q INTRODUCTORY. 
J For the past ten years the economic entomology of the corn plant 
has been made a leading subject of investigation in this State by the 
official entomologist, and in the course of these original studies a large 
mass of published matter has been scanned and summarized. The 
; _ present report has been prepared in the hope (1) of finally bringing to 
bear on the practice of the corn farmer in Illinois all the entomological 
matter that ought to affect his procedure, and (2) of so massing “and 
_ condensing the data from which practical and theoretical conclusions 
are to be drawn as to make it unnecessary for the investigating ento- 
-mologist to cover the same ground again. 
} To the first end I have prepared descriptions and classifications of 
insect injuries to corn which I venture to hope will be found intelligible 
and practically useful to the actual tiller of the soil as well as to the 
- economic entomologist ; and secondly, I have incorporated with this, for 
_ the especial benefit of the entomologist, more detailed and thoroughgoing 
discussions of the insects themselves and of their life histories, habits, 
and injuries, together with descriptions of the species in all stages as yet 
recognized. This report is thus written from both the agricultural and 
the entomological standpoints. 
_ he corn insects now recognized as in some way and to some extent 
injurious to some part of the plant number 214 species, of which 18 are 
known to infest the seed, 27 the root and the subterranean part of the 
stalk, 76 the stalk above ground, 118 the leaf, 19 the blossom,—that 
is the tassel and the silk,—42 the ear in the field, 2 the stacked fodder, 
and 24 the corn in store, either whole or ground. The greater part of 
this long list, which is doubtless by no means really complete, is com- 
_ posed of those whose injuries are now so shght or rare as to constitute 
S a- possible menace rather than to cause a serious loss; but the history of 
economic entomology, and even of the entomology of this one plant, 
_ teaches us that we can rarely tell in advance what to expect of any pos- 
_ sibly injurious species. In fact, some of the insect enemies of corn now 
. most destructive were not many years ago almost unknown even to the 
~ entomologist—the northern corn root worm and the corn root aphis, for 
‘ _ example. 
The principal insect species infesting this plant are the seed-corn 
maggot and the wireworms, attacking the “seed: these latter insects, the 
white grubs, the corn root worms, and the root aphis, affecting the roots ; 
_ the cutworms and root web-worms, the army worm, the stalk-borer. the 
corn worm, the bill bugs, the chinch bug, the corn flea-beetle, and the 
orasshoppers, injuring stalk and leaf; the corn worm, the corn root 
worms, and the grasshoppers, eating the flower structures and the ear; 
and the meal-moth and the weevils devouring the kernel in the granary 
‘i or the meal in the bin. Of these, by far the worst at present are the 
_wireworms, the corn root worms, the white grubs, the root lice, the cut- 
“worms, the chinch bug, the orasshoppers, and the army worm, 
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