Explanatory Note 



The series. Special Soientifio Repoirts-Flsheries, 

 embodies results of inTestigations, usually of restricted 

 scope, intended to aid or direct management or utilization 

 practices and as guides for administratire or Isgislatirs 

 action. It is issued in limited quantities for the official 

 use of Federal, State or cooperating agencies and in processed 

 form for econony and to avoid delay in publication. 



September 1949 

 Washington, D. C* 



