133 
No. 74. August. 7. The second of this series of experiments 
was begun in a twenty-acre corn field (B, Plate IV.) owned by 
Mr. Silver, of Cincinnati, Ohio, and planted by Mr. Frank Robin¬ 
son, of Odin. This farm is about a mile and a half north of 
Odin, between the Ferguson farm on the south (No. 73) and the 
Hurd and Robinson farms on the north (Plate IV). The field 
was very dry and dusty; the corn thin, short, and very poor. 
Chinch-bugs just past the first moult covered nearly every stalk. 
A few adults were seen copulating. No traces of the fungus 
disease were seen. 
A row of dwarfed, sickly-looking corn along a dead furrow about 
the center of the field, thickly covered with bugs, was selected as 
a suitable place for the introduction of the infection. A piece of 
culture material from No. 2, about two inches wide by four inches 
long, containing a profuse growth of Sporotrichum, was cut into 
small fragments and placed among the bugs behind the leaves of 
every hill, for a distance of fifty paces, the spot being marked by 
clipping the tassels from the hills at either end. 
Examined August 18 by Mr. Johnson. No fungus-covered in¬ 
sects found. Some of the culture material still present. Corn in 
very bad condition and fiat on the ground in many places. 
Chinch bugs cover the corn throughout the field. Foxtail and 
other grasses literally alive with the insects. Weather very dry 
and hot. 
Second examination September 5, immediately after very heavy 
rain. Field very muddy. No traces of the infection material 
visible, and no bugs dead with the fungus seen. Corn crop an 
utter failure. Chinch-bugs seem to be increasing in numbers 
Selected another row along a dead furrow, about five rods from 
the first, and distributed about one hundred fungus-covered bugs 
from experiment 68 behind the leaves for a distance of seventy- 
three paces, and marked as before. 
September 19, not a single insect dead with the white fungus 
found in this field after an hour’s diligent search. Corn about 
all dead. Chinch-bugs still very abundant, but many going into 
meadows on the north and east. Few adults seen flying. 
September 26, about as before, except that the corn is all dead 
and chinch-bugs less numerous. No dead seen, and not a trace 
of the fungus found. Chinch-bugs very abundant in the adjoin¬ 
ing meadows, and considerable grass killed. 
The final visit for the season was made October 6. About one 
fourth of the corn had been cut and shocked and saved for fod¬ 
der; the other three fourths was flat on the ground, dead and 
brown. Chinch-bugs, mostly adult and pupae, were quite numer¬ 
ous in the shocks, and on the fallen corn throughout the field. 
Half a dozen bugs dead with Sporotrichum were picked up on 
the ground under a corn shock about two rods from the place 
where the last lot of infection material had been introduced, and 
a few others vere found at various points in the field, under 
shocks and fallen corn, but this was all. The presence of the 
fungus on chinch-bugs in this field at this time did not seem to 
