SPRING, SUMMER, AND AUTUMN MIGRATIONS. 19 
commonly appear on the back furrows or on any slight elevations 
that occur in the field. But on higher and level ground the whitening 
areas are observed scattered over the entire field, and constantly 
widening until the whole field appears to ripen prematurely and 
crinkle down. When the migration is accomplished by crawling, 
the females seem to spread only enough to afford food for the young 
until the latter are able to make their own way from place to place. 
The young remain clustered on the plant about which they were 
hatched until this has been drained of sap, when they make their way, 
almost in a body, to a second plant, and in this way an attack will be 
pushed forward day after day. 
In the spring the chinch bug probably lingers about its winter quar- 
ters until a favorable day for migration occurs. ‘Transfer a typical 
Indian summer day to early May, and perhaps raise the tempera- 
ture a few degrees, and you have a day during which chinch bugs 
may be seen on the wing, crawling along on fences, or at rest on the 
tops of fence posts as if taking observations, and in reality, as the 
writer has come to believe, to catch the scent of wheat or corn fields. 
It is on just such a day as this that Aphodius serval Say will be 
observed posted in precisely the same way, opening and closing the 
leaves of its antenne, evidently to catch the scent of the fresh drop- 
pings of animals. The same movements characterize Aphodius inqui- 
natus HUbst. during the Indian summer days of autumn. The writer 
has also observed the plum curculio, Conotrachelus nenuphar Ubst., 
acting in precisely the same way in late autumn. 
While discussing the subject of chinch-bug migrations, it may be 
best to state here that there is a second flight of chinch bugs in sum- 
mer after the majority have become fully developed, and not as soon 
as the individual reaches the adult stage, as Professor Saj6 has found 
to be the case with the European species, Blissus doriw Ferr. A 
migration by flight takes place in the fall, usually during the period 
of Indian summer. The magnitude of such migrations depends in 
the spring on the number of individuals that have been in hiberna- 
tion, and in the summer and fall entirely on the abundance of the 
species during the current year. If there has been no great abun- 
dance during the spring the summer flight will not be lkely to attract 
attention. During .the ‘invasion of 1896 in Ohio an individual 
alighted on the writer’s hand while he was riding on a street car in 
the heart of the city of Columbus. A heavy storm of rain has much 
influence in scattering the bugs in midsummer, and just preceding a 
heavy rain the writer has noted the fully developed adults very 
abundant on Indian corn plants, while immediately after the storm 
there would be very few to be found. As these storms were not 
always accompanied by high winds, it is probable that it is the rain- 
fall that scatters the insects. 
