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coccophila) that attacks Aspidiotus perniciosus in Florida (U. S. A.) 

 has been the subject of some very interesting experiments to test the 

 possibility of communicating the disease to previously healthy colonies 

 of the insect. Dr. L. 0. Howard gives the following particulars of the 

 experiment* : — 



An interesting and important development of the past two seasons 7 

 work has been the identification and study of the parasitic fungus, 

 Sphaerostilbe coccophila. Professor Rolfs, of the Florida Station, has 

 devoted a bulletin largely to the consideration of this fungus, which, as 

 previously stated, seems to be prevalent throughout the Southern States. 

 He has shown experimentally that the fungus may be transferred to 

 trees affeoted with San Jose scale, and the disease produced among the 

 scales. His process was to inoculate acid bread with pure cultures of 

 the fungus, and three weeks later the application was made in the follow- 

 ing way : — A piece of the bread about an inch square was placed 

 in cold water and shaken until the bread was broken up and 

 the spores distributed in the water. This water was then applied 

 to the scaly tree by means ol a sponge, or cloth, or sprayed 

 on. The applications were made in Midsummer of 1896, and 

 observations were made as to the results late in E'ebruary, 

 1897. Four of his experiments resulted successfully, and three unsuc- 

 cessfully, while in the eight experiment the result was doubtful on ac- 

 count of the tree having died between the times of treatment and in- 

 spection. Twigs from Florida containing San Jose scales, infested by 

 the fungus, were sent to Mr. Horace Roberts, at Fellowship, N.J., 

 about the middle of June. On September v 5th Dr. Smith found the 

 fungus upon almost, if not quite, ail of the trees on which twigs had 

 been tied. A number of instances have come to our observation of the 

 death of the scale in a wholesale manner from the spontaneous work of 

 this disease, or from some other cause. For example, we received scale- 

 infested cuttings in January, 1897, from an orchard which was said to 

 have been freed from scales by this fungus disease. Careful examina- 

 tion showed that upon one cutting, out of 183 scales, but four were liv- 

 ing; on a second cutting, out of 723, but two were living; on a third 

 cutting, out of 579, but twenty-eight were living, giving thirty-four 

 living scales out of 1485 — a mortality rate of 97.7.' 



I have, myself, repeatedly succeeded in disseminating the disease 

 affecting Lecanium viride by tying branches with diseased insects on 

 to trees on which the bug had hitherto remained quite healthy. 



There are several methods by which spores of these parasitic fungi 

 may be disseminated. As in the last-mentioned experiment, they may 

 sometimes be communicated by merely transferring affected branches to 

 the nighbourhood of the healthy insects. In such cases the spores are 

 carried by the wind to their destination. But in some of these fungi 

 the spores are gelatinous and agglutinated, in which case the wind 

 would fail to disperse them. Fungi of this kind may be crushed up in 

 water and used as a spray; or artificial cultures may be made and mixed 

 with water, to be used in the same way. In the ordinary course of 

 nature these gelatinous spores are probably carried from tree to tree on 

 the feet of birds. 



* Bulletin, No. 12. (New Series) U. S. Dept. of Agriculture, (Div, of 

 Entomology.) 



