FLOWERING PLANTS AND FERNS OF ARIZONA 979 



3. Eriophyllum pringlei A. Gray, Amer. Acad. Arts and Sci. Proc. 19: 



25. 1883. 



Actinolepis pringlei Greene, Fl. Francisc. 441. 1897. 



Yucca (Mohave County) and in Maricopa and Pima Counties, 

 1,500 to 3.000 feet, gravelly mesas and slopes, March to May. South- 

 ern Nevada, western and southern Arizona, and southern California. 



4. Eriophyllum wallacei A. Gray, Amer. Acad. Arts and Sci. Proc. 19: 



25. 1883. 

 Bahia wallacei A. Grav in Torr., U. S. Rpt. Expl. Miss. Pacif. 



4: 105. 1857. 

 Anthe/opeas wallacei Rydb., North Amer. Fl. 34: 98. 1915. 

 Valentine to Chloride and Oatman (Mohave County), 3.000 to 

 4.000 feet, mesas and plains, March to June. Southern Utah and 

 western Arizona to southern California. 



5. Eriophyllum lanosum A. Grav, Amer. Acad. Arts and Sci. Proc. 



19:25. 1883. 



Burrielia lanosa A. Grav in Torr., U. S. Rpt. Expl. Miss. Pacif. 



4: 107. 1857. 

 Antheropeas lanosum Rydb., North Amer. Fl. 34: 98. 1915. 



Northern Mohave County to Pinal, Pima, and Yuma. Counties. 

 1,200 to 3.000 feet, dry gravelly mesas and slopes, common, February 

 to May. Southern Utah, southern Nevada, western Arizona, south- 

 eastern California, and Baja California. 



94. CHAEXACTIS" 



Low herbs; leaves alternate, entire to bipinnatifid, the blade or 

 its divisions narrow; heads flesh-colored or white, discoid but some- 

 times with enlarged outer corollas; achenes linear; pappus of hyaline 

 paleae, these without a midrib. 



Key to the species 



1. Phyllaries attenuate into pale, almost aristiform tips: plant scurfy-puberulent, 

 not tomentose or glandular: receptacle with some setaceous pales. 



1. C. CARPHOCLINIA. 



1. Phyllaries obtuse to acuminate, but not attenuate into aristiform tips; plant 



tomentose or glandular, at least when young: receptacle naked (2 . 



2. Leaves entire and linear, or once pinnatifid, with few unequal lobes; plants 



soon glabrate (3). 



3. Involucre 8 to 10 mm. high, the phyllaries not loose-tipped; pappus of 



4 usually equal paleae, these in a single series; marginal corollas 



decidedly larger than the others 2. C. fremoxti. 



3. Involucre normally 12 to 17 mm. high, the phyllaries usually loose-tipped; 



pappus of 4 long paleae and 4 very short outer squamellae: marginal 



corollas not definitely larger than the others 3. C. xaxtiaxa. 



2. Leaves (at least the lower ones) bipinnatifid, with usually numerous lobes, 

 more or less persistently tomentose (4 s ) . 



4. Involucre 10 to 15 mm. high; anthers not exserted: pappus of 4 paleae and 



2 to 4 very short outer squamellae; outer phyllaries with loose tips. 



4. C. MACRAXTHA. 



4. Involucre 6 to 9 (rarely 12) mm. high: anthers exserted: pappus oi 4 

 to 8 paleae, these sometimes unequal but not 2-seriate; outer phyllaries 

 scarcely loose-tipped (5). 

 5. Pappus of 4 paleae; plant annual: outer corollas distinctly larger than 



the others 5. C. stevioides. 



5. Pappus of about 8 paleae; plant perennial or biennial; outer corollas 

 not enlarged 6. C. douglasii. 



-Reference: Stockwell, Palmer, a revision of the genus chaenactis. Contrib. Dudlev Herb. 

 Stanford Univ. 3: 69-167. 1940. 



