42 
amount and dwarfed in size, a. difference appaient, I 'was told, 
from the beginning of the spring, and which doubtless originat¬ 
ed the fall preceding. These areas were said to be enlarging, 
beiim- at the above date about four times as large as they were 
March 1. The corn stubble remaining in the field among the 
wheat was very much smaller on these spots than on ground 
adjacent, showing that the preceding crop had been injured, and 
the owner reported, indeed, that the yield was very greatly di¬ 
minished there the year before. In the earth of these bare 
patches full-grown white grubs occurred at the rate of about 
five or six to the square foot; while in the uninjured wheat near 
by they averaged one to every two square feet. 
Beginning in 1884, this ground had been in corn foi thiee 
successive years. It was planted to oats in 1887, to coin m 
1888. and to wheat the autumn of that same year. Without 
a knowledge of the length of the life cycle of our white grubs— 
a thino’ on which we have now no precise information we can¬ 
not, say in which of the crops just mentioned the mother 
beetles of these grubs laid their eggs. It was clearly, however, 
in cultivated ground. 
Mr. Martin Plank's Field .—In this field of twenty acres a re¬ 
markable injurv to corn occurred in 18(89 and 1890,. during 
the first and second years after grass, the ground having lam 
in pasture since 1884. By the time this year the young corn 
was six inches high a large part of it had been destroyed by 
the grubs, and a space of two or three acres Avas harrowed 
over and sowed to hemp. During the preceding year, 188 J \ e 
similar but inferior damage was noticed at the time ol tnc 
grain harvest, much of the corn blowing down easily from f 
Toss of the roots. At this time there were from six to a dozei 
white grubs in an injured hill, and the corn on about four oi 
five acres of the highest land was a total failuie, t le oA\ei 
ground yielding a light crop. The grubs in this field when th< 
ground was plowed in the spring of 1890, were so numeroui 
that a careful estimate, based on a count of those found withii 
a space a rod long in a fourteen-inch furrow, gave between sn 
and seven hundred to the square rod, or nearly three hundrei 
pounds per acre. Numerous breeding experiments with materia 
from this field, showed that the most abundant species was L 
rugosa. A few examples of inversa Avere, hoAvever, dug up late 
in the same field. 
Food oflmagos— The adult beetles have apparently a varij 
ous habit of food, the different species exhibiting special preiei 
ences; but beyond this general statement it is impossible a 
present to give very definite particulars. Among the tree 
whose lea\ T es they eat are oak, ash, maple, box eldei, birc j 
elm, chestnut, mountain ash, plum, and cherry It is not con 
monly known, I think, that they will feed freely, if compellec 
upon the blades of blue grass. We have also found them one 
feeding on clover heads and on the leaves of corn. 
