362 



Scientific Proceedings^ Royal Dublin Society. 



after some weeks. In the graph in the text figure the Yadil-treated hive is 

 shown in a wavy line. It was 100 per cent, infected at the end of September 

 and the beginning of October. By the middle of October the infection had 

 gone down to about 40 per cent., this probably being due to the hatching out 

 of new bees. Despite the treatment infection steadily crept up, and the stock 

 ultimately died out before the end of the year 1923. Possibly the Yadil was 

 not strong enough, but this was the strength (2^ per cent.) sent by the makers. 

 In the case of the two hives treated with Succus Allii, we had more 



encouraging results. One stock marl^ed thus in the figure, began at 



10 per cent, infection, which remained fairly uniform till December when it 

 rose suddenly, but thereafter fell till all the samples of bees examined were 

 negative. This stock is still negative, and healthy. 



/=***»'. 'S-uJC 



Ql^rttA 



^"^---^ 



. . . _ ,oUi*L v**^ 



. - S^oouo^ cJL^ Jo-'^Z 



Graph showing percentages of infection of three liives treated respectively with Yadil, 

 Succus Allii, and Succus Allii followed by tar, for four months of the year. 



The other hive marked -•-•-, gave much the same results, but in this case, 

 Stockliolm tar candy was given at the end of December; the stock died out 

 about the end of January, poisoned, we believe, by the Stockliolm tar. Never- 

 theless, we consider that if the tar had not been given, there would have been 

 some ground for believing that this stock might have been cured. 



In the other case where Yadil was given the percentage of infection at the 

 beginning of the experiment was only about 10 per cent., and never rose above 

 50 per cent., but this stock was the first to die out. 



These results, meagre as they are, nevertheless lead us to believe that an 

 efficient treatment of Acarine or Isle of Wight disease might be found along 

 these lines. 



Garlic can easily be grown by bee-keepers, the bulbs can be dug up, and 

 the juice expressed and mixed up to a strength of 15 per cent, with sugar. 



