914 MISC. PUBLICATION 4 2 3, U. S. DEPT. OF AGRICULTURE 



Key to the species 



1. Plant 50 cm. high or more, erect, branched only above; stem below glabrous or 

 hirsute; leaves mostly entire or merely toothed 1. P. asteroides. 



1. Plant usually about 30 cm. high or less, diffusely branched from the base; stem 

 glandular-hispidulous throughout, usually also somewhat pilose; leaves 

 mostly laciniate-pinnatifid with spinescent-tipped lobes, sometimes merely 

 toothed 2. P. coulteri 



1. Psilactis asteroides A. Gray, Amer. Acad. Arts and Sci. Mem. ser. 



2, 4: 72. 1849. 



Aster boltoniae Greene, Pittonia 3: 248. 1897. 



Woodruff (Navajo County), Tuba (Coconino County), south to 

 Cochise and Pinal Counties, 1,400 to 5,000 feet, river bottoms, 

 marshes, and roadsides, June to October. Southwestern Texas to 

 Arizona and central Mexico. 



2. Psilactis coulteri A. Gray, Amer. Acad. Arts and Sci. Mem. ser. 2, 



4: 72. 1849. 

 Pinal, Pima, and Yuma Counties, 200 to 2,400 feet, river bottoms 

 and roadsides, February to October. Southern Arizona, southern 

 Nevada, southeastern California, and Sonora. 



25. MONOPTILON 



Dwarf hispid-hirsute winter annuals, diffusely branched; leaves 

 linear-spatulate, small, entire, the upper ones subtending the solitary 

 heads; rays white or rose-tinged, often drying bluish; disk yellow; 

 involucre broad, nearly 1 -seriate, the phyllaries equal, subherbaceous, 

 scarious-margined ; achenes obovate-oblong, compressed, 2-nerved; 

 pappus of numerous unequal bristles or narrow paleae, or of a scarious 

 cup and a single subplumose bristle. 



Key to the species 



1. Pappus of numerous unequal bristles, or of bristles and short narrow paleae. 



1. M. BELLIOIDES. 



1. Pappus of a scarious cup and a single subplumose bristle. 



2. M. BELLIDIFORME. 



1. Monoptilon bellioides (A. Gray) H. M. Hall, Calif. Univ. Pub. 



Bot. 3: 75. 1907. 



Eremiastrum bellioides A. Gray, Amer. Acad. Arts and Sci. 

 Mem. ser. 2, 5: 321. 1854. 



Mohave, Maricopa, Pinal, Pima, and Yuma Counties, 200 to 3,500 

 feet, sandy or stony mesas and slopes, February to April. Southern 

 Utah, Arizona, southern California, and Sonora. 



2. Monoptilon bellidiforme Torr. and Gray in A. Gray, Boston Soc. 



Nat. Hist. Proc. 1: 210. 1845. 

 Fort Mohave, Mohave County (Lemmon in 1884, mixed with M. 

 bellioides), 500 feet, April. Southwestern Utah to southeastern 

 California and western Arizona. 



26. TOWNSENDIA es 



Low perennial, or rarely annual or biennial herbs ; leaves spatulate 

 to nearly linear, entire; heads medium-sized or rather large, Ulster-like, 



«s Reference: Larsen, E. L. a revision of the genus townsendia. Mo. Bot. Gard. Ann. 14: 1^6. 

 1927. 



