DEC 24 1920 



MAINTENANCE OF THE 

 FUR SUPPLY 



NED DEARBORN 



Assistant Biologist, Bureau of Biological Survey 



UNITED STATES DEPARTMENT OF AGRICULTURE 

 DEPARTMENT CIRCULAR 135 



Contribution from the Rureau of Riological Survey 

 E. W. NELSON, Chief 

 & 



Waahington, D. C. 



November, 1920 



1 



WASHINGTON : GOVERNMENT PRINTING OFFICE : 1820 



