34 
NATURAL CONTROL OF WHITE FLIES IN FLORIDA. 
11 that these same dead pupae had developed the characteristic 
growth known as white-fringe fungus. During 1908 and the summer 
of 1909 the authors found the fungus in every grove visited in various 
parts of the State. 
Since the observations made on November 26, 1906, this fungus 
has been regarded by the authors as entirely or largely saprophytic, 
and all data and observations since obtained have strengthened this 
belief. Three series of observations have been conducted in connec- 
tion with fumigation experiments. The data obtained are presented 
in Tables VII and VIII. Specimens of the fungus under observation 
were submitted to Prof. H. S. Fawcett, who verified the authors' 
determination of the species. The data in Table VI are based upon 
the examination, by the senior author and Mr. W. W. Yothers, of 
leaves picked promiscuously from adjoining fumigated and unfumi- 
gated rows of nursery trees. The trees were fumigated on September 
26, 1908, and the examination was made on October 8, 1908. 
Table VI. — Relative abundance of white-fringe fungus on fumigated and unfumigated 
leaves. 
Leaves. 
Number 
of leaves 
exam- 
ined. 
Live 
pupae. 
Dead 
pupae. 
Pupae infected with white- 
fringe fungus. 
Total. 
Average 
per leaf. 
Per cent. 
20 
20 
2,154 
19 
1,031 
4,432 
29 
302 
1.4 
15.1 
0.9 
6.8 
In Table VII are given data collected by Mr. Yothers showing the 
development of the fungus over a period of one month on fumigated 
leaves, as compared with the same on unfumigated leaves. Five 
selected leaves were under observation in each case. 
Table VII. — Development of white-fringe fungus on fumigated and unfumigated leaves . 
Fumigated October 12, 1908. 1 
Unfumigated. 2 
Leaf No. 
Pupae infected on— 
Leaf 
No. 
Pupae infected on— 
Oct. 13. 
Oct. 26. 
Nov. 9. 
Oct. 13. 
Oct. 26. 
Nov. 9. 
1 

1 
4 
1 

1 
4 
8 
13 
1 
2 
12 
8 
20 
29 
6 
7 
8 
9 
10 

3 
1 

1 

4 
3 

4 

2 
4 
3 
3 
4 

5 
4 
Total. 
6 
27 
CI 
5 
11 
11 
i Leaves 1 to 3 on one nursery tree with a total of 400 dead and 2 living pupae. Leaf No. 4 on similar tree 
and with same number dead and living pupae. Leaf No. 5 on similar tree but with 1 living and 400 dead 
pupae. 
2 Leaves 6 to 10 with average of about 40 living pupae and numerous dead larvae and pupae per leaf. 
