N'OSEMA-DISEASE. 



45 



In the experiments honey was diluted with an equal quantity of 

 water and medicated.^ To the medicated solution Nosema apis was 

 added. This suspension was fed to a colony, usually within a half 

 hour from the time it was made. On each of four or five days imme- 

 diately following the inoculation, the colony was fed honey medicated 

 with the drug but free from Nosema apis. 



In Table XXVIII are summarized the experiments performed, 

 together with the results obtained. 



Table XXVIII. — Effect of drugs on Nosema infection. 



Drag. 



Experiment 1. 



Experiment 2. 



Experiment 3. 



Experiment 4. , 



Propor- 

 tion. 



Results. 



Propor- 

 tion. 



Results. 



Propor- 

 tion. 



Results. 



Propor- 

 tion. 



Results. 



Betanaphthol 



Salol 



2:1,000 



2:1,000 

 2:1,000 

 3:1,000 

 3:1,000 

 5:1,000 

 10:1,000 



No infec- 

 tion. 



...do 



...do 



...do 



...do 



Infection. 

 ...do 



1:1,000 



1:1,000 

 1: 1,000 

 2:1,000 

 2:1,000 

 4:1,000 

 4:1,000 



No infec- 

 tion. 



...do 



...do 



...do 



...do 



Infection. 

 ...do 



1:2,000 



1:2,000 

 1:2,000 

 1:1,000 

 1:1,000 

 2:1,000 

 2:1,000 



No infec- 

 tion. 

 ...do 



Infection. 



...do 



...do 



...do 



...do 



1:5,000 



1:5,000 

 1:5,000 



Infection. 

 Do. 



Salicylic acid 



Carbolic acid 



Formic acid 



Eucalyptus 



Qiiinin 



Do. 







The results recorded in Table XXVIII show that the parasite was 

 destroyed by some of the drugs used but that it resisted others. 

 Their relative efficiency as indicated from these preliminary results 

 is shown by the arrangement in the table. Betanaphthol and salol 

 seem to be the most effective of those tried, and eucalyptus and 

 quinin the least efficient. 



Experiments were performed in which the inoculation with Nosema 

 apis was not followed by feedings with medicated sirup. The 

 results obtained show that under the conditions of the experiments 

 the drugs affected the parasite as seen by the lower percentage of 

 Nosema-infected bees in the colonies inoculated. In colonies re- 

 ceivuig subsequent feedings of medicated sirup a stiU lower percent- 

 age of infected bees was found. 



While it is thus estabhshed that Nosema apis is somewhat sus- 

 ceptible to the effects of some of the drugs, the experiments are 

 altogether too few for definite conclusions as to the extent of their 

 action. Statements regarding the effect of the drugs on Nosema- 

 disease, therefore, should be accepted cautiously, for the present at 

 least, unless they are supported by experimental or other good 

 evidence. 



1 In obtaining the desired proportion of the drug, betanaphthol, salol, salicylic acid, and eucalyptus were 

 dissolved ia alcohol. In the case of carbolic acid, formic acid, and the bisulphate of quinin aqueous 

 solutions of the drugs were employed. 



