Toimsendia. COMPOSITE. 169 



large-headed, comparatively broad-leaved, and glabrate forms (which may almost pass into 

 the two preceding species), to a narrowly leaved and more sericeous form with head barely 

 two-tliirds inch long, as in tlie original northern specimens (botli grow together in Colorado, 

 " the latter flowering two weeks later"), or sometimes even yet more reduced, so that the 

 heads are barely liall'-inch long. 



Var. leptotes, Gray, is an 'ambiguous form from Middle Park, Colorado (Parrij), 

 with heads less tlian half-inch long, and all but the primary ones somewhat distinctly pedun- 

 culate : leaves narrowly linear with attenuate base. Perluxps a distinct species. 



T. Arizonica, Gray. Depressed subcaule.scent and multicipital, or branching from a per- 

 ennial root, forming a lax pulvinate tuft of 2 or 3 inches high, minutely sericeous-canescent : 

 leaves spatulate, short (about lialf-inch long), seldom surpassing tlie barely sessile and mostly 

 foliose-fulcrate liemispherical heads (these merely half-incli high) : bracts of the involucre 

 lanceolate, mostly obtuse : pappus of ray and disk alike and of ecpial length, rather rigid, about 

 the length of the akene (2 or 3 lines long). — Proc. Am. Acad. xvi. 85. — Arizona, adjacent 

 Utah (Palmer), and N. W. New Mexico, Coues & Palmer, M. E. Jones, Matthews. 



T. incana, Nutt. Depressed-caulescent or subcaulescent from a winter annual or perennial 

 root, an inch to a span liigh, branching, strigulose-cinereous or canescent : leaves from nar- 

 rowly spatulate to almost linear; uppermost fulcrate around the sessile (about half-inch) 

 heads and seldom surpassing them : involucral bracts more sericeous and ciliate and less 

 obtuse than in the foregoing : pappus of the ray from a third to half tlie length of that of 

 the disk. —Trans. Am. Phil. Soc. 1. c. T. Fremontii, Torr. & Gray, in Jour. Bost. Nat. Hist. 

 Soc. v. 108, where the heads are wrongly said to be larger than tliose of T. sericea. — 

 Mountains of Wyoming to S. Utah and the borders of S. Nevada; first coll. by Nuttali. 

 +++++-!• Heads about one-third inch lonj^, sessile among the rosulate leaves: herbage soft- 

 lanate: pappus deciduous in a ring! — § Umphorns, Nutt. 



T. spathulata, Nutt. Depressed and multicipital from a slender perennial root, forming 

 a tuft an inch or so high : leaves crowded, spatulate, densely villous-lanate ; the upper about 

 equalling tiie heads : bracts of the involucre oblong-lanceolate, acute : rays rather short, 

 pinkish : pappus of ray and disk similar and of the same length, of slender bristles, — 

 Trans. Am. Phil. Soc. 1. c. — Rocky Mountains in Wyoming; ou the Black HiUs of the 

 Platte, Nuttnll, and Wind-Kiver Mountains, Parry. 



++++++++ Heads small, only a quarter-inch high (exclusive of the rays), mostly short-pedun- 

 culate, hemispherical: involucre of few-ranked broadly lanceolate and barely acute bracts: 

 caulescent and branching (at least in age) and suninier-tiowcring: pappus of the (sometimes 

 infertile but feminine) ray shorter, commonly setose-squamellate. 

 = Green and glabrate, perennial. 



T. glabella, Gray. An inch or two high from a slender rootstock, nearly simple, sparsely 

 pilose-pubescent when young : leaves thickish, soon glabroirs, spatulate (an inch or less long, 

 including the u.sually .slender petiole); the uppermost usually surpassed by the slender and 

 naked (sometimes inch-long) peduncle : involucre glaln-ons : pappus of the ray in one speci- 

 men plurisetose and nearly half tlie length of that of the disk, in another reduced to short 

 squamellffi. — Proc. Am. Acad. xvi. 86. — Pagosa, S. W. Colorado, Neirbcrrij. 

 = = Cinereous with fine and close somewhat strigulose pubescence, flowering from near the 

 ground at first, but becoming taller (4 to 10 inches liigh) and h)Osely brandling: pappus of ray- 

 akenes always reduced to a crown of short squamellje, witli rarely one or two short bristles. 

 (Species hardly distinct.) — § Nanodia, Nutt. 



T. Fendleri, Gray. Root slender, but apparently perennial ■ leaves linear ; bracts of the 

 involucre unequal, in about 3 ranks, acute. — PI. Fendl. 70, & Proc. Am. Acad. 1. c — 

 Gravelly hills. New Mexico and S. Colorado, fl. May to Sept. ; first coll. by Femller. 



T. strigosa, Nutt. Winter annual, with slender root, flowering when only half-inch high, 

 often attaining a span in height : early leaves spatulate , later ones linear : heads rather 

 smaller : bracts of the involucre broader, acuti.sh, in about 2 ranks, the outer shorter. — 

 Trans. Am. Phil. Soc. 1. c. ; Gray, PI. Fendl. 1. c. — Gravelly hills and plains, Wyoming to 

 New Mexico and Arizona ; first coll. by Nuttali. 

 T. MexicAna, Gray, PI. Fendl. 70 (from about Saltillo, &c., Mexico, Greijg, Parnj, Palmer, 



and from farther south, Galeotti), differs slightly from the last in having the two ranks of 



involucral bracts of equal length and all very obtuse. 



