\ 
26 Contagious Diseases of the Chinch-bug. 
bugs were taken, there having been many dead bugs there on 
the 17th, but few since. 
June 20. Sprayed the bugs with sprouted spore-solution. 
June 21. Bugs seem to be dying slowly, and white ones are 
gradually getting thicker on the surface of the soil. 
June 22. Sprayed with sprouted spores. Open box No. 2 
started. This might more properly be called a table, as the 
sides were only an inch high—just enough to hold in the dirt. 
This box was about 10 feet long by 3 feet wide, and was divided 
into three sections. The bugs, taken as before from the corn- 
field, were kept in the box and prevented from crossing the lines | 
dividing the three sections by means of a line of tar. This line 
was about one inch wide, and was renewed daily. Two pots of 
corn were placed in each section. Section A was sprayed with 
ordinary artificial culture. Section B was infected with dis- 
eased bugs. Section C was sprayed with sprouted spores. This 
box was also placed so as to be in the sunlight a few hours each 
afternoon. 
June 23. Nothing new in box 1. No results in box 2. 
June 24. Bugs in box 1 had for several days been gathering 
in large numbers in the corners of the box, as well as on the 
corn. Many of them were moulting, and newly-winged bugs 
could be seen. A few bugs were dying every day. Box 2, no 
results. Fresh corn putin. Tar-line renewed. 
June 25. Box 1. The soil was thickly speckled with white 
bugs, but they were not perceptibly more numerous than the 
day before. Box 2. Noresults yet. The bugs in box 1 have 
almost all reached the adult stage. / 
June 26. No increase of Sporotrichum in box 1, but large 
numbers of bugs covered with Empusa aphidis. Ground coy- 
ered in one corner of box, and many bugs stuck on the pots. 
Very sudden and remarkable growth. Box 2 had a few Sporo- 
trichum bugs in each section. 
June 27. A slight increase of Empusa in box 1; no change 
in Sporotrichum. Box 2 showed no increase of Sporotrichum. 
Some of the winged bugs escaped over the tar. One Empusa 
bug was found on a pot in C in the morning, and several more 
in the afternoon. No Empusa had yet been noticed in the 
closed boxes. It developed perceptibly in box 1 during the 
day. 
