50 XATUEAL CONTROL OF WHITE FLIES IX FLOEIDA. 
fungous leaf, the authors conclude that showers and abundance of 
larva? and pupa? are conditions most favorable to successful pinning. 
Good infections have been secured at times when there were no adults 
on the leaves. 
While there are cases on record where very good results hi intro- 
ducing fungus have followed the pinning method, this must be 
regarded as second in importance to the introduction of spores in 
water mixtures, especially when Aschersonias are concerned. On the 
other hand, infections with the brown fungus have been secured with 
more certainty by pinning than by spraying, although with no more 
certainty and in a less widespread manner than by the dipping of 
infested shoots into ground brown-fungus leaves and water as de- 
scribed elsewhere. Infections with brown fungus by pinning have 
been secured as late in season as Xovember 6 (1908). 
Infections secured by rubbing fungus-infected leaves, as described 
under experimental methods, have proved of more value hi connec- 
tion with the brown fungus. Although success has attended the 
introduction of the Aschersonias by this method, they are too easily 
introduced by water mixtures to warrant attempts at introducing 
them by rubbing. Under favorable weather conditions the rubbing 
method is many times superior to the piniiing. At most, nibbing, 
even for brown fungus, is a very uncertain method, as only a very 
small percentage of leaves rubbed become infected. In a hammock 
grove at St. Augustine. Fla., in August, 1907, the senior author 
rubbed about 1,200 leaves on four trees, the leaves averaging about 75 
citri larva? and pupae. Infection resulted only on about two twigs. 
Later in the season slightly better results have been obtained. When 
only a few brown-fungus-infected leaves are obtainable, they can best 
be used for rubbing and then pinning. Frequently leaves that appear 
to have been rendered worthless by rubbing have caused infections 
when pinned. Fungous leaves should be kept wet or moist during 
rubbing by frequently dipping in water. Good infections with 
brown fungus have been secured as early as June 5, 1907, and as late 
as October 31, 190S, although September and October have proved 
more favorable months than the three preceding. While Prof. Faw- 
cett reports 1 success hi obtaining infections by means of the brown- 
ish sporodochia, which are found dusted over the surfaces of the 
infected leaves, several similar tests by the authors made at various 
times since June, 1907, have all been without results. 
WATER MIXTURES OF SPORES AND MYCELIA. 
Preparation of mixture. — Whichever of the three most promising 
methods of introducing the fungi hi water mixtures is to be followed, 
viz, spraying, dipping, or brushing, the initial steps in the preparation 
of the mixture, with few exceptions, are the same. The "fungous 
i Science, vol. 31, no. 806. p. 913, 1910. 
