18 Contagious Diseases of the Chinch-bug. 
the spores in suspension was poured into 10 gallons of water and 
distributed over the fields by means of a spraying apparatus. It 
was found that by this dilution one or more spores could be found 
in a single drop of the water. The experiment was varied by 
sprouting spores over night in a sugar solution before spray- 
ing. At the same time experiments of a like nature were car- 
ried on in the laboratory. For this purpose flower-pots half 
filled with friable garden soil and closed at the top with cotton 
batting were sterilized in a hot-air oven. The soil was then 
wet with boiled water, then the bugs were put into the pots, 
then the infection, and finally the sterilized cotton was tied 
over the mouth of the jar. Bugs from one locality only in 
most instances were used in a single set of experiments. An 
account of the laboratory experiments will be briefly stated. 
IV.—LABORATORY EXPERIMENTS. 
Kxperiment 1. March 19 eight pots were started, haying 
been prepared as stated above. 
(a) Two pots were watered with boiled water, but left unin- 
oculated, to serve as checks. 
(b) Two pots were infected with fungus-covered bugs. 
(c) Two pots were sprayed with culture from potato. 
(d) Two pots were sprayed with culture from potato after 
the spores had been sprouted in sugar solution. 
The bugs slowly died of Sporotrichum in all the pots, the 
checks showing no material difference. | 
Hxperiment 2. April 22 bugs that had been received from 
various parts of the state were put into a large box until they 
had intermingled and then were distributed as equally as pos- 
sible among 12 pots. 
(a) Three were left uninoculated as checks. 
(b) Three were inoculated with fungus-covered bugs. 
(c) Three, were sprayed with spores of artificial culture on 
turnip. 
(d) Three were sprayed with sprouted spores from turnip 
culture. 
Bugs in all the pots slowly died of Sporotrichum, the checks 
showing no essential difference. 
