FLOWERING PLANTS AND FERNS OF ARIZONA 977 



5. Hymenopappus pauciflorus I. M. Johnston, Grav Herbarium 

 Contrib. 68: 97. 1923. 

 Northern Apache and Navajo Counties and eastern Coconino 

 County, 5.000 to 6,200 feet, dry mesas and slopes, June to September. 

 Southern Utah and northeastern Arizona. 



91. HYMENOTHRIX 



Slender annual or perennial herbs, slightly pubescent; leaves 

 alternate, dissected into narrow divisions; heads numerous, cymose- 

 panicled, radiate or discoid, yellow, white, or purple; achenes nar- 

 rowly obpyramidal, 4- or 5-angled; pappus of 12 to 20 lanceolate 

 hyaline paleae, the costa prolonged into an awn. 



Key to the species 



1. Heads radiate, definitely yellow 1. H. wislizeni. 



1. Heads discoid, purple, white, whitish, or pale yellow (2). 



2. Petioles incurved-puberulent; lobes of the disk corollas about as long as the 



throat or a little longer 2. H. loomisii. 



2. Petioles (at least the lower ones) spreading-hirsute; lobes of the disk corollas 

 several times longer than the very short throat 3. H. wrightii. 



1. Hymenothrix wislizeni A. Grav, Amer. Acad. Arts and Sci. 



Mem. ser. 2, 4: 102. 1849." 



Hymenopappus wislizeni var. setiformis M. E. Jones, Contrib. 

 West, Bot, 12: 47. 1908. 



Cochise, Santa Cruz, Pima, and Pinal Counties, 2,400 to 5,500 feet, 

 plains, mesas, and washes, preferring sandy soil, June to December, 

 type of var. setiformis from Oracle, Pinal County {Jones in 1903). 

 Southern New Mexico, southern Arizona, and northern Mexico. 



2. Hymenothrix loomisii Blake, Biol. Soc. Wash. Proc. 40: 49. 1927. 



Hutchinsonia hyalina M. E. Jones, Contrib. West. Bot. 18: 85. 

 1933. 

 Kingman (Mohave County) to eastern and southern Yavapai 

 County, 4,000 to 5,000 feet, mesas and plains, often abundant at 

 roadsides, June to October, type of H. loomisii from Ash Fork (Loomis 

 3241), type of Hutchinsonia hyalina from Peach Springs (Mrs. Susan 

 W. Hutchinson in 1932). Known only from central Arizona. 



3. Hymenothrix wrightii A. Gray, PL Wright. 2: 97. 1853. 



Hymenopappus wrightii H. M. Hall, Calif. Univ. Pub. Bot. 3: 



179. 1907. 

 Trichymenia wrightii Rydb., North Amer. Fl. 34: 56. 1914. 



Eastern Mohave and northern Yavapai Counties to Graham, 

 Cochise, Santa Cruz, and Pima Counties, 4,000 to 8,000 feet, mostly 

 in the scrub-oak and yellow-pine belts, June to November. Southern 

 New Mexico, central and southern Arizona, southern California, and 

 northwestern Mexico. 



92. PALAFOXIA 



Annual (or perennial?) herb; leaves mostly alternate, linear or 

 lanceolate, entire; heads 2 to 2.8 cm. high, discoid, flesh-colored or 

 whitish; achenes slender, linear-tetragonal, about 1 cm. long; pappus 

 of 4 or 5 linear paleae with an excurrent nerve, or reduced in some oi 

 the flowers. 



