48 



Four tests were made of the material, following the directions for 

 preparing and aj^plying that accompanied the tube. Two of these tests 

 were made in the laboratory in small glass root cages and two of the 

 tests were in outdoor plats. 



In the first laboratory experiment, May 26, about twenty larvae were 

 treated, ten of which were inclosed in a root cage two and one-half by 

 four feet deep, and ten in an outdoor plat. Examinations later showed 

 no result. 



At the same time a few treated larvae were placed in a glass root cage, 

 the earth in which had been sterilized by continued baking, anct kept 

 in the laboratory for the purpose of closer observation. One specimen 

 included in this cage was found to be covered with a small cyst of earth 

 filled with a mycelial growth and the larvae itself was covered with a 

 dense white growth of mycelia. Another grub in this same cage went 

 on and pupated and showed no signs of being affected by its treatment 

 nor from being in contact with the diseased larva. 



On June 23d another test was made, both in laboratory and field. 

 Twenty-three treated larvae were inclosed in a glass root cage 24 by 36 

 by 3i inches inside. This was filled with sterilized earth to within 6 

 inches of the top. The earth had been sterilized by heating in a hot 

 air oven from six to eight hours at 70° to 90° C. These were examined 

 August 28. Three live grubs were found and five beetles. A num- 

 ber of larvae, with no signs of growth, were observed dead on the sur- 

 face a few days after treatment, and it is probable that they had been 

 slightly injured before or during collecting, as they were picked up in 

 furrow after the plow. The outdoor experiment, as in the first case, 

 gave no result. 



It will be seen that the only successful inoculation was of a single 

 larva in a laboratory cage, and this diseased larva did not communicate 

 the disease to another in close proximity to it. The field experiments 

 showed no result whatever, though it can not be said but that larvae 

 became affected and escaped our notice in later examinations and that 

 the disease may appear hereafter. 



The tubes evideutly contain a small proportion of spores and a large 

 proportion of starch, so that it is possible the larvae did not all get an 

 inoculation with spores. 



