CHINCH BUG WEST OF MISSISSIPPI RIVER. AT 
in these cages, thus eliminating that source of infection. This indi- 
cates that the spores of the fungus were present on the bodies of the 
living bugs and were only awaiting favorable conditions for germi- 
nation and abundant growth. In allsuch cage experiments the fungus 
appeared only on the bodies of the chinch bugs that had died in the 
cages and were lying on the soil. 
In the experiments at Washington, D. C., it was desired to obtain 
a better knowledge of this fungus and its relation to dead bugs, in 
order to ascertain to what extent, if any, it will grow saprophytically 
upon their dead bodies. Also to observe the rate of mortality among 
live chinch bugs, placed in cages and artificially inoculated, as com- 
pared with those under sim- 
ilar cage conditions not so 
inoculated. In the artifi- 
cial inoculation, the fungus 
was applied by thoroughly 
dusting the bugs with the 
spores of the fungus by 
means of a small brush, or 
in other cases by shaking 
them about in a vial con- 
taining the fungus-covered 
chinch bugs. 
EXPERIMENTS WITH Fig. 15.—The chinch bug: Adults covered with “white 
DEAD CHINCH BUGS.—To fungus” (Sporotrichum globuliferum). Enlarged. (Origi- 
determine whether or not” 
Sporotrichum globuliferum would make its entire growth upon the 
dead bodies of chinch bugs, a large number of live bugs, collected 
from tufts of Andropogon scoparius, and which died while confined in 
a vial, were inoculated artificially and their bodies placed on moist 
blotting paper. The results of these artificial inoculations compared 
with their checks are here given. 

Inoculation experiments with dead bugs. 



Artificially inoculated. Checks. 
I Per cent - Per cent 
5 Number : ~ or : 
Number Hevalonign which Number pata el which 
bugs used. aera © developed || bugs used. es =| developed 
Cais fungus. Fa fungus. 
25 5 20) 100 2 J 
D5 1 4 200 2 ] 
25 5 20 25 0 
23 4 16 25 2 8 
40 5 | 12 25 Up eee aes 
40 OF Ly Re ae 
140 20 14. 28 115 ( 1.45 




