378 CARDUACEAE. 



ranch; Stove Prairie; Granite; Ouray; Ruxton Park; foot of Mt. Harvard; 

 hills about Box Canon, west of Ouray ; mountains, Larimer Co. ; North 

 Cheyenne Canon; mountains between Sunshine and Ward; Durango; Horse- 

 tooth Mountain ; foot-hills, Larimer Co. ; Elk Canon ; Idaho Springs ; Em- 

 pire; Gray's Peak; Lake City; headwaters of Clear Creek. 



66. CHAENACTIS DC. 



Annuals. i. C. stevioides. 



Perennials. 



Heads corymbose, short-peduncled ; caudex short, erect. 2. C. Doiiglasii. 



Heads solitary, rather long-peduncled ; caudex with spreading branches. 



Bracts equalling the disk, only slightly tinged with purple. 3. C. pedicularia. 

 Bracts much shorter than the disk, purplish. 4. C. alpina. 



1. Chaenactis stevioides H. & A. In arid places from Ida. and Nev. to 

 N. M. and Ariz. — Alt. 4000-6000 ft. — Hotchkiss ; Rifle; McElmo Cafion ; 

 Grand Junction ; Delta Co. ; Palisades. 



2. Chaenactis Douglasii H. & A. In sandy and rocky places from Mont, 

 and Wash, to Colo, and Calif. — Alt. 6000-9000 ft. — High rocks, Middle Park; 

 North Park ; Leroux, Delta Co. ; Twin Lakes ; Doyle's ; Cimarron ; head- 

 waters of Sangre de Cristo Creek ; Grand River Canon ; piiion belt, north 

 of Mancos ; Grayback mining camps and Placer Gulch ; Palisades ; Elk River, 

 Routt Co. 



3. Chaenactis pedicularia Greene. On high mountains of Colo. — Alt. about 

 11,500 ft. — Como; Little Kate Mine, La Plata Mountains. 



4. Chaenactis alpina (A. Gray) Jones. (C. Douglasii alpina A. Gray) On 

 high mountains from Mont, to Colo, and Utah. — " Colorado." 



67. TETRANEURIS Greene. 



Flowering stems scapiform, leafless. 



Leaves densly appressed silky, at least when young. 

 Leaves not strongly 3-nerved on the broadened bases. 



Leaves spatulate or oblanceolate, 2-4 cm. long; scape 2-12 cm. high. 



1. T. acaulis. 

 Leaves linear or linear-oblanceolate ; scape 12-20 cm. high. 



2. T. simplex. 

 Leaves strongly 3-nerved on the broadened bases, narrowly oblanceolate. 



3. T. trinervata. 

 Leaves loosely villous or glabrate. 



Leaves, scapes and involucres decidedly long-villous. 4. T. lanata. 



Leaves glabrous or sparingly villous ; scape finely pubescent (long-villous 

 only in T. Torreyana). 

 Branches of the caudex copiously villous at the ends, with long, at first 

 white, but later brownish hairs. 

 Pappus-scales lanceolate, acute ; bracts oblong. 



Crowns of the caudex copiously villous; scape 5-10 cm. long. 



5. T. Torreyana. 

 Crowns of the caudex not copiously villous ; scape 1-2 cm. high. 



6. T. brevifolia. 

 Pappus-scales oval, awned. 



Leaves oblanceolate, hairy. 7. T. arizonica. 



Leaves linear-oblanceolate, or linear-oblong, glabrate. 



Bracts oval. 8. T. pilosa. 



Bracts linear-oblong. 9. T. LrandalUi. 



