113 
In addition to affording an excellent illustration of the de¬ 
structive capacity of the common white grubs, this record is of 
special interest as evidence that L. rugosa at least will lay its 
eggs and breed abundantly in fields of corn. On no other sup¬ 
position can we explain the appearance of such vast numbers of 
partly grown larvse three years after the ground was broken from 
grass in the spring; three years, that is, subsequent to the latest 
time at which the eggs could possibly have been laid in the grass. 
It seems very likely that this second lot of grubs was hatched 
from eggs laid in the corn in the summer of 1890 by the beetles 
which came out of the ground in this same field. If this infer¬ 
ence be correct, it follows that planting to hemp for a year will 
not clear the ground of grubs. 
A somewhat similar inference of a readiness to breed in corn 
is to be drawn from our observations on another plot of about 
four acres on the Universitv farm near Urbana. This field, 
broken up in the spring of 1890 and put into corn, was planted 
in 1891 partly to corn, and partly to oats; in 1892 to oats and 
corn again, but with the areas reversed; and in 1893 to corn. 
On this the third year from sod, more than half the corn fell 
flat on the ground by the middle of September, most of the 
roots being eaten off by white grubs, of which three or four 
were commonly to be found in a hill. Owing to the consequent 
weakening of the plant the brace roots failed to form, the ears 
which set were small and very often imperfect, and a large per¬ 
centage of the stalks were barren, the total height of the plant 
varying from six or eight feet to less than a foot. Even the 
tallest stalks were slender and unhealthy in appearance, the 
lower leaves, and sometimes practically the entire foliage of the 
plant, being as dry and brittle as in midwinter. Those stalks 
which had been killed early were usually so decayed as to be 
readily pulled apart at the nodes. 
From these data we must conclude that the species concerned— 
which was either inverse or iusca —may live as a larva through 
four full years, making the entire life history cover a five-year 
period, or else that the eggs were laid later than 1889 in either 
corn or oats. 
The w T hite grubs taken by us in corn fields under circumstances 
to satisfy us that they either were or had been feeding on the 
roots of corn belong to eight species, as follows: Lacknosterna, 
fusca , tristis, inversa, hirticvla . rugosa, gibbosa, and ilicis, and 
Cyclocephala immaculata. Of these L. fusca , in versa, and rugosa 
are much the most common in such situations; and to them by 
far the greater part of the damage done to corn by the white 
grubs in central Illinois must be attributed. 
Next to Indian corn, the crop most generally and seriously in¬ 
jured in Illinois by grubs is grass; and here the loss is the more 
serious because continuous and usually unnoticed. A very large 
number of these insects may live their long lives in the sod, 
