Bui. 25, Div, of Agrostology, U. S. Dept. of Agriculture. 



Plate XXIV. 



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The upper Plant, Six Weeks Grama fBouTELOUA aristidoides) ; 

 THE lower, a Drop Seed 'Sporobolus cryptandrus strictus); 

 BOTH native Arizona Grasses of considerable Importance. 



From a photograph by D. Griffiths. 



