THE BROWN FUNGUS. 31 
that the spread of fungus from tree to tree was effected through 
fragments of the mycelium carried by wind or birds. It has been 
conclusively demonstrated by means of a series of marked specimens 
that Dr. Webber's observations as to the power of infection possessed 
by the mycelial filaments is correct. In several instances infection 
was noted to occur only so far as the mycelial growth extended. In 
this respect the mycelia of the Aschersonias is different; living 
pupae have frequently been noted to touch developing pustules of 
both red and yellow Aschersonia without becoming infected. 
While it is very likely that winds, birds, and insects do spread this 
fungus by carrying small pieces of mycelium on their bodies, the 
experiments of the authors and of Dr. Berger have fully demon- 
strated that the fungus can be spread from grove to grove by means 
of broken pieces of mycelium. It has been frequently observed that 
the fungus appears on trees to which no attempt has been made to 
introduce it. As yet no success has followed the attempt on the 
part of the authors to spread the fungus by means of the spores 
already mentioned, but considering the abundance with which they 
are developed, especially after the middle of July, it is considered 
probable that thoy play an important, though as yet unknown part 
hi its dissemination. 1 Although it probably will be proved that the 
brown fungus is most widely disseminated through the agency of 
the small spores, it is apparent that after becoming well established 
on a branch its spread is due chiefly to infection started by the spread- 
ing mycelium. As noted elsewhere, these mycelial filaments have 
been traced from one leaf down its petiole, along the branch to the 
next leaf, thence along its petiole to start an infection on its under- 
side. It is not a rare occurrence to find all the leaves on a watershoot 
or small branch thus connected by mycelial growths. 
SPECIES OP WHITE FLIES ATTACKED. 
The brown fungus thrives best on the citrus white fly and has never 
been observed hi any amount in a grove infested by any other species. 
However, slight infections of the cloudy-winged white fly have been 
noted in various places. 
DISTRIBUTION. 
The brown fungus has been introduced into or reported from the fol- 
lowing places in Florida: Lake City, St. Augustine, Hawthorn, 
Mcintosh, Boardman, Leesburg, Orlando, Oviedo, Winter Park, 
Bartow, Lakeland, Largo, St. Petersburg, Bradentown, Manatee, 
Oneco, Palmetto, Sarasota, Alva, Buckingham, and Fort Myers. 
In addition it has been introduced into various places in Louisiana 
1 Since this was written Prof. Fawcett has been able to infect larvae with mycelium grown from these 
spores, thus removing all doubt that they are a means of disseminating this fungus. 
