UNITED STATES DEPARTMENT OF THE INTERIOR 



Stewart JL. Udall, Secretary 



Frank P. Briggs, Assistant Secretary 

 for Fish and Wildlife 



FISH AND WILDLIFE SERVICE 



BUREAU OF SPORT FISHERIES AND WILDLIFE 



Daniel H. Janzen, Director 



BUREAU OF COMMERCIAL FISHERIES 



Donald L. McKernan, Director 



Fish and Wildlife Circular 97 



Published December i960 



Reprinted March 1961 



