THE BROWN FUNGUS. 31 



that tho spi-ead of l'iiii<^iis from tn'-o to troo was on'octcd through 

 fragments of the mycelium carried by wind or birds. It has been 

 conchisively demonstrated by means of a series of marked specimens 

 that Dr. Webber's observations as to the power of infection possessed 

 by the mycehal lihiments is correct. In several instances infection 

 wasiioted to occur only so far as the mycelial growth extended. In 

 this respect the mycelia of the Aschei-sonias is different; living 

 piipte have frequently been noted to touch developing pustules of 

 both red and yellow Aschereonia without becommg infected. 



^Vlule it is very likely that winds, birds, and insects do spread this 

 fungus by canyuig small i)ieces of mycelium on tlieir bodies, the 

 experiments of the authore and of Dr. Berger have fully demon- 

 strated that the fungus can be spread from grove to grove by means 

 of broken pieces of mycelimn. It has been frequently observed that 

 the fungus appeare on trees to which no attempt has been made to 

 mtroduce it. As yet no success has followed the attempt on the 

 part of the authors to si)read tlie fungus by means of the spores 

 already mentioned, but consideruig the abundance with which they 

 are developed, esi)ecially after the middle of July, it is conside- a 

 probable that they play an important, though as yet imknoAvn part 

 in its dissemuiation.^ Although it probably will be proved that ths 

 broNvn fungus is most widely dissemmated 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- 

 mg mycelium. As noted elsewhere, these mycelial filaments have 

 been traced from one leaf do\vn 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 fuid 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 m any amount in a grove infested by any other species. 

 However, slight uifections of the cloudy- wmged white fly have been 

 noted in various places. 



DISTRIBUTION. 



The brown fungus has been introduced into or reported from the fol- 

 lowing places m Florida: Lake City, St. Augustine, Hawthorn, 

 Mcintosh, Boardman, Leesburg, Orlando, Oviedo, Winter Park, 

 Bartow, Lakeland, Largo, St. Petereburg, Bradento^vn, Manatee, 

 Oneco, Palmetto, Sarasota, Alva, Buckingham, aiul Fort Myers. 

 In addition it has been introduced mto various places in Louisiana 



■ 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. 



