Oed 31. LOASACEA 



1. MENTZELIA, Linn. 



1. Mentzelia albicaulis, Dough 



Hab. Interior of Washington Territory; in prairies; extending 

 southward to San Diego in California, and eastward to Texas. — Stem 

 more or less smooth, the lower part usually (but not always) whitish 

 and shining. Leaves varying from deeply sinuate-pinnatifid to re- 

 motely toothed. Lobes of the calyx lanceolate. Petals obovate; 

 very obtuse. Filaments about 15, very slender. Capsule about an 

 inch long, and a line and a half in diameter. Seeds rhombic-cuboid ; 

 minutely scabrous. 



2. Mentzelia l^evicaulis, Dough 



Hab. On the Klamath River, Northern California; and Walla- 

 Walla, Oregon. — According to Mr. Brackenridge, who collected the 

 specimens, the flowers are of a "pale-yellow color." Sir William 

 Hooker unites this species with M. ornata; but it differs, according 

 to Dr. Gray, in its yellow flowers, which open in the afternoon in 

 bright sunshine, while those of M. ornata open near sunset, and re- 

 main expanded through the evening. Vid. Gray, PI. Fendl. p. 47, 

 and PL Wright, Part 1, p. 73. 



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