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disease. On the 4th of August the stock swarmed, and the swarm 

 was successfully hived. Up till the 20th of the month the queen 

 with the parent colony had not begun to lay, and upon the loth 

 September this stock was found to be broodless. On this date the 

 swarm of 4th August was placed on top of parent stock, each with 

 its own queen. The two boxes were separated by excluder. On 

 the 25 th September the strength was ascertained to be clustered 

 on eight frames in the parent stock, and on five in the swarm. 



During the whole course of this experiment, lasting over a 

 period of three months, from the introduction of the experimental 

 queen until the bees were wintered, no traces of disease were ever 

 observed. The stock was found in January to have numerous 

 dead. There were signs of dysentery upon the frames, and the 

 colony died out in February. 



Experiment No. 6. — This nucleus consisted on the i8th of March 

 19 1 8 of five frames of bees with brood upon two. On the 20th 

 a queen surviving from an Isle of Wight diseased stock was intro- 

 duced. The stock progressed normally throughout the summer, 

 and at the beginning of July was of full strength, having brood on 

 nine frames. On the 7th July a large swarm came off. The queen 

 cells in the parent stock were destroyed and the queen of the 

 swarm was returned. The stock continued to build up, and at the 

 beginning of September, although it had yielded no surplus stores, 

 was large and healthy, with sufficient stores for wintering. At no 

 period of its history have any signs of disease been observed. 



In the beginning of March 1919 this stock was found to have 

 wintered successfully. 



Experiment No. 7. — On 4th May 1918 a nucleus consisting of 

 two frames of healthy bees having two small patches of brood was 

 given a queen of above named history which survived from a stock 

 of Isle of Wight diseased bees. The queen was an old one, and on 

 7th June was withdrawn from this stock, which at this date covered 

 three frames, and was replaced on the nth by a younger (19 17) 

 queen of similar history. The stock progressed with no visible 

 signs of disease until upon the 17th July it covered eight frames 

 and had brood upon six. From this date onward until the begin- 

 ning of September the strength remained stationary. The amount 

 of sealed stores was moderate, and the stock required feeding 

 before winter. No sign of Isle of Wight disease was ever 

 observed in this stock. 



In the beginning of March this stock was found to have 

 wintered successfully. 



Communication of the Disease. — As recorded above, attempts 

 to convey the disease by combs and stores have in general been 

 failures, while contact experiments of presumed healthy with sick 

 bees have yielded a proportion of positive results. We incline 

 strongly to the view that the sick worker bee is the chief agent in 

 communicating the disease to other bees. 



Notwithstanding the variation in the result as shown in the 

 other experiments, the evidence as a whole derived from a very 

 wide experience in dealing with the disease in the North of 



