22 THE WHITE-FUNGUS DISEASE IN KANSAS. 
Experiment 1, — This experiment was started April 29, the bugs 
being collected at Colony, a locality which showed an extraordinarily 
small amount of Sporotrichum in the soil when compared with other 
localities (except Garnett, in the same county). By selecting bugs 
from Colony it was hoped to avoid, as far as possible, the presence of 
spores on the bugs or in the soil before the experiment began. The 
insects were collected in five sterile bottles, with an approximately 
equal quantity in each. One bottle was infected with spores from an 
artificially grown culture. The other four bottles were not opened 
after they were sealed in the field. By May 13 three diseased bugs 
were noted in the infected bottle. Four days later all the bugs in 
the bottle were dead and about half of them were covered with a 
visible and typical growth of Sporotrichum. The bugs were dead 
in the four check bottles, but no fungus developed. 
Experiment 2. — This experiment was designed to reach the same 
as the previous one, but by a different method. It began May 7. 
Six screw-capped bottles, each containing 100 grams of earth, were 
sterilized in an autoclave. Bugs direct from the field and not arti- 
ficially infected were placed in three of them. To the other three 
bottles were added bugs, in approximately equal numbers, which had 
been allowed to crawl for two hours over a moist Sporotrichum 
culture. 
Final observations were taken 10 days later. In the uninfected 
bottles no fungus developed. Two of the other three contained two 
and eight diseased bugs, respectively. No fungus appeared on the 
third. The short period of 10 days duration to an extent eliminated 
deaths by Sporotrichum resulting from extreme weakness due to pro- 
longed incarceration and starvation. 
Experiment 3. — This experiment was designed to compare the rela- 
tive effectiveness of fungus grown on a culture medium and that 
arising naturally on chinch bugs. Thirty screw-capped bottles were 
prepared with 100 grams of soil in each bottle, then the whole was 
sterilized in the autoclave. About 18 chinch bugs were placed in 
each bottle. A sterile pair of forceps was used to transfer the bugs, 
and unsterilized field earth was avoided as far as possible. Bottles 
1 to 10 were checks, No. 10 having no infected material added. Bot- 
tle 11 contained bugs which had been shaken up in a small box with 
three fungus-covered bugs which were finally added to the bottle 
before it was sealed. Bottle 12 was prepared in the same manner. 
Bottles 13-17 contained bugs that had been shaken up with a lot of 
crushed diseased bugs. Bottles 18-20 contained bugs that had been 
shaken up with soil which had previously been made infectious by 
rubbing up diseased bugs in it. Bottles 21-30 contained bugs that 
had been allowed to crawl over a mass of Sporotrichum grown on 
culture medium. 
