Southeastern Washington and Adjacent Idaho. i 
not reported for the region were encountered. Among these the 
occurrence of the devil’s club, Echinopanax horridum, along cer- 
tain streams in Thatuna Hills, is especially interesting. Many 
of the species new to the region are ruderals. Other plants like 
Crataegus columbiana piperi, heretofore known to occur only in 
Washington, were also repeatedly found in Idaho. 
It is hoped that the results of the present research may form 
a basis for further investigation of the ecological problems of 
this and adjoining regions. 
LITERATURE CITED 
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central Washington. Water-supply paper U. S. Geological Survey 
No. 118, 1905. 
2. Clements, F. E. Plant Succession. Carnegie Inst. Wash. Publ., 242, 
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3. Frye, Theodore C., and Rigg, George B. Northwest Flora, 1912. 
4. Fuller, George Damon. Evaporation and Plant Succession. Bot. Gaz., 
52: 193-208, IQII. 
5. Fuller, George Damon. Evaporation and Soil Moisture in Relation 
to Succession of Plant Associations. Bot. Gaz., 58: 193-234, I9I4. 
6. Humphrey, Harry B., and Weaver, John Ernst. Natural Reforesta- 
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ington and Adjacent Idaho, 1914. 
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1k3 
