Technical Series, No. 1 /, Part I. 



U. S. DEPARTMENT OF AGRICULTURE, 



L. 0, HOWARD, Entomologist and Chief of Bureau. 



COXTRIBUTIOXS TOAYARD A MONOGRAPH OF 

 THE SCOLYTID BEETLES. 



L THE GENUS DEiNDROCTONUS. 



A. D. HOPKINS, Ph. D., 



In Charge of Fun: d Inaect Inrestlgations. 



Issued June 30, 1909. 



WASHINGTON 



GOVERNMENT PRINTING OFFICE. 



19 9. / <y 



>^ % 



DEC?. 9 1909. ' 



