48 



PAPEES ON CEREAL AND FORAGE INSECTS. 



From this table it is seen that while the check cages gave but 1.45 

 per cent developing the fungus, this percentage was raised to 14.28 

 when the bugs were artificially inoculated. 



Some live and apparently healthy bugs were then killed mechan- 

 ically by piercing them with a sharp needle, their bodies then being 

 inoculated with the fungus and placed on moist blotting paper. 



Inoculation experiments with bugs hilled mechanically . 



Artificially inoculated. 



Number 

 bugs used. 



Number 



developing 



fungus. 



Per cent 



which 



developed 



fungus. 



25 

 35 



25 



4 

 3 

 3 



16 



8.57 

 12 



85 



10 



11.76 



Check. 



50 











Others were killed with fumes of chloroform, allowed to dry over- 

 night, then washed in distilled water, and treated as in the preceding 

 experiment. 



Inoculation experiments with bugs Trilled with fumes of chloroform. 



Artificially inoculated. 



Number 

 bugs used. 



Number 



developing 



fungus. 



Per cent 



which 



developed 



fungus. 



20 

 25 

 20 



6 30 



5 20 



6 30 



65 



17 



26.15 



Check. 



200 











From these experiments with dead bugs it was found that a small 

 percentage of them could be made to produce Sporotrichum globuliferum 

 after inoculation, with every indication that the fungus made its en- 

 tire growth on their dead bodies. 



Experiments with live chinch bugs. — The cages used in these 

 experiments consisted of a series of small flowerpots containing grow- 

 ing wheat, over each of which was placed a glass cylinder. Into 



