62 



On the same day this experiment was began, a second was also com- 

 menced, like the iirst in every particular except that the healthy bugs 

 used, in experimentation, were exposed to fungus iufested individuals 

 for only five hours, and then placed under their respective glasses. As 

 a result on August 15, thirteen days after, none had died, thus strongly 

 indicating that the Entomophthora did not exist generally in the fields, 

 and that it could not be communicated during a period of five hours, 

 exposure. 



On August 7 a large number of healthy bugs were placed under 

 glass, with a number which had recently died from Entomophthora, the 

 moisture in the vessel being absorbed by calcium chloride. A check 

 experiment was also commenced, where the material and the condi- 

 tions were the same, except the humidity of the atmosphere, care being 

 taken to have the latter as nearly saturated with moisture as possible. 

 August 10, the original experiment was divided and a portion of the 

 healthy bugs removed and placed in a damp environment, the remain- 

 der being kept under the original dry conditions. The results on 

 August 22 were as follows. In the original experiment, where the 

 healthy bugs had been continually in dry quarters, not a single bug- 

 had died from Entomophthora. Not only this, but none of those which 

 had been removed after three days and placed in dry quarters had died, 

 showing that the disease was not contracted and did not develop in 

 healthy bugs, though kept exposed in a dry atmosphere for fifteen 

 days, nor could it be originated by placing, in a damp atmosphere, for 

 twelve days, bugs which had been exposed to contagion for three days 

 in dry quarters. The results with the check experiment were quite dif- 

 ferent. Within five days after being confined with the Entomophthora, 

 the healthy bugs began to die from effects of the disease, and in three 

 days more every one had died from the same cause, their bodies being 

 covered with spores. 



Still another experiment was tried which consisted in confining a 

 large number of healthy bugs with others diseased in a damp environ- 

 ment, and when the fungus had destroyed a portion the remainder were 

 divided and a part removed to dry quarters. The result was that while 

 those left in damp confinement continued to die, none of those inclosed 

 in dry environment were destroyed. As the fungus had by this time be- 

 come distributed over the experiment farm so that I could not tell with 

 certainty whether material from the fields was in a perfectly healthy 

 condition or not, no farther experiments were made in this direction. 



From the foregoing it will be observed that the essential element in 

 all of these experiments was an abundance of moisture, without which 

 the Entomophthora could neither become established nor flourish alter 

 it had gained a footing. Again the extent to which the disease will 

 prove contagious will depend upon the number of bugs. Without 

 great numbers massed together comparatively few would contract the 

 disease. To sum up the matter there is little hope for relief to the 

 farmer from the influence of Entomophthora, except when Chinch Bugs 



