20 NORTH AMERICAN FLORA [Volume 34 



suborbicular or broadly ovate, 5-10 mm. long, mostly sinuate-dentate, scabrous-puberulent 

 and glandular-punctate; heads solitary at the ends of the branches, 30-40-flowered; involucre 

 hemispheric, 5 mm. high and about 6 mm. broad; bracts oblanceolate, boat-shaped at the base, 

 puberulent; ray-flowers 6-10; ligules yellow, broadly oval, 3 mm. long; disk-corollas nearly 

 4 mm. long; tube shorter than the tubular-funnelform throat; achenes oblong, 2.5 mm. long, 

 hirsutulous; pappus of a single awn, longer than the achenes. 



Type locality: Near Great Salt Lake, Utah [Stansbury Island]. 

 Distribution: Northern and central Utah. 

 Illustration: Stansb. Expl. Utah Bot. pi. 7. 



2. Monothrix megacephala (S. Wats.) Rydberg. 



Laphamia megacephala S. Wats. Am. Nat. 7: 301. 1873. 



A suffruticose perennial; stem scabrous-puberulent, diffusely branched, about 3 dm. high; 



leaves alternate, short-petioled ; blades thick and firm, scabrous-ovate, 4-6 mm. long, entire 



or nearly so; heads at the ends of the branches; involucre 6 mm. high, 5-7 mm. broad; 



bracts lanceolate, puberulent; ray-flowers wanting; disk-corollas 3 mm. long; tube shorter 



than the cylindro-campanulate throat; achenes hispidulous; pappus wanting. 



Type locality: Nevada. 

 Distribution: Nevada. 



3. Monothrix intricata (Brand.) Rydberg. 



Laphamia intricata Brand. Bot. Gaz. 27: 450. 1899. 



A suffruticose perennial, intricately branched from a woody base; stems numerous, 1.5-2 

 dm. high, scabrous-puberulent; leaves mostly alternate, linear-oblanceolate, about 5-8 mm. 

 long, 1 mm. wide, obtuse, hispidulous-scabrous ; heads terminating the branches; involucre 

 about 3 mm. high and 5 mm. broad; bracts linear-oblanceolate, boat-shaped below, scabrous- 

 puberulent, acute; ray-flowers none; disk-flowers about 30; corollas bright-yellow, 2 mm. 

 long; tube glandular, slightly shorter than the campanulate throat; achenes oblong, hirsu- 

 tulous; pappus wanting. 



Type locality: Pahrump, Nevada. 

 Distribution: Nevada. 



4. Monothrix Toumeyi (Rob. & Greenm.) Rydberg. 



Laphamia Toumeyi Rob. & Greenm. Am. Jour. Sci. III. 50: 176. 1895. 



A suffruticose perennial, many-branched from a woody caudex, 1-2 dm. high; branches 

 glandular-granuliferous, erect, terete, striate, rather cinereous, leafy; petioles 2-10 mm. long; 

 blades spatulate or oblanceolate, 5-15 mm. long, entire or nearly so, obtuse, thickish, ciner- 

 eous, scabrous-granulif erous ; heads discoid, short-peduncled, ending the short branches; 

 involucre campanulate, about 4 mm. high, 5-6 mm. broad; bracts about 15, linear, acute, 

 densely perberulent; disk-flowers 25-35; tube glandular, equaling the throat; achenes oblong- 

 linear, 2 mm. long, perberulent; awn solitary, 1.5 mm. long. 



Type locality: Grand Canon, Arizona. 

 Distribution: Arizona. 



5. Monothrix congesta (M. E. Jones) Rydberg. 



Laphamia congesta M. E. Jones, Proc. Calif. Acad. II. 5: 703. 1895. 



A suffruticose perennial, with a woody caudex; stems numerous, 1-2 dm. high, grayish- 



hispidulous, striate; leaves alternate; petioles about 2-5 mm. long; blades broadly lanceolate to 



broadly ovate or rhombic-ovate, 3-12 mm. long, sinuately toothed, scabrous-hispidulous; heads 



solitary at the ends of the branches, 15-20-flowered; involucre campanulate, 4-5 mm. high 



and 5-6 mm. broad, scabrous-puberulent; bracts linear-oblong, about 12, acute; rays none; 



disk-corollas 2.5-3 mm. long, cr;am-colored; tube about equaling the throat; achenes oblong, 



very scabrous-puberulent; awn solitary, equaling the achene. 



Type locality: Mesa below Buckskin Mountains, Arizona. 

 Distribution: Arizona. 



