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10 Contagious Diseases of the Chinch-bug. ; 
various portions of the state very frequently developed the dis- 
ease under proper conditions without artificial inoculation. 
4.—HEAVY RAINS AND THE CHINCH-BUG. 
The heavy, beating rains of the summer months enabled us 
to see more certainly than ever before that rains do not in them- 
selves destroy chinch-bugs in sufficient numbers to saye the 
crops. The disappearance of the bugs so often noticed after 
heavy rains is probably not so much due to the beating of the 
storm or the drowning of the bugs as to the progress of fungus 
diseases which may spring up naturally, as was noticed this 
year, when the ground is moist and the atmosphere is humid. 
5.—RELATION OF SOIL, DRAINAGE, ETC., TO FUNGUS DISEASES. 
After Sporotrichum and Empusa became established in the 
fields, the best results were noticed where the grain made the 
densest growth and where the ground was kept shaded and 
moist thereby. In many such situations the ground was fairly 
well covered with fungus-covered bugs. But in those fields 
where the stand of grain was thin and the soil subject to rapid 
drying, relatively fewer fungus-covered bugs could be found. 
The growth of the Sporotrichum and Empusa was also found 
to depend on the character of the soil and the natural drainage 
of the fields. Where the soil was clayey and subject to baking 
on the surface, the fungus was comparatively infrequent, but 
where the soil was friable and loose in other parts of the same 
field the fungus was prevalent. Elevated portions of a field 
were found to be less favorable to the growth of the fungus than 
lower-lying portions which were moist for a longer period. In 
some instances, the difference was so great as to amount to com- 
plete failure in the less favorable situations, so far as the eco- 
nomic value of the disease was concerned, while in the more 
favorable places in the same field the destruction of the bugs 
was sweeping and positive. 
It would appear from certain experiments that the ability of 
the. Sporotrichum to destroy bugs depends in some measure at 
least upon the condition of the bugs; but the elements of the 
problem are so complex that it is difficult to arrive at definite 
conclusions. It seems certain that bugs which have about run 
their life course succumb more readily than the younger and 
