrous. (S. MacDougattii Heller, 1. c. 592.) — 

 Extending southward through the Rocky Mountains (from British America) 

 to New Me:5i5lQO and Arizona. 



38. Senecio filifolius Nutt. Trans. Am. Phil. Soc. 7: 414., .1841. More or 

 less permanently tomentose; stems suffruticose at base, much-branched, the 

 branches diffuse, very leafy to the summit: leaves pinnately 5-9-parted; the 

 segments very narrowly Unear, entire, obtusish, often unequal, mostly with 

 revolute margins: heads (rather.large) corymbose, on short peduncles, calycu- 

 late wijtJi.afeTy^ small subulate scales: rays about 7, Unear, somewhat elongated: 

 achenes strigose-canescent. — In valleys; from Colorado a^id Utah tq^^izona 



39. Senecio Riddellii T. & G. Fl. 2: 4^4;. 1842. Glabrous throughout; stem 

 terete; I very leafy, corymbose at the summit: cauline leaves pinnately .5-9- 

 parted-; the segments narrowly Unear, obtuse; entire, flat, somewhat dilated 

 towards the apex (thickish and rather rigid): heads (large and showy) on 

 short: peduncles,, disposeid in a compound corymb, calyculate with subulate 

 bracts:; rays i^bout 12, linear, elongated: achenes minutely puberulent. (iS. 



