BIENNIAL REPORT 
OF THE 
ILLINOIS STATE LABORATORY 
NATURAL HISTORY 
% the Trustees of the University of Illinois. . 
ire The operations of the State "Laboratory of Natural History 
u ing the past two years have been carried successfully forward along the 
ustomary lines of investigation, with a notable expansion, under the stimulus 
£ appropriations made by the last legislature, in the study of the contagious 
oo of insects and in the work of the Illinois River Biological Experiment 
tation. 
he insect-disease work took during the summer of 1895 the direction of an 
iestigation of the causes of our general failure in field experiments with 
re muscardine of the chinch-bug, together with an investigation of a newly 
iscovered disease of the common squash-bug. Among additional subjects 
udied, was a destructive disease of grasshoppers in the West, material for 
hich was obtained from a correspondent in Colorado, and the so-called white 
- of the common cabbage worm. 
The general result of our studies of the white muscardine has been to dis- 
edit still further the practical utility of that disease for field operations on a 
rge scale. In consequence of this outeome very few distributions of in- 
¢ted material have been made from my office during 1896, and those only in 
sponse to direct requests from farmers. The material sent out has been 
companied, as in all my previous sendings, with explicit warning to the 
fect that no definite reliance was to be placed on it, but that its use was to 
regarded as an experiment only. It now seems quite clear, as the general 
sult of all our investigations of this complicated subject, that the cireum- 
meces under which artificial field infection of chinch-bugs with the white- 
ascardine fungus will take practical effect ina way to produce any important 
nefit are at least so rare and unusual that the whole subject must at present 
“assigned to the limbo of unverified theories. 
A more promising result was obtained from an investigation of a bacterial 
sease of the common squash-bug, which proved to be highly contagious and 
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