UNITED STATES 

 DEPARTMENT OF THE INTERIOR 

 Stewart L. Udall, Secretary 



Stanley A. Cain 

 Assistant Secretary for Fish and Wildlife and Parks 



FISH AND WILDLIFE SERVICE 

 Clarence F. Pautzke, Commissioner 



BUREAU OF SPORT FISHERIES AND WILDLIFE 

 John S. Gottschalk, Director 



North American Fauna, Number 65 



Published by 

 Bureau of Sport Fisheries and Wildlife 

 May 1968 



United States Government Printing Office • Washington • 1968 



For sale by the Superintendent of Documents, U.S. Government Printing Office 

 Washington, D.C. 20402 - Price 20 cents 



