Plate XI, pP: 33% 
Harshberger, Survey N.-America. 
Association of Artemisia frigida Willd. 
Growing in the mesa region together with Argemone intermedia Sweet in the left 
foreground, Stipa Seribn, the tall grass in the center and in the background 
ucca angustifolia Pursh (= Y. glauca Nutt). 
Photograph by Dr. H.L. Shantz 
Euphorbia marginata Pursh. 
Growing on the outer margin of salt marshes in the prairie district. 
Photograph by Dr. H. L. Shantz. 
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