26 
these can be immersed for many days without being killed. 
But a wet season will rapidly lower the vitality of the chinch- 
bugs, and dispose them to contract the disease. 
Judging from a large number of letters the writers were well 
pleased with the results of spreading spores among chinch- 
bugs. In many cases the disease spread rapidly and effectively, 
in others the results became not apparent until rain assisted. 
Of course it would be folly to claim that the disease was always 
spread by the introduction of such spores, and it is also possi- 
ble that it would appear simply because the climatic conditions 
were in its favor. Whatever may be the reason of its appear- 
ance, so many farmers believe in the effectiveness of an intro- 
duction of spores causing the disease, that the state can well 
afford to continue this work, as the expenses of producing 
spores on a large scale are but small. 
MAP SHOWING DISTRIBUTION OF CHINCH-BUGS. 
The map shown in fig. 14 was made by Mr. Vincent Bailey 
to indicate the distribution of the chinch-bugs during the last 
two years, as well as during the year 1887, when farmers lost 
as much as $6,790,821 by this insect alone. The region infested 
in 1887 is indicated by section-lining, that in 1894 by a dark 
line giving the extreme western and northern distribution, and 
that in 1895 by crosses in the counties invaded. It will be seen 
that as a very general rule the chinch-bugs did not invade the 
region in which only pines and other evergreens grow, but that 
all the more southern counties, which are well wooded with 
deciduous trees, are invaded. It will also be seen that farms 
located in the open prairies have in no case suffered from these 
insects, but that those regions that were formerly simply roll- 
ing prairies but are now more or less covered with patches of 
timber between the farms, are the very headquarters of such 
insects. In former years this region, bounded on the west 
' with dotted lines, was annually burned over, thus preventing 
the growth of timber; this has ceased, and the country is now 
occupied with numerous thrifty farms. Since the cessation of 
prairie fires the chinch-bugs find suitable shelters, which they 
do not in the open prairies, or at least not yet. But as these 
prairies are gradually occupied by farms, and as wind-breaks 
are grown everywhere, they will also in time offer winter-quar 
ters for chinch-bugs, and thus these insects will gradually oc- 
cupy a larger area. 
