THE CHINCH BUG. 13 
hatching that the species is most susceptible to meteorological con- 
ditions. Frequent drenching rains during the hatching season are 
fatal to the pest almost to the extent of extermination, and it is due 
to this more than to any other influence that the chinch bug is kept 
within the limits of its present abundance and destructiveness. It 
matters little how great a number of these insects pass the winter 
in safety, provided there are sufficiently prolonged, drenching rains 
during the hatching period. Again, with an excessive abundance of 
individuals developing from the first generation, if at the time of the 
hatching of the young of the second generation there are frequent 
drenching rains, an outbreak the following year is prevented. Thus 
it is that although an outbreak may seem inevitable as the season 
for the ravages of the chinch bug draws near, there is often a radical 
reduction instead of an increase in numbers. The forecasting of 
chinch-bug outbreaks is therefore based wholly upon the uncertain 
forecasting, months in advance, of meteorological conditions that are 
likely to occur at certain periods. If the farmer would but watch 
the seasons he need not be taken unawares by chinch-bug outbreaks, 
as dry weather during the two breeding seasons is usually sufficient 
to precipitate an invasion the following year, providing that, at the 
critical period, cr time of hatching, rains do not destroy the young. 
The general statement may be made that throughout the Middle 
West a dry June followed by a dry August is favorable for the devel- 
opment of chinch bugs. These dates will of course vary, and must 
not be applied to the more southern or more northern localities. 
PARASITIC FUNGI. 
The fact that the abundance and consequent influence of fungous 
enemies of the chinch bug are almost entirely dependent upon 
meteorological conditions is sufficient to place them in a secondary 
position, even though they may, under favorable weather conditions, 
act as natural checks. 
Dr. Henry Shimer! long ago made the truthful and important 
statement that “this disease among the chinch bugs was associated 
with the long-continued wet, cloudy, cool weather that prevailed 
during the greater portion of the period of their development.”’ 
These are precisely the conditions under which these fungi have 
been observed to prove the most fatal to the chinch bug during 
recent years where their introduction among the host insects was 
accomplished by artificial means. Although Shimer probably never 
anticipated the artificial cultivation of his ‘disease’ and the results 
which have since been obtained from its artificial dissemination in 
the fields, yet his careful and painstaking studies must ever be 
1Shimer, Henry. Notes on Micropus (Lygarus) Leucopterus, Say (‘The Chinch Bug’’), With an 
account of the great epidemic disease of 1865 among insects. Jn Proc. Acad. Nat. Sci. Phila., v. 19, p. 75-80, 
May, 1867.. 
