DESERT EVENING PRIMROSE (Oenothera trichocalyx, Nutt.). 

 Flowers showy, white with a yellow glow at the heart, turning 

 gradually to pink, 2 or 3 inches in diameter, nodding in the 

 bud, the calyx very hairy; borne on long axillary peduncles. 

 Leaves gray-green, narrow, 2 or 3 inches long, wavy-toothed 

 or somewhat lobed. The plant is an annual with white, stout- 

 ish stems. 



This Evening Primrose is one of the most charming of desert 

 wild flowers, and may be found in bloom in the spring on both 

 the Mojave and Colorado deserts of California, and thence 

 eastward to Wyoming, Arizona, and New Mexico. The plant 

 is of low habit barely exceeding 6 inches in height. The ex- 

 quisite white blossoms, which are faintly fragrant, expand in 

 the afternoon to remain open until next morning when they 

 droop and wither. 



The genus Oenothera, as originally understood, was a very 

 large one of species mostly indigenous to North America. It 

 has been one of the battlegrounds, however, of botanical 

 nomenclaturists who have sought to dismember it into a dozen 

 different parts. Advocates of latter day nomenclature de- 

 scribe our Desert Evening Primrose under the name Anogra 

 trichocalyx (Nutt.), Small. 



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