VOLUME XXVI NUMBER 7 
THE 
FoURN SE OF GEOLOGY 
OCTOBER-NOVEMBER 1918 
THE ECOLOGICAL SIGNIFICANCE OF THE EAGLE 
CREEK FLORA OF THE COLUMBIA RIVER GORGE 
RALPH W. CHANEY 
University of Iowa 
INTRODUCTION 
GEOGRAPHIC LOCATION AND TOPOGRAPHIC FEATURES OF THE COLUMBIA GORGE 
GEOLOGIC RELATIONS OF THE EAGLE CREEK FORMATION 
THE ECOLOGICAL COMPOSITION OF THE FLORA 
PHYSICAL CONDITIONS DURING THE EAGLE CREEK Epocu 
CONCLUSION 
INTRODUCTION 
During the seasons of 1916 and 1917 considerable collections 
oi fossil plant material were made by the writer in the gorge of the 
Columbia River, in Oregon and Washington. It has been planned 
to present a complete report on this material, including a descrip- 
tion of new forms, a discussion of the age of the flora, and a con- 
sideration of its ecological significance. In’ view of the possible 
interruption of this larger task a discussion of the ecological signifi- 
cance of the flora is presented in advance of the fuller report. 
Acknowledgment is made to Dr. J H. Bretz, of the University 
of Chicago, who first directed the writer’s attention to this field, 
and who is responsible for the discovery of one of the most important 
plant-bearing deposits. I am indebted also to Dr. F. H. Knowlton 
Sea 
Axsonte 
