INFECTION EXPERIMENTS IN LABORATORY. 
23 
All bugs were collected at Cherryvale, a locality that showed an 
abundance of Sporotrichum in the soil ; hence the positive results in 
the check bottles. The experiment began May 7, and by May 24 all 
the bugs in all the bottles were dead. 
The results are tabulated below : 
BOTTLES 1 TO 10. 
Bottle No 
1 
2 
3 
4 
5 
6 
7 
8 
9 
10 
Date. 
Number of diseased bugs. 
May 10 
May 13 
1 
1 
1 
May 16 
1 
1 
May 24 
1 
2 
1 
.... 
1 
2 
1 
Total number of diseased bugs., 13. 
BOTTLES 11 TO 20. 
Bottle No 
11 
12 
13 
14 
15 
16 
17 
18 
19 
20 
Date. 
Number of diseased bugs. 
MavlO 
? 
1 
1 
1 
3 
"2 
1 
"2 
2 
1 
May 13 
1 
1 
1 
1 
2 
1 
1 
1 
6 
2 
2 
4 
2 
2 
May 16 
4 
May 24 
1 
1 
4 
Total number of diseased bugs, 53. 
•* 
BOTTLES 21 TO 30. 
Bottle No 
21 
22 
23 
24 
25 
26 
27 
28 
29 
30 
Date. 
Number of diseased bugs. 
May 10 
May 13 
1 
2 
3 
1 
2 
10 
i i 
May 16 
1 
May 24 
17 
6 
11 
1 
3 
is 1 6 
15 
9 
Total number of diseased bugs, 105. 
It is possible that bottles 21-30 had more spores attached to them 
than those in the other bottles, but that the spores possessed viru- 
lence is shown by the results in mortality. 
Experiment 4- — This experiment was begun May 17. Forty-eight 
screw-capped bottles, each containing an equal amount of earth, 
were sterilized in an autoclave. Twelve adult chinch bugs were then 
placed in each bottle. Twenty-four bottles were kept as checks 
(uninoculated), and 24 were inoculated as follows: Thirteen bottles 
by allowing bugs to crawl over spores from a culture and 11 bottles 
by scattering similar spores into the bottles with a camel's-hair 
brush. The brush was rolled in a mass of the spores in a petri-dish 
culture and then struck sharply against the lip of the bottle. A cloud 
