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JOURNAL OF ECONOMIC ENTOMOLOGY 
[Vol. 11 
equivalent to 1/100 ton of hay. Using this as a basis we may figure 
that an average of one hopper per square yard may destroy the equiva¬ 
lent of three pounds of alfalfa hay per acre per day. In a forty-acre 
field a moderate infestation averaging 16§ hoppers per yard may de¬ 
stroy the equivalent of one ton of alfalfa hay per day. We may also 
figure that at present market Values for alfalfa hay in Arizona, the cost 
of using poison bait is considerably less than the damage done in a 
single day by adult differential grasshoppers occurring at the rate of 
16| per square yard. It is evidently very profitable to poison the 
hoppers even when they average as few as 5 per square yard. 
It is unnecessary to say that calculations of this kind prove very 
effective in connection with demonstration work in grasshopper con¬ 
trol, particularly when the infestations are not conspicuously heavy; 
President R. A. Cooley: Do you wish to ask Dr. Morrill any 
questions or to discuss this contribution? 
The points covered by Dr. Morrill are certainly of much interest 
and very valuable in practical work in the field among farmers. We 
learned that this past season in our grasshopper experiences. I am 
particularly glad that this work was undertaken. 
The next paper is by Mr. W. P. Flint, of Illinois—“ A New Method 
of Combating the Chinch-Bug.” 
SUGGESTIONS FOR A NEW METHOD OF DESTROYING 
CHINCH-BUGS 
By Wesley P. Flint, Assistant, State Entomological Survey 
This paper is given not with the idea of showing the results of a 
finished series of experiments, but as suggesting a possible new point 
of attack on one of our most destructive grain insects. 
During field operations against the chinch-bug in Illinois, when 
immense numbers of these insects had been confined for some days in 
dry stubble fields, it was noticed that they would collect in large num¬ 
bers on any moist object or on the ground where water had been spilled. 
A close examination of a large number of chinch-bugs that were gath¬ 
ered on a moist gunny sack used to protect a water jug showed that 
nearly all had their beaks inserted in the sack and were apparently 
sucking the water from it. From these observations it seemed pos¬ 
sible that chinch-bugs might be killed if they could be induced to feed 
on some substance which was moistened with water containing some 
soluble poison. 
