716 Report oF THE ENTOMOLOGIST OF THE 
every vine on that half of the field. All that was left to indicate 
that vines had ever been there were a few withered stalks and 
occasionally a half-grown, rotting fruit. By the Ist of October, 
nearly every vine had been destroyed. Along the line of attack 
which stretched almost straight across the patch from north to 
south the bugs were so thick one could hardly step on the ground 
without destroying very many of them. Although great num- 
bers were on the ground in sheltered places and on the under- 
sides of the vines, many were found congregated in groups on 
the under, and frequently on the upper surface of the leaves; 
especially those that had begun to wilt. Eggs were found in 
abundance early in September and young bugs as late as the 
Ist of October. Plate IL is from a photograph taken in this 
field. 
Owing to the great number of insects present and the 
different stages represented, this field furnished a very good 
opportunity for testing the effect of bisulphide of carbon upon 
the pests. Accordingly two fluid ounces of the carbon were 
poured into a shallow dish and placed near a fallen and withered 
leaf upon which were numerous squash-bugs of all sizes. A large 
sheet-iron bucket, which happened to be near at hand, about 
three feet across the top, was inverted over the whole and the 
edges forced into the ground to prevent the circulation of air. 
At the end of half an hour the bucket was removed and about 
50 bugs which were nearest the dish were apparently dead. 
Twenty-five of them, the older ones, revived soon after being 
exposed to the air. The carbon was only partially evaporated. 
Subsequent experiments, both in the field and laboratory, showed 
that a much less amount of carbon is sufficient but that the 
insects should be exposed to its fumes for a much longer time. 
- The young bugs are much more susceptible than the mature 
insects The weather was cool with a stiff breeze blowing. On 
a warm day the liquid would have evaporated more rapidly and 
thus been more effective. 
The experiment with pyrethrum powder was as follows: A 
badly-infested portion of the patch was selected and the powder 
applied full strength. A Leggett powder gun was used, and 
both young and old bugs were thoroughly dusted and, in some 
cases, completely covered. Although at first somewhat disturbed 
