28 
longei, loss than half the width of the seventh, and truncate 
posteriorly.. Beneath, the seventh segment is the longest, and 
the eighth is very short, especially at middle. 
Adult. (Plate IV, Fig. 5.)—Length 5 to 6 mm. Body elon¬ 
gate-oval, smooth, moderately shining, black, evenly and' finely, 
but not densely, punctured. Wing-covers with four vellowish 
spots, one at the base and one near the tip of each. These 
vary in extent and color. The wing-covers are subtruncate at 
apex, exposing the tip of the abdomen above. 
WIRE WORMS. 
(Elaterid.e.) 
h ailure of the seed to start, or a sudden withering of the corn 
plant when a foot or two in height, especially if the field was 
broken up from grass one or two years preceding, are always 
sufficient to warrant a suspicion of injury by wireworms. These 
hard, smooth, shining, reddish or yellowish brown cylindrical 
six-legged larvae" are indeed much more destructive to seed-corn, 
under ground, in Illinois than all other insects taken together. 
They may begin their injuries to the seed almost immediately 
after planting, commonly burying their heads in it at first, 
sometimes eating entirely through the kernel, and even devour¬ 
ing it completely. If they attack the- growing plant they are 
likely to eat the smaller roots, or to penetrate or bore through 
the larger ones, dwarfing or killing’ the corn; and later, when 
the young plant is several inches high, they frequently kill it 
outright by boring their cylindrical channels directly through 
the underground part of the stalk. They are far the common¬ 
est in corn on ground which has lain for several years in grass, 
and are much more likely to do serious mischief the second 
year after the breaking up of the sod. They should be sought 
for diligently on such lands whenever the seed fails to grow, 
or when the sudden withering of the plant hints at a serious 
damage to it under ground. At such times practically all the 
wireworms in the field will be found in the hills of corn or in 
their immediate vicinity, sometimes as many as ten or a dozen 
in each hill. 
Although wireworms are rarely distinguished by farmers as of 
different kinds, there are no less than one hundred species of 
these insects knowm to occur in Illinois in the adult, or beetle, 
stage, and eight species of the larvae (the so-called “wireworms” 
themselves) 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 
b} r the fairly good observer who has once learned to recognize 
any one of them. They vary in length, wffien full grown, from 
half an inch to an inch and a quarter, but agree in their hard, 
general ( l escr JPfi on wireworms does not apply to one very peculiar form 
(.Cardiophorus) taken but once in Illinois, and described on page 32. 
