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assistant $100 for the present year only. The salaries of the 
office entomologist, field entomologist, and amanuensis (who 
acts also as librarian) have been, respectively, $600, $900, and 
$600. 
Owing to changes of assistants, indirectly due to the or- 
ganization of a large number of new state agricultural experi- — 
ment stations, the general zodlogical work of the State Natural 
History Survey has materially fallen off, but relatively greater 
attention has been given to economic investigation. The 
zodlogical work has been limited to considerable additions to 
the ornithological collections, made for a further study of the 
food of birds; and desultory studies on the lower aquatic ani- 
mals of the state, especially insect larvae, Vermes, and Protozoa. 
The progress of our knowledge of the aquatic zodlogy of Ilh- 
nois has been indirectly advanced by vacation work done out- 
side our state limits,— during the summer of 1889 in northern 
Michigan and Lake Superior, and during that of 1890 in the 
lakes and streams of the northern Rocky Mountains. Reports — 
on these collections have been prepared, or are in course of — 
preparation, for publication by the U.S. Fish Commissioner, 
and as this material is studied, our similar and parallel collec- 
tions from this state are studied with it, to the great advantage ~ 
of the local work. 
Our entomological investigations have been, as heretofore, 
almost wholly economic in their motive; nevertheless, no oppor- — 
tunity has been lost to improve our acquaintance with the in- — 
sects of Illinois, whether economically interesting or not. The 
building of an insectary and separate office (the former devoted 
to experimental work upon the life histories of insects, their 
injuries to vegetation, and methods of practically controlling 
them) has given us an opportunity not before enjoyed for con-— 
tinuous observation and accurate experiment on some of the 
most difficult species. The principal subjects which we have 
studied are the life histories of cutworms, the contagious dis- 
eases of the chinch bug, the life history of the corn root louse 
and of the species of ant uniformly associated with it, the 
feeding habits of the plum and peach curculio with insecticide | 
experiments for its destruction on the peach, the stages and 
life history of a new plum borer, the injuries to fruit by the 
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