136 
food supply was short, and when the moisture was also sufficient 
for the germination of any spores of the white fungus that may 
have been present. 
Mr. Hurd wrote the office, November 20, that the disease was 
still present in these shocks, and that he had collected an abundant 
supply for use next spring. 
__ No - 77, T £j 8 is a farmer ’s field contagion experiment made by 
Mr George W. Heth on his farm (see PI. III.) about five miles 
west of Edgewood, in West township, in the extreme southwest 
corner of Effingham county. It is the last of the three exceptional 
cases of the development of white muscardine in the field to 
which reference has already been made. 
The material used in this experiment was derived from two 
original sources, the first, a small number of chinch-bugs dead 
with Sporotrichum received by Mr. Heth May 15, from Chancel¬ 
lor Snow, of the University of Kansas; the second, similar ma¬ 
terial sent him early in June from my office, from No. 54 of this 
series. The fungus-covered specimens received from Kansas were 
scattered directly (May 15) among chinch-bags in wheat (see A, 
El. HI.) at about the center of the field. The bugs were very 
abundant at the time, practically covering the wheat everywhere 
throughout the field. A slight rain fell May 17, followed by 
heavy storms on each succeeding day until the 20th. The fungus 
did not seem to spread, and the chinch-bug attack became daily 
more intense. Dry weather followed until the middle of June 
when, according to Mr. Heth’s observations, no traces of disease 
could be found in the field. In the meantime the second lot of 
specimens above mentioned, derived from No. 54, had been placed 
by Mr. Heth in a large pasteboard box stocked June 10 in the 
usual manner for infection purposes, but, according to his some¬ 
what vague statement, without very successful results. Several 
days afterwards Mr. Heth began to distribute this material in his 
wheat. ‘T removed some of the insects from the box,” he says, 
“part of which were white with fungus, every second day, and 
scattered them over the ground near the center of the wheat field 
A, where the bugs were extremely thick. These distributions 
were made in the evening and were kept up for about a week, 
but the soil was very dry.” Rains fell on the 16th and 17th of 
June, but no traces of muscardine could be found on the 18th, or 
at the time when the wheat was cut, June 25. The ground was, 
in fact, in many places almost black with living chinch-bugs at 
that time, and there was a general movement to the north & and 
east into corn fields adjoining (marked B and C on PI. III.), the 
greater number going, however, into field C, where the corn was 
piesently almost completely destroyed. The destructive horde 
passed thence successively into fields D, E, F, and G, where they 
continued their ravages until late in the fall. 
On September 25, while examining the grass in the orchard F, 
at the point a, Mr. Johnson discovered many dead chinch-bugs 
on the ground under the stools of grass thickly enveloped in a 
dense, fresh growth of Sporotrichum. Half a dozen whitened 
