8 
fiom townships in Central and Northern Illinois in which not am 
acre of wheat was reported, to others—mostly in the southern 
part of the State—where the wheat area ranged from 10,000 to 
13,000 acres per township.* 
Further, where damage had been done, it was in some cases 
barely perceptible for the first time in many years, and in others had 
been repeated with extreme severity for several successive seasons. 
This made easily possible elaborate comparison in all parts of the 
State between the wheat acreage and the amount of chinch-bug 
damage done to the principal crops. If the latter was found to 
vary generally with the former, the area in wheat increasing or 
diminishing where injury to corn, grass, etc., was greater or less, 
the presumption would be very strong that there was some con¬ 
nection of cause and effect between these two sets of data. I con¬ 
sequently undertook to collect, classify, and discuss the facts 
obtainable in this State bearing on this important matter,—a labor 
which has absorbed much of my own time and the greater part 
of that of two assistants during some months of the summer and 
fall. The scope of my inquiry was finally widened so as to in¬ 
clude an examination of the relations of chinch-bug injury to corn 
and grass, as well as to wheat and the other small grains, with a 
view to showing the kind of rotation or cropping prevalent in the 
worst infested districts as compared with those nearly or quite 
free from damage. 
COLLECTION OF DATA. 
For the facts of both orders, I had recourse to township as¬ 
sessors throughout the State. Those concerning acreage in wheat 
and other crops were compiled from the Assessors’ Reports for 
the years 1886 and 1887 on file at the Stat.? Capitol; and those 
concerning insect injury to small grain, corn, and grass, were 
secured by correspondence with the officers who made the assess¬ 
ment for 1887. In order that the last mentioned facts might be 
uniformly stated in a way to make them available for tabulation, 
the following slip and postal-card circular were sent to every as¬ 
sessor in the State. The terms selected for the card of inquiry 
made a series as uniformly graded as was convenient, of expres¬ 
sions to which every one was accustomed and to which all would 
attach a practically identical meaning. 
Office State Entomologist, 
Champaign, III., March 5, 1888. 
Dear Sir: As an important item in an investigation of the relations of wheat culture to 
the chinch bug, which I have undertaken, I need an estimate, by assessors, of the amount of chinch- 
bug injury in their respective towns for the season of 1887. Will you be kind enough to note upon 
the card enclosed yourjudgment of this matter, returning to me without unnecessary delay? 
Very Respectfully, 
S. A. FORBES, 
State Entomologist. 
•This last in Washington county. 
