6 PREFACE 



Dr. Fred Powell of the Brookings staff has from time to 

 time made invaluable suggestions both as to the method of 

 approach and technique of procedure. I owe him a debt 

 which no mere line in the preface can repay. To Dr. Lev- 

 erett Lyon, who in his official capacity as Director of Fel- 

 lows at the Institution, made it possible for me to obtain 

 access to important materials in Washington, and to other 

 members of the staff, I am under similarly deep obligation. 



Much of the material found in the first chapter was 

 gathered during the summer of 1934 as a result of a study 

 made while serving as Associate Consultant for the National 

 Resources Board, under the direction of Mr. Charles Eliot, 

 2nd, the executive secretary. 



I should also like to express my appreciation for the 

 assistance of my colleagues, Mr. Charles Trinkaus and Mr. 

 William Shaughnessy, in reading proof. 



Limitations of space make it impossible to express my 

 appreciation individually to the men and officers of the 

 United States Biological Survey, Bureau of Fisheries, For- 

 est Service, Bureau of Indian Affairs, Bureau of Reclama- 

 tion, and the Minnesota Game and Fish Department for 

 their generous co-operation; I take this opportunity there- 

 fore to do so collectively. 



R. H. C. 



