386 COMPOSITE. Senecio. 



bearing several or numerous loosely cymose slender-pedunculate heads : leaves somewhat 

 succulent, lanceolate, irregularly and sparsely dentate with salient teeth, attenuate below and 

 with a dilated cordate-clasping base, or the lower tapering into a naked petiole ; uppermost 

 small, linear, entire: heads 4 or 5 lines high : rays about 12; disk-flowers 20 or more. 

 Proc. Am. Acad. xvii. 220. Santa Cataliua Mountains, S. Arizona, Lemmon. 



H- -H- Stems herbaceous, numerously leaf y to the top : leaves all rounded-subcordate and angu- 

 lately somewhat lobed, palinately veined and reticulate-venulose, petioled: heads small and 

 numerous in a compound cyme. 



S. Hartwegi, BEXTH. Flocculent-tomeutulose when young, or nearly glabrous : stems 2 or 

 3 feet Irish from a somewhat tuberous rootstock : leaves chartaceo-membranaceous (2 to 4 



O 



inches broad, and petiole inch or two long), the margin with 7 to S short augulate lobes or 

 coarse teeth, and sinuses denticulate : veiulets minutely reticulated : heads 3 or 4 lines long, 

 crowded: involucre iiarro \v-campauulate, 12-20-flowered ; its bracts lanceolate, short : rays 

 few. PL Hartw. 18, form with leaves tomentulose beneath. /S'. Seemanni, Schultz Bip. in 

 Seem. Bot. Herald, 311, glabrous form. Canons, S. Arizona, near Fort Iluachuca, Lemmon. 

 (Mex.; of a Mexican type unlike any other N. American.) 



H. -H. ++ Stems numerously and nearly equably leafy to the top : leaves pinnately veined, not con- 

 spicuously reticulated, from entire to laciniate-denlate, never divided or dissected, nor narrowly 

 linear: glabrous, or very early glabrate and smooth, seldom a vestige of wool at anthesis. 



= Low, alpine: heads subsolitary, radiate. 



S. Fremonti, TOUR. & GRAY. Many-stemmed from a thickish caudex, a span to a foot 

 high: leaves thickish, from rounded-obovate or spatulute to oblong (inch or sometimes 

 2 inches long), obtuse, obtusely or acutely dentate, sometimes even pinnatifid-deutate, lower 

 abruptly contracted into a winged petiole; uppermost sessile by broadish base: heads half- 

 inch high, short-peduncled, subtended by a few short loose bractlets : rays 3 to 5 lines long. 

 Fl. ii. 445. Alpine region of the Rocky Mountains (first coll. by Fremont), from near 

 Brit, boundary to S. Colorado, Utah, and Lassen's Peak, California : passing to 



"Var. occidentalis, GKAY. More slender, with rounder leaves and heads longer- 

 peduucled ; in high alpine stations becoming very dwarf, and flowering almost from the 

 grouud. Bot. Calif, i. 618. Sierra Nevada, California, at 10,000 to 12,000 feet, Rothrock, 

 &c. Also Rocky Mountains of N. Wyoming and Montana, at 7,000 to 8,000 feet, Lyall, 

 Parry, very dwarf. 



= = Rather low, with numerous cymosely paniculate and small heads, always rayless. 



S. rapifolius, NUTT. About a foot high : leaves ovate or oblong, throughout very sharply 

 and unequally dentate, rather fleshy ; radical tapering into a petiole, cauline mostly clasping 

 by a broad subcordate base : heads 3 lines high, about 15-flowered : involucral bracts 8 to 10, 

 narrowly oblong. Trans. Am. Phil. Soc. vii. 409: Torr. Gray, Fl. ii. 441. Rocky 

 Mountains, Wyoming, about the sources of the Platte, Nuttall, Fremont, &c. 



= = = Tall, with corymbosely cymose and radiate heads : involucre setaceously few-bracteo- 

 late, campanulate or narrower: leaves nearly membranaceous. 



S. triangularis, HOOK. Rather stout : stem simple, 2 to 5 feet high, bearing several or 

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

 thickly dentate (sometimes minutely so, sometimes with long lanceolate-subulate and very 

 salient teeth), deltoid-lanceolate, or the lower triangular-hastate or deltoid-cordate, and upper- 

 most lanceolate with cuneate base : heads about half-inch high : involucre campanulate, 

 mostly 25-30-flowered ; the oblong-linear rays 6 to 12. Fl. i. 332, t. 115; Torr. & Gray, Fl. 

 ii. 441 ; Eaton, Bot. King Exp. 189 ; Gray, Bot. Calif, i. 414. 5. longidentatus, DC. Prodr. 

 vi. 428. Wooded districts in wet ground, Saskatchewan to Washington Terr., south to the 

 higher mountains of Colorado and through the Sierra Nevada, California. 



S. Huachucanus, GRAY. Two or three feet high, somewhat branching: leaves ovate- to 

 oblong-lanceolate, acuminate, minutely denticulate; lower cauline (4 to G inches long) taper- 

 ing into a winged petiole, upper partly clasping by a broad subcordate base: heads fastigi- 

 ately cymose, small, about 4 lines high : involucre cylindraceous-campanulate, 1 5-18-flowered : 

 the small rays 3 or 4. Proc. Am. Acad. xix. 54. High bluffs near Fort Iluachuca, S. 

 Arizona, Lemmon. 



S. serra, HOOK. Strict, 2 to 4 feet high, very leafy, sometimes simple and bearing rather 

 few somewhat large (half-inch long) heads, commonly branching at summit, then bearing 



