PREFACE TO BULLETIN. 
During the writer's investigations of extensive insect depredations 
in the forests of West Virginia, from 1890 to 1902, he was forcibly 
impressed with the importance of the forest-insect problem in con- 
nection with any future efforts toward the successful management of 
the forests of this country, and was thus led to give special atten- 
tion to the subject. It was soon realized that among the principal 
groups of insect enemies of forest trees the scolytid bark and wood 
boring beetles must occupy first rank, both in economic importance 
and systematic interest. Subsequent investigations in West Vir- 
ginia, in connection with the work of the West Virginia Agricultural 
Experiment Station, and in all of the principal forest regions of the 
country, in connection with the work of the Bureau of Entomology, 
have served to confirm these first impressions. 
In these investigations special efforts have been made to acquire 
information on the habits and seasonal history and other facts relat- 
ing to the various species, and to collect an abundance of material 
for systematic study, all to form a basis for conclusions in regard to 
the principal enemies of American forests and practical methods for 
their control. 
The results of these investigations will be published in the two 
series of bulletins issued by the Bureau of Entomology. Those relat- 
ing to the purely technical or systematic side of the subject, and of 
more direct interest to the systematic and economic entomologist 
and the general student of entomology, will be published in the 
technical series, while those of special interest to the economic ento- 
mologist, the student of forest entomology, the technical and practi- 
cal forester, the owner of private forests, the manufacturer of forest 
products, and the public generally will be included in the regular, 
economic series of bulletins. The bulletins of each series are to be 
issued in parts, each part relating to a special group or genus as the 
work thereon is completed, thus avoiding the otherwise necessary 
delay in publication. A full index will be published to accompany 
each completed bulletin of several hundred pages. 
A. D. H. 
