PREFACE. 3 
Europe as many destructive species as in Europe. But we have many 
more shade and forest trees of importance in the eastern United States 
alone, and when we add to these the forest trees of the western Rocky 
Mountain plateau and of the Pacific coast, and when we look forward 
to the attention which must be given in the immediate future to the 
planting of shade and forest trees on the great plains and in California, 
the subject of forest entomology assumes still more importance. 
The author has here arranged the forest trees in the order of their 
importance, beginning with the hard-wood or deciduous trees, the oak 
heading the list, and ending with the coniferous trees ; and under each 
tree he has first described the habits of the insect on the whole most 
injurious, sometimes merely giving a list of those insects found to be 
regular parasites of the tree but not specially injurious, though it 
should be borne in mind that any species of insect may at certain sea- 
sons so abound as to prove destructive. 
In preparing the original bulletin, the author was, for valuable infor- 
mation regarding the food-trees of a number of beetles hitherto unpub- 
lished, indebted to Mr. George Hunt, of Providence, R. I., and for aid 
in collecting specimens he acknowledged the assistance received from 
Mr. Edwin C. Calder, formerly assistant instructor in chemistry, Brown 
University, and from Prof. H. C. Bumpus, then a member of the sopho- 
more class of Brown University. 
While preparing the work in its present form the author has been for 
the last four years connected with the Division of Entomology as a 
special agent, and matter contained in his reports have been incorpo- 
rated in this general work. And he takes pleasure in acknowledging 
the constant aid and sympathy in the work shown by Professor Riley r 
the United States Entomologist, not only in allowing free and unre- 
stricted use of specimens, both in his private collection and that which 
he has generously presented to the Agricultural Department at Wash- 
ington and to the National Museum, but for the privilege of describing 
the transformations of a number of species, represented by blown or, 
alcoholic larvae. Professor Riley has also freely made over to the author 
many hitherto unpublished notes of habits and transformations, which 
have been accumulating for the past twenty years — notes and observa- 
tions which most persons would naturally prefer to keep or publish in- 
dependently under their own names. These especially relate to oak and 
elm insects, besides others, and are acknowledged in the places where 
they appear. Be also contributes an account of the insects of the Celtis. 
Professor Riley has also allowed the use of some uupublished draw- 
ings and a few cuts prepared as Entomologist of the Department of 
Agriculture for future use. 
Thanks are also due to the late S. Lowell Elliott, esq., of Brooklyn, 
, Henry Edwards, esq., of New. York, and Professor Riley, as well as to 
Dr. G. H. Born, of Philadelphia; Dr. P. R. Uhler, of Baltimore; *Dr. 
J. A. Lintner, State entomologist of New York, Mr. L. O. Howard and 
