FLORIDA ,ST ATE HORTICULTURAL SOCIETY. 
81 
come of such a search may he, but we can 
never know until we find out by actually 
making the search. Should no more ef¬ 
fective parasites (insect or fungus) be 
found, the negative results would still be 
of value. The hope of relief from nat¬ 
ural enemies more effective than the ones 
known at present would be disposed of, 
and this would probably result in making 
more efficient use of the means of con¬ 
trol already at hand. One thing is quite 
certain, that the task of finding a more 
effective natural enemy of the whitefly in 
its native home may prove a most difficult 
one and require a more or less protracted 
search. 
While, as stated, the higher points of 
the whitefly problem appear to have been 
touched, there still remains a considerable 
number of smaller problems that need to 
be solved and the finishing touches made. 
The conclusions of previous experiments 
and observations need to be continually 
verified in relation to different localities 
and varying seasons. Some of the minor 
problems may prove to be high points, 
and we cannot always know of how great 
importance a new discovery may be until 
we have made it and know some of the 
facts connected with it. The discovery 
of the cloudy-winged species appeared at 
first to be of but little practical importance 
until it was found that the yellow fungus 
thrives upon it only, and that it differs 
from the white-winged species by appar¬ 
ently not having any food plants except 
citrus. These facts, together with the 
knowledge that the cloudy-winged species 
is less virulent, are of some importance 
when adapting repressive measures. 
METHODS OF CONTROL. 
The subject of fumigation with hydro¬ 
cyanic acid gas will not be specially dis¬ 
cussed, but referred to in its proper place, 
because Dr. E. A. Back, one of Dr. Mor¬ 
rill’s associates in the fumigation work is 
present this evening, and can answer all 
questions on this subject. Besides, bul¬ 
letin 76 of the Bureau of Entomology, 
U. S. D. A., can still be obtained by send¬ 
ing 15 cents to the Supt. of Public Docu¬ 
ments, Washington, D. C. This bulle¬ 
tin, by Dr. A. W. Morrill, gives the nec¬ 
essary information on fumigation. 
Since the speaker has recently had oc¬ 
casion to discuss the different phases of 
control, both in speech and writing, it fol¬ 
lows that what he has to say on this sub¬ 
ject tonight will be a repetition to many. 
On the subject of control the speaker fur¬ 
ther prefers to quote from a manuscript 
intended as the next Experiment Station 
Bulletin on whitefly (Bulletin 103). 
THE FUNGUS DISEASES. 
It is a well established fact, but not so well 
known, that insects are subject to diseases as 
well as other animals and men. Among the 
principal disease producing agents of insects are 
certain parasitic fungi, and the whitefly fortu¬ 
nately is subject to attack by about six. These 
are the Red Fungus ( Aschersonia aleyrodes), 
Yellow Fungus ( Aschersonia flovo-citrina ), 
Brown Fungus ( Aegerita webberi Fawcett), 
Cinnamon Fungus (Verticillium heterocladum ), 
White Fringe Fungus ( Microcera sp.), and oc¬ 
casionally a species of Sporotrichum, related to 
the Chinchbug Fungus. These are all parasites 
of the larvae of whitefly, except the last one, 
which has occasionally been found infecting dead 
adult whiteflies and presumably had caused their 
death. 
As it would fall without the scope of this pa¬ 
per to fully discuss each of these fungi, the Red 
Aschersonia will be alone treated in some detail 
followed by only brief statements on the others. 
The Red Aschersonia .—‘This fungus has giv¬ 
en satisfactory results in localities where the 
summer rains were normal, or where the trees 
