660 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 



Range: Idaho and Minnesota to New Mexico and Texas. 



New Mexico: Tunitcha Mountains; Aztec; Carrizo Mountains; Chama; south of 

 Gallup; Santa Fe; Las Vegas; Hermits Peak; Organ Mountains; Dona Ana Mountains; 

 Tortugas Mountain; west of Roswell; Gilmores Ranch. Dry hills and plains, in the 

 Upper Sonoran and Transition zones. 



7. Chrysopsis hirsutissima Greene, Pittonia 4: 153. 1900. 

 Type locality: Arboles, southern Colorado. 



Range: Colorado and NeAV Mexico. 



New Mexico: Santa Fe; Ensenada; Tesuque; Laguna; James Canyon; Wingfields 

 Ranch. Dry hillsides, in the Upper Sonoran and Transition zones. 



8. Chrysopsis hispida (Hook.) Nutt. Trans. Amer. Phil. Soc. n. ser. 7: 316. 1841. 

 Diplopappus hispidus Hook. Fl. Bor. Amer. 2: 22. 1834. 



Chrysopsis villosa hispida A. Gray, Proc. Acad. Phila. 1863: 65. 1864. 



Type locality: " Carlton-House Fort." 



Range: Saskatchewan and Alberta to Arizona and New Mexico. 



New Mexico: Farmington; Tunitcha Mountains; Dulce; mountains west of Grants 

 Station; Upper Pecos; Pajarito Park; Santa Fe; Las Vegas; Sandia Mountains', Laguna; 

 Sierra Grande; Water Canyon; Tortugas Mountain; White Mountains; Gray; mountains 

 west of San Antonio. Plains and dry hills, in the Upper Sonoran and Transition 

 zones. 



18. CHRYSOTHAMNUS Nutt. Rabbit brush. 



Coarse plants, usually shrubby, sometimes woody only at the base, 30 cm. to 2 

 meters high, with entire narrow leaves, and usually corymbose small heads of yellow 

 flowers; heads narrow, cylindric or turbinate, mostly 5-flowered; involucre of narrow 

 keeled dry bracts, these often with spreading tips, arranged in 5 vertical ranks; 

 achenes slender, glabrous or pubescent; pappus of nearly equal bristles. 



A decoction of the heads of various species of Chrysothamnus was formerly used by 

 the Navahos in dyeing wool yellow. 



key to the species. 

 Achenes glabrous. 



Stems, leaves, and involucres more or less floccose 1. C. bigelovii. 



Plants without floccose pubescence. 



Involucres about 5 mm. high, the bracts not acuminate.. 2. C. vaseyi. 

 Involucres 10 mm. high or more, the bracts usually 

 abruptly acuminate. 



Leaves oblanceolate or nearly so, puberulent 3. C. depressus. 



Leaves mostly linear, usually glabrous except on 

 the margins. 

 Leaves ciliolate; heads, including the pappus, 



less than 15 mm. long 4. C. baileyi. 



Leaves not ciliolate; heads 20 mm. long or more. 

 Leaves densely puberulent on the faces; 

 tall shrub 75 cm. high; bracts acu- 

 minate 17. C. elalior. 



Leaves glabrous on the faces; low shrub 30 

 cm. high or less; bracts not acumi- 

 nate 5. C. pulchellus. 



Achenes pubescent. 



Plants entirely glabrous or at least never tomentose. 

 Bracts obtuse or acutish. 



Leaves linear, twisted 6. C. elegans. 



Leaves linear-lanceolate, not twisted 7. C. glaucus . 



