SPOROTRICHUM. 
35 
In the third series of observations the junior author selected leaves 
on which all living pupae had been killed by fumigation. It is proba- 
ble that fungus had already infected a few dead pupae but had not 
broken out around the margin previous to fumigation; yet, consider- 
ing the comparatively few pupae becoming infected on unfumigated 
leaves as compared with the unusual number infected on fumigated 
trees, there is no doubt that the fungus developed for the most part 
after the pupae were killed by the gas. 
Table VIII. — Development of white-fringe fungus on leaves fumigated Sept. 26, 1906. 
Leaf No. 
Pupse 
alive. 
Pupse 
dead. 
Pupse infected with white-fringe fungus on— 
Sept. 30. 
Oct. 8. 
Oct. 14. 
Oct. 21. 
Oct. 28. 
Nov. 5. 
1 





200 
600 
200 
400 
100 





10 




32 
2 
8 
1 
1 
57 
21 
21 
10 
6 
57 
40 
48 
22 
6 
57 
2 
40 
3 
48 
4 
22 
5 
6 
Total 

1,500 

10 
44 
115 
173 
173 
Concerning the reported practical results in reducing the white 
flies, it may be said that the occurrence of a very high percentage 
of the dead larvae and pupae, especially of the cloudy-winged white 
fly, as already noted in -the grove of Mr. C. W. Hicks, where over 91 
per cent of the dead insects were infected, has no bearing on the 
parasitic nature of this fungus, since an equally high rate of mor- 
tality occurs in groves infested with the same species where very 
little white-fringe fungus can be found. Its prevalence is evidently 
only an indication of the extent of the occurrence of unexplained 
mortality. The data here presented are regarded by the authors 
as satisfactory evidence that the Microcera develops almost entirely 
or exclusively on larvae and pupae already dead from other causes 
and should be disregarded as a factor in the control of the white fly. 
SPOROTRICHUM. 
The Sporotrichum is either closely related to or identical with one of 
the diseases of the chinch bug which attracted so much attention from 
entomologists a number of years ago. As a white-fly parasite it 
has been under observation since September 8, 1906, and is largely 
limited in its spread to the fall of the year, when, under favorable 
weather conditions, it spreads with astonishing rapidity among 
adults of both the citrus and cloudy- winged white flies then crowding 
the new growth. Tins fungus does not form pustules like the red 
Aschersonia. Adults killed by it remain attached to the underside of 
the leaf, their bodies become shriveled, and in a short time the grayish 
mycelial threads of the fungus break through the body of the fly and 
