THISTLE FAMILY 927 



Heads radiate; disk in fruit spherical or oblong. 



Leaves entire or merely toothed; plant hispid. 1. R. hirta. 



Leaves except the uppermost 3-5-cleft or pinnatifid; plant glabrous or nearly so. 



2. R. ampla. 

 Heads discoid; disk in fruit cylindraceous. 



Leaves pinnately parted. 3. R, monfana. 



LeaA'es undivided, toothed or entire. 4. R. occidenialis . 



1. R. hirta L. Perennial; stem erect, usually straw-colored, 3-5 dm. high, 

 usually purple-dotted, hirsute; lower leaves long-petioled; blades oblong-lanceo- 

 late or oblanceolate, 5-10 cm. long, entire or remotely denticulate, obtuse, 3- 

 ribbed, hirsute; upper stem-leaves linear and subsessile; peduncles 5-15 cm. long; 

 involucres 15-18 mm. high, 3-3.5 cm. broad; bracts oblong-linear, hispid; ligules 

 yellow, 1.5-3 cm. long. R.flava T. V. Moore. Hillsides and plains: Que. — Fla. — 

 Neb.— Colo.— B.C. Plain— MonL Jl-Au. 



2. R. ampla A. Nels. Perennial, with a rootstoek and thick crown; stem 

 1-2 m. high, glabrous, striate, branched above; basal leaves large, long-petioled, 

 pinnately 3-7-divided; divisions ovate or lanceolate, 2-3-cleft, and coarsely 

 serrate, glabrous and slightly paler beneath, somewhat hairy above; upper stem- 

 leaves 3-parted or entire, toothed, acuminate; involucre about 1 cm. high and 

 3 cm. wide; bracts very unequal, oblong or ovate-oblong, mostly obtuse, reflexed 

 in age, 8-12 mm. long; ligules 3-5 cm. long, 8-15 mm. wide; disk ovoid in fruit; 

 pappus coroniform, sometimes 4-toothed. Closely allied to the eastern R. lacin- 

 iata L. Wet places: Sask.—N.IM.— Ariz.— Ida. Plain— MonL Jl-Au. 



3. R. montana A. Gray, Perennial; stem 1-2 m. high, glabrous; lower 

 leaves 2-3 dm. long, petioled, pinnately parted into 3-9 oblong-lanceolate divi- 

 sions, glabrous, ciliolate on the margins; upper stem-leaves ovate or lanceolate, 

 acuminate, entire; peduncles 3 dm. long or more; involucral bracts linear, foh- 

 aceous, acute, 2-i cm. long; disk cylindric, at length 5-6 cm. long, purpUsh 

 black; pappus coroniform. Mountains: Colo. MonL Jl. 



4. R. occidentalis Nutt. Perennial; stem 5-20 dm. high, glabrous, striate; 

 leaves ovate or ovate-lanceolate, acuminate, entire or dentate, the upper sessile 

 vnth a cordate base, the lower with winged petioles, more or less hairy; peduncles 

 1-3 dm. long; bracts oblong or lanceolate, 1-2 cm. long; disk broT\Tiish black, 

 oblong, becoming 3-5 cm. long; pappus coroniform. Shaded banks: Mont. — 

 Wyo. — Utah — e Calif. — Wash. Nigger-heads. SuhmonL — MonL Jl-S. 



69. RATIBIDA Raf. Cone-flower. 



Annual, biennial, or perennial caulescent herbs. Leaves alternate, pinnatifid 

 with narrow divisions. Heads radiate, long-peduncled. Involucres many- 

 flowered, rather flat. Ray-flowers neutral; ligules yellow, or partly bro^NTi at 

 the base, rarely wholly bro^\Ti-pm-ple, spreading or drooping. Disk-flowers 

 hermaphrodite, perfect, usually enveloped by the paleae; corollas gray or yellow- 

 ish almost without a tube. Style-branches with blunt or lanceolate tips. Achenes 

 flattened, broad-margined or winged, deciduous with the scale. Pappus 1 or 2 

 teeth, or wanting. [Lepachys Raf.] 



Disk in fruit oblong, about 1 cm. long; pappus of 1-2 awn-like teeth, without intermediate 



squamellae. , , -^t. ■ j. ^" ^; '^'^ff^^^^- 



Disk in frmt cylindraceous, 2-4 cm. long; pappus with a series of squamellae. 



2. R. columnifera, 



1. R. Tagetes (James) Barnh. Perennial, with taproot; stems several, 

 branched, 2-4 dm. high, grayish-strigose; leaves pinnately divided, with 3-7 

 linear divisions, hispidulous; heads rather short-peduncled; bracts reflexed, ob- 

 lonff 3-5 mm. long; ligules 7-10 mm. long; receptacle about 1 cm. high in fruit. 

 L Tagetes A. Gray. Plains: Tex.— Kans. — Colo, — Ariz. Plain— SuhmonL Jl- 

 Au. • 



2 R columnifera (Nutt.) Woot. & Standi. Perennial, with a taproot; 

 stems often several, 3-6 dm. high, hispidulous-strigose, angled; leaves pinnately 

 divided hispidulous; divisions of the stem-leaves 5-9, oblong to linear, entire 

 or rarely 2-3-cleft; heads long-peduncled; involucral bracts oblong, 5-8 mm. 

 long soon spreading; ligules yeUow or in the variety pulchernma partly or whoUy 



