5 
have received tke largest share of our attention. During both sum- 
mers periodical sowings of wheat were made in southern Illinois on 
selected plots, from harvest to the usual seeding time in fall, to de- 
termine more precisely the summer history of the fly. Those of 
— 1887 failed because of the extreme drouth, but those of 1888 con- 
firmed the results of similar experiments made by us in 1886. Office 
experiments with this insect are now in progress. 
The corn plant louse we have studied by careful field observation 
and by continuous breeding experiments in the laboratory, made es- 
pecially during fall and spring. These experiments have determined 
the spring and winter history of the root louse; and others made. by 
enclosing hills of corn in the field with large gauze-covered frames 
have thrown much light on the midsummer history and breeding 
habits of this species. We are now carrying this insect through the 
winter in the botanical conservatory under conditions to give us ad- 
ditional information concerning it. Colonies of the small brown 
ant to whose ministrations these plant lice are especially indebted, 
have been artificially reared and regularly observed through the 
season to determine their life history and habits. 
Several species of our cutworms have been bred by us for the 
first time,—one, phenomenally destructive this year throughout the 
whole State, never before identified nor noticed. 
| We have made, both years, studies of the web worms injuring 
-eorn and grass lands, with experiments for their destruction. 
In the spring and early summer of 1888 we made many elabo- 
rate experiments with insecticides for the destruction of wireworms 
in corn. 
| In 1887 the life history and habits of an insect destructive to 
meadows,—the larva of one of the crane flies not before known as 
injurious,—was ascertained by field and laboratory observations; 
studies were made of some of the insects most injurious to nursery 
stock; additional experiments were conducted for the control of in- 
juries fo fruits by the codling moth; the life history, species, and 
habits of a new plum borer were determined; considerable systematic 
and biological work was done on a large number of plant louse 
species, and an elaborate research was carried forward on the conta- 
gious diseases of the army worm, several species of cutworms, and 
the cabbage caterpillar. 
In 1888 we also learned the habits, developmert, and history of 
a large snout beetle responsible for a frequent and extensive injury 
Wea ee 2 
