LETTER OF TRANSMITTAL, 



United States Department of Agriculture, 



Bureau of Biological Survey, 

 Washington, D. C, Odoler 21, 1914. 

 Sir: I have the honor to transmit herewith for publication as 

 North American Fauna Mo. 37 a revision of the American marmots, 

 by Arthur H. Howell, assistant biologist of the Biological Survey. 



Although marmots are found over most of the United States and 

 Canada, the relationships and ranges of the several species until now 

 have been very imperfectly known. The present report furnishes 

 descriptions of 26 forms and contains a series of maps shomng their 

 geographic distribution. In many localities marmots are a decided 

 pest to agriculture, especially in the East, both because they are 

 destructive to crops and because their burrows seriously interfere 

 with farming operations. Moreover, marmots are known to carry 

 the germs of Rocky Mountain spotted fever and other diseases. The 

 animals are hence of considerable economic importance. 

 Respectfully, 



Henry W. Henshaw, 

 ChieJ, Biological Survey. 



Hon. David F. Houston, 



Secretary of Agriculture. 



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