720 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 



KEY TO THE SPECIES. 



Lobes of the disk corollas short, obtuse; leaves mostly pinnatifid . . . 1. G. pinnalifida. 

 Lobes of the disk corollas narrow, acute; leaves mostly entire 2. G. pulchella. 



1. Gaillardia pinnatifida Torr. Ann. Lye. N. Y. 2: 214. 1828. 

 Type locality: "On the Canadian ?," Colorado or New Mexico. 

 Range: Colorado to Arizona and Texas. 



New Mexico: Nearly throughout the State. Plains and low hills, in the Lower 

 and Upper Sonoran zones. 



2. Gaillardia pulchella Foug. Mem. Acad. Sci. Paris 1786: 5. pi. 1, 2. 1788. 

 Type locality: "Louisiane." 



Range: Arizona to Arkansas and Louisiana. 



New Mexico: Pajarito Park; Mogollon Mountains; Nutt Mountain; Burro Moun- 

 tains; Animas Valley; Organ Mountains; Buchanan; south of Torrance; Nara Visa; 

 Roswell. Plains and hills, in the Upper Sonoran Zone. 



98. SCHKUHRIA Roth. 



Slender, paniculately much branched annual with alternate leaves pinnately 

 parted into filiform divisions and small pedunculate heads of yellow or purplish flow- 

 ers; involucre turbinate, of 4 or 5 erect scarious-tipped bracts, 3 to 9-flowered; achenes 

 obpyramidal, the pappus of 8 scarious palese. 



1. Schkuhria wrightii A. Gray, PL Wright. 2: 95. 1853. 



Type locality: "On the Sonoita near Deserted Rancho, Sonora." 



Range: Southern New Mexico and Arizona and adjacent Mexico. 



New Mexico: Trujillo Creek; Organ Mountains. Moist canyons, in the Upper 



Sonoran Zone. 



99. HYMENOPAPPUS L'Her. 



Perennial or biennial herbs with angled erect stems, alternate, once or twice parted 

 or entire leaves, and corymbose or solitary, pedunculate heads of yellow or whitish 

 flowers; rays wanting except in one species; involucres canipanulate, many-flowered, 

 of 6 to 12 appressed bracts with scarious tips; achenes obpyramidal, 4 or 5-angled, the 

 faces 1 to 3-nerved; pappus of 10 to 20 hyaline obtuse scales. 



KEY TO THE SPECIES. 



Rays present 1. E. radiatus. 



Rays wanting. 



Basal and lower cauline leaves entire 2. E. integer. 



Basal and cauline leaves, at least most of them, pinnate or 

 pinnatifid. 

 Divisions of the leaves broadly linear to oblong or lanceo- 

 late. 



Corollas whitish; stems nearly naked 3. E. mexicanus. 



Corollas bright yellow; stems very leafy 4. E. flavescens. 



Divisions of the leaves linear or filiform. 

 Stems very leafy throughout. 



Plants permanently and densely tomentose; lobes 



of the corolla nearly equaling the throat. . . 5. E. robustus. 

 Plants glabrate in age, thinly tomentose when 

 young; lobes of the corolla much shorter 



than the throat 6. E. tenuifolius. 



Stems scapose or the leaves much reduced and few. 

 Heads 12 to 15 mm. in diameter; stems nearly 

 naked, bearing only 1 or 2 much reduced 

 leaves; stems densely arachnoid, tall 7. E. nudatus. 



