11 
assistant has also often rendered valuable incidental service, and 
the librarian of the Laboratory has spent much time in indexing and 
arranging entomological literature, and in making the index to the 
preceding reports of the office already mentioned. 
I have further used a part of the small appropriation made by 
the last legislature for the office and traveling expenses of the State 
Entomologist, in payment for clerical assistance on the correspond- 
ence of the office, and on the preparation and publication of my 
report. 
FIELD OPERATIONS. 
One hundred and fourteen days of the past season have been 
spent by myself or my assistants in entomological field work, out- 
side of this county. Our collections and observations have been 
made in thirty-one different counties of the State, from Cook and 
Ogle on the north to Alexander and Gallatin on the south, and 
from Madison, Hancock and Rock Island on the west to Cham- 
paign and Grundy on the east, the railroad and steamboat travel 
performed on these trips amounting to very nearly six thousand 
miles. In the intervals of these longer journeys, field work has 
been in constant progress in the vicinity of the Laboratory. 
SPECIAL INVESTIGATIONS. 
The subjects which, above all others, have claimed our attention 
this summer, are the wheat bulb-worm, the Hessian fly, the straw- 
berry root-worms, the tarnished plant-bug, the corn plant-louse 
and other insects attacking corn in the ground, the plant-lice 
affecting sorghum and broom-corn, and the contagious diseases of 
the Kuropean cabbage worm and other injurious insects. 
The life-history and habits of the wheat bulb-worm, the tarnished 
plant-bug and the strawberry root-worms have been nearly or quite 
made out, and full reports on these insects are herewith presented. 
Satisfactory progress has been made on the other subjects men- 
tioned above, as also on a variety of studies of inferior economic 
importance; but a report of these investigations is withheld at 
present, chiefly from reluctance to publish on unfinished subjects. 
CHARACTER OF THE REPORT. 
From the material available for this report, I have selected such 
articles as were complete and of especial economic value at this 
time, and have given an elaborate account of all insects known to 
be injurious to the strawberry. I have selected this fruit for 
especial treatment this year, because of the rapidly growing import- 
ance of strawberry culture in this State; because it seems to have 
received less than its share of attention in the former reports from 
this office; and because more has been lately discovered relating to 
its insect enemies than to those of any other crop. 
It is my ambition and purpose to make my reports, as a general 
rule, an exhibit of our own original work, and not a compilation of 
work done by others; but the advantage of occasionally treating the 
subject of all insect injuries to a single crop as a whole, adding to 
