598 COMPOSITAE (COMPOSITE FAMILY) 



106. TROXIMON Nutt. 



Herbs, mostly acaulesoent, with tufted usually sessile basal lea,YBS and 

 solitary heads of yellow or rarely purple flowers at the end of a naliedor 

 bracted scape. Involucre campanulate or oblong, the bracts imbricated in 

 several rows, appressed or with spreading tips, i membranous or herbaceous, 

 not thickened after flowering, the outer ones gradually shorter and broader. 

 Receptacle flat, naked or foveolate. Rays truncate and 5-toothediat .the 

 apex. ' Anthers sagittate at the base. Style-branches slender, f ijiehenes 

 oblorig, obovate, or linear, 10-ribbed, not flattened, beaked at the summit. 

 Pappus of copious, slender, simple, white bristles. ,. , i 



Achenes tapering to a stout-nerved beak shorter than the body; 

 flowers yellow, often roseate in drying. 



Leaves entire or coarsely and irregularly toothed. - i i ■ i ■ . . 



Leaves more or less pubescent even in age.; , ..,■,■. n 

 Narrowly ^lanceolate or linear, and often somewhat laciniate- 



toothed . . .[,','.' " '. '.' 1'. T.pubesrieHS. 



Lanceolate ot oblanceolate, often broadly so and obtuse . ■ ' 2. TiVillosuid. i . ■ 



Leaves glabrous at least in age; the involucre glabrous or some- ,,.,., 



what pubescent. . i ^ , j 



Leaves not 2-ranked . . .'.''. . .' - '. 3. -Tj glAubiun. 



Leaves 2-ranked, linear .'- : ■ . .'.''-■. 4. -T. parviflorum. ' 



Leaves narrowly linear, or latoiniately parted into linear divisions ., - 6. T. araGhnQi<^eum. 

 Achenes with slender beak, as long as or longer than the body. 

 Flowers orange, in ace or oh drying oftenput^plish; more or less 



woolly-pubescentunder the involucre. ' - 



Plant lov'(l-2 dm.); leavcjs tapering to a short-winged petiole, , • ! i ■ i 



or sessile ,.,.,. . . . . . . 6. T. aurantiacum. , 



Plant taller ,(2-5 dm.); leaved tapering into a long, slender, ' !' ' 

 ' wiriged petiole . . . ■; . . . ,7. T. purpur^um. 



Flowers yellow, scarcely changing, when dry. , , ,i 

 Involucre glabrous. 



Somewhat woolly-pubescent below the involucre on the '''''' 



peduncle . . . . ... . . 8. T. arizonicum. 



Not woolly-pubescent on the peduncle '^;i ii' . : '.. 9. T. elatum.. 



Involucre more or less pubescent ...... 10. T. montanum. 



1. Troximon pubescehs (Rydb.) A. Nels. Perennial with a taproot and 

 short, branching caudex: leaves narrowly oblanceolate, about 1 dm. long, 

 5-15 mm. wide, acuminate, slightly slaucous but even in age villous-^pubescent; 

 acape 1.5-3 dm. high, sparingly villous: involucre about 2 cm. high, villous 

 and somewhat viscid; bracts with a dark median line and sometimes tinged 

 with purple, the outer ones ovate-lanccolatc, about two thirds the length of th^ 

 linear-lanceolate, long-acuminate inner ones: flowers yellow, the outer pfte'ii 

 striate or tinged with purple: beaks of the achenes short and striate through- 

 out. (Agoseris pubescens Rydb. Bull. Torr. Bot., Club 28: 511. 1901;^. 

 attenuata Rydbi 1. c. 32: 136. 1905.)— In the foothills; Wybming and'Colo- 

 rado. , ' 



2. Troximon villpstim ,(Rydb.) A. Nels. Leaves oblanceolate, more 6r less 

 fiubescent, especially on the margins and veins; scape ,1-2 din. high, often 

 sparingly hairy and villous under the head: involucre campanula tej about 2 

 cm. high; outer bracts ovate or ovate-lanceolate,- more orless villous especially 

 on the margins, dotted with blackish dots; inner bracts lanceolate: hgules 

 yellow or the outer tinged with reddish: achenes with a short striate beak. 

 (Agoseris vitlosa Rydb. Mem. N. Y. Bot. Gard^ 1: 458. 1900; A. fiiafiutata 

 Rydb. Bull. Torr. Club,32: 136. 1905, the original description of which is 

 here used.) — Colorado to Montana. '" i 



3. Troximon glauciuu J^^utt. Gen. 2: 128. 1818. Perennial, pale or' glau- 

 cous, glabrous throughout or a little woolly below: leaves linear, lanceolate, 

 or oblong, entire, dentate, or pinnatifid, i5-25 cm. long, 4-20 mm. wide, acu- 

 minate at the apex, nari-oyed at tihe'base, sometimes into margined petioles; 

 scapes stout, glabrous or' slightly pubescent, longer, than the leaves, ofteii 

 4 dm. high: involucre oblong-campanulate, or broader in fruit, cbmmohly 

 quite glabrous, the bracts lanceolate, acuminate: achenes conspicuously 

 beaked; pappus of rather rigid, scabrous or denticulate bristtes. , (T.' rpseum 

 Nutt. Trans. Am. Phil. Soc' 7: 434. 1S41; see also Greene, Pitt. 2: 77 & 176 



