As this is a surmise or inference, however, and not a matter 
of observation, it remains possible that if the corn root worm 
is neglected it may in time accumulate in such numbers as no 
longer to confine its chief injuries to fields previously in corn, 
but that the beetles, forced to scatter early, in search of food, 
from the fields in which they emerge will deposit their eggs freely 
everywhere in the ground, instead of being* confined as now 
chiefly to corn fields. It is probably in fields of clover that this 
is most likely to occur, since the beetles sometimes become 
abundant there, feeding upon the pollen of the second growth. 
The depth at which the eggs are laid varies from an inch to 
five or six inches, the greater part of them being near the sur¬ 
face of the ground. They are usually deposited in bunches of 
three or four to eight or ten, within a space of half an inch 
across, not in contact with each other, nor in any cell or cavity, 
but always simply scattered in the earth. Most careful exami¬ 
nations made in 1882, and many times repeated, of the earth 
between the rows, and of the roots of all the weeds growing in 
the field, have failed to discover so much as a single egg out¬ 
side a space a few inches across, around each hill. A similar 
careful search of the roots of thistles, ragweeds, and goldenrod 
outside the fields, upon the flowers of which the beetles were 
feeding in great numbers, had a similar result; and we have 
found no evidence in the roots of these plants, either in the 
corn fields or elsewhere, that they have ever been infested by 
the larvae. In short, not the slightest direct proof has thus far 
been found that the beetle breeds anywhere except in fields of 
corn. It is very probable that a few develop in other situations; 
but the number seems to be so small as to defv discoverv, ex- 
cept by accident. 
NATURAL ENEMIES. 
Of natural enemies of this insect, practically nothing is known. 
While in the corn root, the larva is scarcely liable to harm. 
When outside the roots, it has possibly been destroyed now 
and then by predaceous insects, which are often numerous in 
and about, hills of corn, but dissections of insects of this class 
(reported in my Twelfth Report), do not confirm this supposi¬ 
tion. The soft-bodied pupae scattered in the earth without spe¬ 
cial protection of any kind would certainly seem to be exposed 
to insect enemies of this class, but of this fact we have no defi¬ 
nite evidence. The beetles are not eaten by birds, so far as 
known, and our breeding* experiments have yielded no insect 
parasites.* The spent adult, female or male, may become in- 
; fested before death with intestinal parasites (Gregarimc), and 
■we have occasionally found the dead bodies yielding a growth 
of Sporotrichum globuliferum —a fungus parasite of living* insects 
generally distributed everywhere. 
* An assistant, Mr. C. W. Woodworth, reported September, 1885, the finding of two small 
locustids—specimens of which wore not brought in—eating the adult Diabrotica. One of 
these was taken with a half eaten beetle in its jaws. 
-11 E. 
