U. S. DEPARTMENT OF AGRICULTURE, 

 BUREAD OF ENTOMOLOGY— BULLETIN No. 83, Part L 



L. O. HOWARD, EntomologUi and Chief of Bureau. 



PRACTICAL INFORMATION ON THE SCOLYTID BEETLES 

 OF NORTH AMERICAN FORESTS. 



I. BAUKBEETLES OF THE GENUS 

 DENDROCTONUS. 



A. D. HOPKINS, Ph. D., 



In Charge of Forest Insect Investigaticeas. 



WASHINGTON: 



GOVERNMENT PRINTING OFFICE. 

 1909. 



