Senetio. . COMPOSITE. 385 



subulate bracts : involucral bracts linear-subulate, and with several loose and slender calycu- 

 late ones: rays oblong, seldom half-inch in length. — Proc. Am. Acad. vii. 362, & Bot. Calif. 

 1. c. 413. — Plains, Mendocino to Humboldt Co., California, Bolander, Kellogg, Harford. 



S. Greenei, Gray. Lightly floccose-tomentose, seldom a foot high, simple, bearing 1 to 3 

 short-peduncled heads: leaves (about inch long) coarsely dentate; radical roundish, with 

 abrupt or somewhat cuneate base, coarsely crenate-dentate, slender-petioled ; cauline few, 

 sessile, upper lanceolate and entire, sometimes all small and bract-like : heads two-thirds inch 

 long : bracts of involucre linear, no outer calyculate ones : rays deep orange, half-inch or 

 more long : style-tips of disk-flowers conspicuously penicillate-margined and with a central 

 cusp. — Proc. Am. Acad. x. 75, & Bot. Calif, i. 412. — "Wooded mountainside, near the 

 Geysers in Lake Co., California, Greene. 



S. megacephalus, Nutt. About a foot high, loosely floccose-woolly, tardily glabrate, 

 leafy : leaves entire, lanceolate, or the radical spatulate-lanceolate and tapering into a petiole, 

 and uppermost cauline attenuate, thickish (obscurely glandular under the wool?): heads 

 1 to 3, short-peduncled (8 lines to an inch high) ; involucre calyculate by some very loose and 

 setaceous-subulate elongated accessory bracts ; sometimes the true bracts and peduncles bear 

 a few hirsute hairs besides the loose wool : rays over half-inch long. — Trans. Am. Phil. Soc. 

 1. c. 410; Torr. & Gray, PI. ii. 438. — Mountains of Idaho, Nuttall, Watson, and Rocky 

 Mountains, at 5,000 to 8,000 feet, near British Boundary, Lyall, Canby. 



++ ++ Heads rayless, nodding : some sparse crisped hairs in place of tomentum : caudex hardly 

 any; the root a cluster of fibres. 



S. Bigelovii, Gray. Robust, 2 or 3 feet high, leafy up to near the racemiform or simply 

 paniculate inflorescence, pubescent with some sparse crisped hairs when young, and with 

 mere traces of arachnoid caducous wool, at length glabrate : leaves from elongated-oblong 

 to lanceolate, denticulate or more dentate, acute or acuminate ; radical and lower cauline 

 3 to 6 inches long, abrupt at base and naked-petioled, or tapering into a winged petiole or 

 partly clasping base ; upper lanceolate with partly clasping base : heads in small plants few 

 or solitary, in larger ones several, nodding on their peduncles : involucre very broadly cam- 

 pannlate ; its bracts lanceolate, thickish ; a few small and loose subulate accessory bractlets 

 at base. — Pacif. R. Rep. iv. Ill ; Porter & Coulter, PI. Colorad. 83; Rothrock in Wheeler 

 Rep. 178. With var. Hallii, Gray, Proc. Acad. Philad. 1. c. (more sessile-leaved), and var. 

 monocephalus, Rothrock, 1. c. (smallest form). — Mountains of Colorado, New Mexico, and 

 Arizona, at 8,000 to 10,000 feet ; first coll. by Bigeloiv. 



# # Heads middle-sized or small (half-inch or less). 



•J— Nodding on the paniculate pedicels in anthesis, rayless, a few loose setaceous or subulate bract- 

 lets at their base : very early glabrate or quite glabrous leafy-stemmed plants : leaves at most 

 dentate, all either petioled or attenuate at base. 



S. Rlisbyi, Greexe. Stem 2 to 4 feet high : leaves very obscurely pruinose-puberulent 

 under a lens, ovate-lanceolate, callous-denticulate ; the lower (3 to 6 inches long) with abrupt 

 or truncate base and winged petiole with dilated and somewhat auriculate half-clasping in- 

 sertion ; upper cuneately contracted into the winged petiole ; the small uppermost closely 

 sessile, attenuate-acuminate : heads (4 or 5 lines high) less nodding than in the next, almost 

 hemispherical. — Bull. Torr. Club, ix. 64, at least as to pi. Rusby. — New Mexico, in the 

 Mogollon Mountains, Rusby. Apparently in Santa Catalina Mountains, Arizona, Lemmon, 

 but specimens insufficient. Nearly related to the following : root nearly of the preceding. 



S- Cernuus, Gray. Quite glabrous, usually more slender, 2 or 3 feet high : leaves lanceolate 

 or the larger oblong-lanceolate, entire, denticulate, rarely with a few scattered coarser teeth, 

 all tapering at base into a barely margined petiole, or upper into a narrowed not clasping 

 base : heads (4 to almost 6 lines long) several or numerous in the panicle, most of them de- 

 cidedly nodding : involucre narrow-campanulate : flowers pale yellow. — Am. Jour. Sci. 

 ser. 2, xxxiii. 10 ; Porter & Coulter, PI. Colorad. 82. — Mountains of Colorado, wholly below 

 the alpine region ; first coll. by Parry. 



-f— -i— Heads erect, mostly radiate, occasionally rayless in same species. 

 ■H- Stem frutescent below. 



S. Lemmoni, Gray. Loosely much branched, early glabrate and smooth : main stems de- 

 cidedly woody: branches slender, spreading, very leafy below, nearly naked at summit, 

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