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of corn or in their immediate vicinity, sometimes as many as ten or a 
a dozen in each hill. 
Although wireworms are rarely distinguished by farmers as of 
different kinds, there are no less than one sree species of these 
insects known ‘to occur in Illinois in the adult, or beetle, stage, and 
eight species of the larve (the so-called CninewOeins? themsely es) have 
been found by us here injurious to corn. ‘These corn wireworms have, 
however, so strong a family resemblance that they are little likely to be 
confused with « any other insect by the fairly good observer who has once 
learned to recognize any one of them. They vary in length, when full 
grown, from half an inch to an inch and a quarter, but agree in their 
hard, crust-like surface, nearly destitute of hairs; their brownie color, 
varying from yellowi ish to reddish; their slender bodies, distinctly seg- 
mented, and of about equal diameter throughout their length; their 
flattened heads, with jaws borne in front and extending horizontally 
forward ; the six pairs of short, stout, jointed legs on the three segments 
; following the head; the absence of legs of any kind on the eight seg- 
ments there after ; and the single sucker-like proleg on the under surface 
of the last segment of the body—the thirteenth, counting the head as 
one. ‘This terminal segment is often peculiarly finished above—concave 
or convex, notched, toothed or lobed at the sides and end, or, in one 
species, with a pair of conspicuous round openings on the upper surface. 
Taken in the fingers, the wireworms bend and wrigele with surprising 
strength, and easily slip out of the grasp. 
They live regularly and normally in grass lands, feeding on roots 
of grass, where, however, their numbers are rarely sufficient to produce 
any notable effect upon ‘the sod. It is only when concentrated in the 
comparatively scanty vegetation of a field of young corn in spring, or 
occasionally in young wheat or other small grain, that they do any very 
marked or important harm. They are to ‘he found in grass of every 
description, from prairie sod and the coarse and rank sedges along the 
borders of marshes, to the cultivated grass of our pastures and meadows. 
The commonest form of attack on the corn, as seen by the farmer, 
is, perhaps, the burrowing of the worm into the seed kernel, either before 
or after it has sprouted. All the species treated in this paper have been 
seen. with their heads buried in the kernels, either in the field or in 
breeding cages. Frequently attacks in the field have been so severe, par- 
ticularly the first or second year after the sod has been broken, as to 
require planting a second or third time. Drasterius elegans and Melano- 
tus fissilis have been taken in the act of perforating stalks just above 
the root. In a field at Peru, Illinois, examined in July, 1883, as much as 
six per cent. of the corn in the field had been killed in this way, some- 
times two or three larve being found in a single stem. 
The roots of the corn are also eaten to a greater or less extent by 
all the species, the damage from this cause being sometimes quite con- 
siderable. A field in Alexander county visited in June, 1886, had spots 
of one hundred to two hundred hills not more than a foot high, while 
the balance of the field was four or five feet high. Many hills in these 
spots were gone. In the smaller hills many, small, slender, peculiar- 
looking larve of an unknown species of Cardiophorus were found. In 
