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tato vines, where the female deposits the eggs for the third 
and last generation. The larvee from this generation enter the 
ground when full grown, transform to pupze, and soon after to 
_ perfect insects. This perfect insect, or a beetle of the third 
generation, does not, however, leave its cell in the ground, but 
remains there until the following spring. 
In some cases these beetles have been badly fooled by the 
weather, showing that their instinct is not infallible, Three years 
ago we had avery early and severe frost lasting several days. 
After this frost it became very warm again, in fact we had a 
second summer lasting many weeks. his warm weather fol- 
lowing a severe frost—winter—invited the beetles to leave the 
ground. Ofcourse all beetles that left their wintering quarters 
perished from hunger, or later by frost. Knowing the natural 
history of this insect it is, of course, very easy to account for 
the fact that few or no potato-bugs could be found in the spring 
of 1895. Whoever recollects the continuous drouth of the sum- 
mer and early fall of 1894 will also recollect that the foliage of 
the potatoes had disappeared almost entirely early in the sum- 
mer, and that consequently there was very little food for the 
potato-beetle to produce a third generation. In fact a great 
number of larvae of the second generation already failed to find 
sufficient food to mature. Other larvae that had fared better 
were actually killed upon the heated and baked surface of the 
ground, not being able to dig their way into such a hard sub- 
stance. There being no third generation, of course there were 
no hibernating beetles, and nonecould be found at the time the 
new potato plants commenced to grow in 1895. These condi- 
tions prevailed in almost all parts of this and adjoining states, 
and it would have been a very lucky thing if certain localities 
had not formed an exception; but such was the case, and nu- 
merous farms near lakes and rivers, or where the soil retained 
moisture throughout the summer, not only produced good crops 
of potatoes but equally good crops of beetles. 
In 1895 such places formed centers from which the potato- 
beetle spread and wherever farmers permitted them to do so, 
they have again infested large areas. It would have been a 
very good thing if the state had a law that would have forced 
farmers to kill the few potato-bugs that were seen in the fields, 
because an opportunity like the past one, in which an insect 
