ARTIFICIAL INFECTION FIELD EXPERIMENTS. 37 
from 8 to 10 days, showing quite conclusively that the spores were 
present in the soil. 
In a field of wheat and in one of rye, west of the infected fields 
and about three-fourths of a mile distant from any of them, diseased 
bugs were found in the early part of June in as great numbers as in 
the Evans field just mentioned. The chance of material from my 
infections having reached these fields was very improbable. Several 
other fields were examined and none was free from infected bugs 
where bugs were plentiful in the period preceding harvest. But 
the proportion of diseased bugs varied considerably from field to 
field. And apparently in no case had the fungus produced an epi- 
demic sufficient to materially reduce the number of bugs or to save 
the crop. 
My experience with infection boxes was not such as to greatly 
encourage the infection idea. Living bugs were confined with dis- 
eased ones in boxes of moist earth for weeks at a time, and only a very 
few became infected. Later in the season, when the disease became 
common in the fields, it spread more readily in my boxes. 
My observations lead to the following conclusions : 
1. Sporotrichum occurred naturally in the soil of all of the fields. 
2. The distribution of the spores or of spore-covered bugs in a 
field had no noticeable effect upon the dying of bugs. 
3. Bugs died spontaneously when the weather was sufficiently moist 
and when the ripening of the grain diminished their food supply. 
4. Spontaneous infection did not spread to such an extent as to 
materially benefit the crop. 
The results attained in the precedinggreport were confirmed by ob- 
servations made during the experiments. The results fully accord 
with those obtained elsewhere, and are of particular value because of 
the favorable moisture conditions and the larger number of chinch 
bugs. In the Evans field the young bugs suffered more severely by 
attacks of the fungus than in any other field investigated. 
Weather conditions for Cherryvale and Independence. — The 
weather statistics for these two centers of experimental work were 
gathered by Mr. F. L. Kenoyer, of Independence, and we hereby 
express our thanks to him for his kindness in taking humidity read- 
ings and furnishing a copy of the precipitation record. During the 
month of May and the fore part of June, southeastern Kansas had a 
rainfall in excess of the average and a relatively high humidity. 
The soil in this section, being mostly heavy, retained the moisture 
well. The conditions for fungus propagation seemed to be ideal dur- 
ing a part, at least, of the period of growth of the new brood of 
chinch bugs. While adults seemed to succumb first, many young 
were affected, especially at Independence. 
