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leaves in the corn fields, around the lower ends of the stalks, 
and the like. Make this distribution, by preference, in the even- 
ing, when the dew is on, or, still better, just after a rain, and 
repeat if dry weather follows. Continue these collections and 
distributions as above through the whole season, making certain 
each time chinch bugs are taken out that white ones are left in 
the box; and when winter comes put all the dead bugs remain- 
ing into pill boxes for use the following year. 
‘‘Those wishing to form an independent judgment of the 
practical value of this method of dealing with chinch bugs 
should take into account the following facts: 
‘‘1. The white fungus causing insect disease requires moist- 
ure for its full development, and especially for the formation of 
the minute ‘‘spores” by whose dispersal the disease is conveyed 
from one insect to another. In times of severe drought it propa- 
gates slowly or not at all. 
‘2. It takes effect on a weakened insect more readily than 
on one in full vigor; on the full grown chinch bug more easily 
than on the young; and hence most easily of all on spent adults 
which have already laid their eggs and are about to perish by 
the natural termination of their life period. 
‘3. It is a native disease of the chinch bug, and never dies 
out entirely, but is likely to appear spontaneously over a large 
extent of country when conditions favorable to its development 
are long maintained. 
‘4. Two generations of the chinch bug appear each year, 
and when each of these generations matures, the adult bugs 
commonly take wing and scatter, thus disappearing largely 
from fields or parts of fields heavily infested by them. Such 
dispersal has often been mistaken for a destruction of chinch 
bugs by disease. One generation matures shortly after wheat 
harvest and the other in late summer and in the fall. 
«5. The chinch bug sheds its skin four times while growing, 
and the empty skins left by it are often mistaken for dead 
bugs— a mistake which has sometimes led to a false conclusion 
as to the effect of these infection experiments. The cast skins 
never bear wings, as the insect does not moult after its wings 
are formed. They may further be readily distinguished from 
the dead bugs by the fact that when pressed’ between the thumb- 
nails they are readily seen to be empty shells without contents. 
