30 
be possible to poison it by the usual insecticides, especially Paris 
Green and London Purple, but this practice will doubtless be far 
more expensive than the method of rotation, and would be highly 
dangerous to stock. Clean cultivation in and outside the field, 
which has been previously recommended, would have but little, if 
any effect, since the beetle finds an abundance of food from the 
corn itself, and even in molds and decaying vegetable tissues, 
if deprived of all other sources of support. Finally, too much 
emphasis cannot be placed on the fact that an intelligent rotation 
of crops constitutes our only present safeguard against what now 
threatens to become a most destructive scourge unless met in this 
way. 
SUMMARY. 
The corn root-worm, in the form in which it affects the roots of 
corn, is a slender white grub, not thicker than a pin, from one- 
fourth to three-eighths of an inch in length, with a small brown 
head, and six very short legs. It commences its attack on the root 
in May or June, eating its way beneath the surface, and killing 
the root as fast as it proceeds. Late in July or early in August 
it transforms in the ground, near the base of the hill, changing 
into a white pupa, about .15 of an inch long and _ two-thirds 
that width, looking somewhat like an adult beetle, but with the 
wings and wing-covers rudimentary, and with the legs closely 
drawn up against the body. A few days later it emerges as a 
perfect insect, about one-fifth of an inch in length, varying in 
color from pale greenish-brown to bright grass-green, and usually 
without spots or markings of any kind. The beetle climbs up 
the stalk, living on fallen pollen and upon the silk at the top of 
the ear until the latter dries, when a few of the beetles creep 
down between the husks, and feed upun the corn itself, while the 
others resort for food to the pollen of such weeds in the field as 
are at that time in blossom. In September and October, the eggs 
are laid in the ground, upon or about the roots of the corn, and 
most of the beetles soon after disappear from the field. They. 
may ordinarily be found upon the late blooming plants, feeding as 
usual upon the pollen of the flowers, and also to some extent upon 
molds and other fungi, and upon decaying vegetation. The insect 
hibernates in the egg, as a rule, and this does not hatch until after 
the ground has been plowed and planted to corn in the spring, 
probably in May and June. It occurs in destructive numbers 
throughout Illinois, from DeKalb to Morgan counties, and as far 
west as Iowa, and also less abundantly in Southern Illinois. It is 
at present most abundant and injurious north, where the chinch- 
bug has compelled a partial suspension of the culture of wheat. 
Although the adult beetles, when numerous, do some harm by 
eating the silk before the kernels aré fertilized by the pollen, and 
also destroy occasionally a few kernels in the tip of the ear, yet the 
principal injury is done by the larva in its attack upon the roots. 
The extent of this injury depends not only upon the number of the 
worms, but also upon the soil and weather and the general condi- 
tion of the crop, being worst on high land and in dry weather. 
