578 COMPOSITAE (COMPOSITE FAMILY) 



few-several, rarely solitary. (S. scopulina Greene, 1. c. 117.) In the moun- 

 tains of Colorado and southern Wyoming. 



2. Senecio cernuus Gray, Am. Journ. Sci. 33: 239. 1862. Quite glabrous, 

 4-8 dm. high: leaves lanceolate or the larger oblong-lanceolate, entire, den- 

 ticulate, rarely with a few scattered coarser teeth, all tapering at base into a 

 barely margined petiole, or the upper into a narrowed not clasping base : heads 

 several or numerous in the panicle, most of them decidedly nodding: flowers 

 pale yellow. (S. pudicus Greene, 1. c. 118; S. accedens Greene, Erythea 

 3: 105. 1895, probably.) In the mountains of Colorado and New Mexico. 



3. Senecio amplectens Gray, 1. c. 240. Lightly floccose-woolly at first, soon 

 glabrate, 2-3 dm. high, few-several-leaved, terminated by 1 or 2 long- 

 pedunculate nodding heads: leaves denticulate to conspicuously and sharply 

 dentate; the radical obovate to spatulate, tapering into a winged petiole; the 

 cauline as large or larger, oblong or narrower, half-clasping or more, the upper 

 by a broad base : involucre dark-pubescent, 15-20 mm. high, of linear bracts and 

 a few loose calyculate ones: rays linear, 2 cm. or more long, acute or acutely 

 2-3-toothed at tip. Alpine and subalpine region; mountains of Colorado. 



4. Senecio Holmii Greene, Pitt. 4: 120. 1900. Commonly 1-2 dm. high, 

 the stoutish stems mostly several from a branching rootstock, leafy at base 

 only, the pedunculiform stem with only 1 or 2 reduced leaves; herbage ap- 

 pearing glabrous, minutely hirtellous at base of involucre, on the peduncles, 

 and occasionally the leaf-margins: leaves ovate to obovate and oblong- 

 lanceolate, callous-dentate or denticulate, 5-10 cm. long, on petioles nearly as 

 long: heads 1-5, large and nodding: rays 20 mm. long or more, 5-7-nerved. 

 (S. pagosanus Heller, Muhl. 1: 7. 1900; S. lactucinus Greene, 1. c. 121. 1900, 

 not S. lactucinus Greene, Erythea 3: 223. 1893. 1. c.) In the alpine regions 

 of Colorado. 



5. Senecio taraxacoides (Gray) Greene, 1. c. 119. Dwarf, the leafy and 

 usually monocephalous stem only 5-8 cm. high, erect from an erect rather 

 stout and fleshy rootstock; herbage, the involucre excepted, permanently 

 arachnoid-tomentulose: leaves 3-5 cm. long, more or less runcinate-pinnatifid, 

 the whole leaf -margin commonly revolute: head only horizontally nodding; 

 involucre dark green, glabrous except for a few white arachnoid hairs: rays 

 10-14 mm. long, light yellow, 4-nerved. Alpine in the Colorado mountains. 



6. Senecio Soldanella Gray, Proc. Acad. Phila. 67. 1863. Apparently 

 glabrous from the first, 8-14 cm. high, somewhat succulent: leaves mostly 

 radical and long-petioled, round-reniform to spatulate-obovate, denticulate 

 or entire; the cauline 1, or 2, or none: head solitary, erect, 18-25 mm. high; 

 involucral bracts lanceolate and a very few calyculate ones: rays 6-10, oblong, 

 7-10 mm. long. High alpine, in the mountains of Colorado. 



7. Senecio carthamoides Greene, 1. c. 122. Stems tufted, decumbent, and 

 becoming leafless below, the whole plant 1-3 dm. high: leaves variously obo- 

 vate and obovate-oblong, commonly 4-5 cm. long or more, sessile by a broad 

 somewhat hastate and clasping base, the margin coarsely and doubly dentate, 

 the teeth callous-tipped: heads 10-14 mm. high, erect, subcampanulate, either 

 very short-peduncled or subsessile and scarcely exceeding the subtending 

 foliage, few-many: rays short, not as long as the diameter of the head: achenes 

 short, canescent with a minute strigillose pubescence. S. Fremontii. (S. 

 blitoides Greene and S. invenustus Greene, 1. c. 123 & 124.) Among the rocks 

 in alpine stations; Colorado. 



8. Senecio Fremontii T. & G. Fl. 2: 445. 1842. Very near the preceding, 

 smaller, the stems persistently leafy to the base: leaves smaller, relatively 

 broader, often oval to 6rbicular: heads on longer peduncles distinctly sur- 

 passing the foliage. (S. Fremontii occidentalis Gray in part, not S. occiden- 

 talis Greene, 1. c., which is a plant of Nevada and California; S. occidentalis 

 rotundatus Rydb. Mem. N. Y. Bot. Card. 1: 438. 1900.) High mountains; 

 northwest Wyoming and in Idaho and Montana. 



9. Senecio triangularis Hook. Fl. Bot. Am. 1^ 332. 1834. Rather stout, 

 tflabratc; stem simple, 6-15 dm. high, bearing several or somewhat numerous 

 heads in a corymbiform open cyme: leaves all more or less petioled and 



