PREFACE TO BULLETIN. 



It is the purpose of this bulletin to include such miscellaneous 

 technical papers on insects, other than the scolytid beetles, as are 

 either injurious or beneficial and of more or less importance in their 

 relation to American forests. These papers are based largely, if 

 not entirely, on original observations and investigations, supple- 

 mented by material in the United States National Museum, and 

 serve as a necessary basis for the nontechnical papers on the same 

 insects. As they are intended to be of service especially to the 

 economic entomologist and to the student of forest entomology, 

 they are, as a rule, presented in a somewhat less formal style than 

 if intended for the systematist onl}'. 



A. D. H. 



