20 
THE CHINCH BUG. 
moutli later in development than others, in two localities not far distant 
(140 miles) and of about the same latitude. There are many accounts 
in print which are almost incredible tales of the size of these migrating 
hordes, and yet they are probably only too true. 
Dr. Thomas states that the migration upon foot seldom exceeds 80 
rods, but the winged individuals fly to much greater distances. In- 
stance was given in the Farmers’ Beview for August 17, 1887, where a 
little patch of sweet corn grown in the midst of pine woods in northern 
Wisconsin, 8 miles from a cultivated crop of any kind, was badly in- 
fested with the Chinch Bug. This appearance of the bugs probably re- 
sulted from the flight thereto of mature individuals. 
It naturally results from the wide difference in the method of growth 
of the crops that the Chinch Bugs after migrating from wheat to corn 
appear to be much more numerous upon the latter crop than they were 
upon the former, in spite of the great numbers usually killed in the act 
of migrating; for a single stalk of corn will be obliged to support the 
Chinch Bugs from a great many stalks of wheat. Moreover, the bugs 
swarm upon the lirst few rows and destroy them before invading the 
entire field generally. The outer rows, of course, under these circum- 
stances are often black with bugs. The pupae work their way down 
between the leaves and the stalks and there cast their skins and issue 
as adult insects. The leaf sheath is often thus completely filled with 
exuviae. The eggs for the second brood are also often if not usually 
deposited in this same situation — behind the sheaths of the lower 
leaves — and on hatching the young bugs remain there feeding and 
growing, and casting skins, sometimes even until the advent of cold 
weather and their consequent winter torpor. Others issue from these 
sheaths, particularly when they are especially abundant, or failing to 
find satisfactory locations on the outer rows take wings and fly to the 
center of the field and become generally scattered. They feed upon the 
Corn or Bye as the case may be, and upon the surrounding grasses or in 
the fields of Millet or Hungarian grass until the approach of fall, by 
which time nearly all are once more full-grown. Mr. Webster observed 
them at Lafayette, Ind., in August, 1887, forcing themselves down into cut 
stubble of Setaria glauca for the purpose of undergoing the last molt. 
He counted upwards of twenty in a single stalk. We may mention in 
this connection, as reported to us by Prof. Osborn and also as published 
in the Country Gentleman for August 25, 1877, that President Cham- 
berlain, of the Iowa Agricultural College, dug a single root of Hungarian 
grass at Ames, Iowa, the first week in August upon which were counted 
3,025 bugs. Earth was removed with the root to the depth of 3 inches 
(1 inch surface), in all about 4 cubic inches. 
In the north the majority of them are ready to hibernate by the time 
the field corn is harvested. Farther south, however, the corn grows 
too hard for them and considerable time before the weather is cold 
enough to compel them to seek winter shelter. In North Carolina, as 
