186 REPOET OF THE COMMISSIONEE OF AGRICULTURE. 



Much information has been gained respecting insects injurious to 

 orange trees. Accounts of a few of these insects are inchided in the 

 following report. But I am able to i:)resent at this time only a small 

 part of the data which I have collected on this subject, owing to lack of 

 time for preparing the remainder for the press. 



Accounts of many other insects which have been studied during the 

 year are not included in tliis report, as in many instances it is desirable 

 that further observations be made before publishing the results obtained. 



Believing that the work of this Division should be of a practical na- 

 ture, I have, in ihy investigations, confined myself as far as possible to 

 the study of tbe habits of insects and to experiments with remedies. 

 However, for the sake of scientific accuracy, it is necessary that the ex- 

 act zoological position of the species described should be indicated, and f 

 that the new species should be characterized in a technical manner. 

 This is a work which can be well done only by one who devotes his ex- 

 clusive attention to the systematic study of the particular group of in- 

 sects to which the species in question belongs. I have therefore invited 

 the aid of specialists in work of this nature ; and in every case the as- 

 sistance has been promptly and cheerfully rendered, and without pecu- 

 niary recompense. 



In this connection I wish to aclcnowledge the aid of the following- 

 named gentlemen : Mr. Edward Burgess, for determinations and descrip- 

 tions of Diptera -, Mr. V. T. Chambers, for determinations and descrij)- 

 tions of Tineids ; Mr. E. T. Cresson, for determinations and descriptions 

 of Ichneumon flies ; Prof. C. H. Fernald, for determinations and descrip- 

 tions of Tortricids ; Mr. A. E. Grote, for determinations of Noctuids ; Dr. 

 George Horn and Mr. Henry Ulke, for determinations of Coleoptera ; Mr. 

 L. O. Howard, for description of a Chalcid; Mr. J. Monell, for description 

 of an Aphid ; Mr. Edward Norton, for description of a Saw-fly, and Dr. 

 P. E. IJhler for determinations and descriptions of Hemiptera. 



The correspondence of the Division has continued to increase during 

 the past year. Very many inquiries respecting noxious insects and the 

 means of preventing theii* ravages have been received from all parts of 

 the country. This correspondence has occupied much of my own time 

 and all that of an assistant. A large part of these inquiries were re- 

 specting well-known insects, and I trust that in many instances informa- 

 tion has been given which has materially aided our correspondents in 

 combating the pests. In other cases the insects have proven to be new 

 to science, or species whose habits were unknown. In this way many 

 interesting and important subjects for study have been presented. 



Large additions have been made to the biological collection of the 

 Division, among which may be mentioned over 1,600 slides of microscop- 

 ical insects and about 40 cases of larger specimens. 



I take pleasure in acknowledging the assistance of Mr. L. O. Howard 

 in the preparation of this report, and in the general work of the Di- 

 vision ; also the aid of Mr. Th. Pergande in the care of the insects bred 

 in my office, and in making biological notes upon them. The original 

 figures illustrating this report have been drawn from nature by Mr. 

 George Marx. 



Eespectfully submitted June 30, 1880. 



J. HENEY COMSTOCK, 



JUntomoIogist 



Hon. William G. Le Duo, 



Commissioner of Agriculture. 



