COMPOSURE. (COMPOSITK FAMILY.) Km 



pappus copious and simple, of rather rigid and unequal bristles: leafy- 

 stemmed and hranchimj, the s/iowi/ heads terminatimj the branches, the invo- 

 lucre canescent or even viscid, and the leaves frum dentate to ljijiinnateli/-parted. 

 — Mach^ranthera. 



* Involucre denseli/ hispidulous as well as viscid, veri/ sfjuairose: akenes (da- 



brous or fjlalrate: leaves from inciseli/ dentate to entire, the tieth hardli/ at all 

 bristle-ti/i/K <l : rai/s hrifjht violet. 



36. A. Patterson!, Gray. A span or two high, branched frum the summit 

 of the tap-root : stems or branches with soft or cottonij pubescence or glahrate : 

 leaves thickish, spatulate or Inifjulale, entire or coarseli/ few-toothed, none widened 

 at base: heads solitary or few: mvolucrul bracts lanceolate: rays about 30, 

 fully ^ inch long. — Proc. Am. Acad. xiii. 272. Machnranthera canescms, 

 var. cdpina. Porter, Fl. Colorad. 59. Moist ground along streams, Ci ray's 

 Peak, Colorado. 



37. A. Bigelovii, Gray. A foot or two liigh, robust : stem leafy, branch- 

 inr/ above, rouf/hlsh-hnsute to ylabrate; the fuwering branches or peduncles glandu- 

 lar-hirsute, terminated by showy large heads : leaves oblong or lanceolate, 

 irregiilarlij and sometimes maseli/ dentate, sometimes entire; radical lanceolate- 

 spatulate ; cauline oblong to lanceolate, usually ivith broadish parti y clas/nng 

 base : involucral bracts very numerous, linear-attenuate or the prolonged and 

 much recurved tips almost filiform : rays very many, an inch or less long. — 

 Pacif. R. Rep. iv. 97. Colorado and New Mexico. 



* * Involucre from nearlg glabrous to glandnlar-puberulent, but not hispidulous : 

 akenes densely pubescent or vUlous: leaves generally with bristle-tijiped teeth. 



H- Leaves at most incisely dentate. 



38. A. Coloradoensis, Gray. A span or le.ss high, forming a tup of 

 short fn--leaved stems on a strong tap-root, canescently j)ube.scent, not at all 

 glandular : leaves spatulate or obianceolate, about an inch long, coarselij den- 

 tate, the teetli tipped with conspicuous bri.stles : heads solilan/, broadlv hemi- 

 splierical, ^ inch high : involucral bracts small and numerous, well imbricated, 

 subulate-lanceolate: rays 35 to 40, violet-inirple, l)arely ^ inch long: akenes 

 densely canescent-villous, ^ the length of tlie comparatively rigid pappus. — 

 Proc. Am. Acad. xi. 76. Common in South Park, Colorado, and at the Sau 

 Juan Pass, 



39. A. caneseens, Pursh. Commonly a foot or two higli and loosely 

 much branched, bearing numerous paniculate heads, sometimes dwarf and with 

 simple contracted inflorescence, pale and cinereous-pubcrnlent or minutely 

 canescent, or greener and glahrate : leaves lanceolate to linear, or the lower 

 spatulate, from entire to irregularly dentate, or occasionally lacniiatc, tiie rigid 

 teeth mostly with mucronate tip : involucre of rigid usually well-inibricatcd 

 bracts: rays violet, 4 or 5 lines long: akenes narrow, canescent. — Fl. ii. 547. 

 Machiiranfhera caneseens and M. p\ilverulenta of the Western Reports A 

 polymorphous species. From Arizona to Texas and northward to British 

 ColiimI)ia and the Saskatchewan. 



Var. latifolius, Cirny. Green, minutely soft-pubescent. 2 foot t)r more 

 high : leaves thinnish, nearly membranaceous, comparatively large, some- 

 times spatulate-oblong, and over ^ inch wide: heads large ami few: involucre 

 hemis])bcrical ; tips of its bracts mostly attenuate-subulate and ,s(|uarro<»e- 



