PLATE 24 



Fig. 1. Packed sand situation in sagebrush habitat, three miles east of 

 Wallula, June 13, 1914. The plants are common sagebrush (Artemisia triden- 

 tata) and rabbit brush (Chrysottiamnus viscidiflorus and Chrysothamnus nauseosus 

 graveolens). 



Fig. 2. Drifting sand situation in sagebrush habitat, three miles east of 

 Wallula, June 13, 1914. The plants are common sagebrush and rabbit brush 

 and a few individuals of the hop sage ( Grayia spinosa). In the distance are 

 the bunchgrass-covered hills south of the Walla Walla Kiver. 



[344] 



