82 THE CHINCH BUG. 
In Ohio, which appears to be the frontier of destructive abundance, 
the line separating the habitat of the combined forms and that of the 
macropterous form, exclusively, indistinctly marks the line of separa- 
tion between the most serious depredations and almost total immunity 
of attack on timothy meadows by chinch bugs. To the west and 
south of this a short-winged adult chinch bug is rarely seen, timothy 
meadows are seldom attacked, and then only where fields of small 
grain or corn are not in easy reach; as, for illustration, where the in- 
sect happens to breed in a wheat field surrounded by timothy, and, 
when the grain is harvested, there is no other recourse left it but to- 
attack the grass. In the opposite direction from our line, however, 
the conditions are quite the reverse. Here, while fields of wheat are 
eccasionally badly injured, thousands of acres of timothy meadow 
have been entirely killed out from its attack. 
The area of destructive infestation of timothy meadows seems to 
extend on the east in Ohio from Lake Erie to the Ohio River at the 
northernmost point of West Virginia, and on the west, in the vicinity 
of Sandusky, it extends only 25 or 30 miles from the lake shore. In 
limited numbers the area of distribution extends westward, probably 
narrowing gradually, around the lower end of Lake Michigan into 
northern Illinois, where it seems to be on the increase, though still 
far from common. <As will be shown further on, this form is not 
likely to become destructive where timothy is grown in rotation with 
other farm crops. 
So far as it 1s possible to determine, there are a considerable number 
of winged adults produced in this area every year—perhaps from 30 
to 50 per cent some seasons—and these breed in the grain fields; but 
at wheat harvest, instead of migrating to the corn, as is done else- 
where, they go by preference to the timothy meadows. In western 
New York, where both the long and short winged forms occur, Mr. 
Van Duzee wrote that he had never found an individual of either 
form in grain fields, but that they both literally swarm in timothy 
during some years. Doctor Lintner told the writer that in the serious 
outbreak of this pest in the meadows of New York in 1882 and 1883 
about 20 per cent were of the short-winged form. Doctor Perkins has 
recorded an attack of the chinch bug in a timothy meadow in northern 
Vermont. Whether or not the short-winged form was the depredator 
in this last-named locality the writer is unable to say, but, generally 
speaking, the short-winged form is unknown at any considerable 
distance from the coast, except in Maine, New York, Ohio, Ontario, 
and northern Indiana, and but rarely does it occur in either form in 
the two latter localities. 
Just why this short-winged form should occur in such abundance in 
the three States named is a matter that the writer is at present unable 
fully to explain; but it does seem that this difference in food habits as 
