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22nd January 1917 we observed dead bees being carried out. 

 February 23rd was sunny and warm ; the bees were active, and 

 large numbers flew on this date. During March the bees flew on 

 every fine day. Pollen gathering and cleaning up was in evidence. 

 ■ The stock continued normally throughout the spring and 

 summer, and it is clear that the driven bees added in November 

 did not contract the disease, although sick and healthy had been 

 in close association throughout the winter. 



The disease re-appeared in this stock in the following July. 



In addition to the foregoing experiment, four other cases of 

 stocks affected with the disease were united in the autumn with 

 lots of healthy bees. These healthy bees in each case covered from 

 five to six frames. In two instances the queens of the healthy 

 stocks were retained, and in the remaining two the queens of the 

 diseased stocks were left to head the combined colonies. All the 

 stocks were wintered with ample stores. In the following spring it 

 was found that two of these united stocks had succumbed, whilst 

 two survive. Of the survivors, one is headed by a healthy queen 

 and the other by a queen of a diseased stock. 



In another apiary nine stocks suffering from Isle of Wight 

 disease were strengthened by giving them driven bees in 

 September. The majority succumbed in December and January, 

 and only one remains alive. In these cases failure was not due to 

 shortage of healthy bees, as in each case the numbers used were 

 sufficient in themselves for wintering. 



In the following record further illustrations of the readiness 

 with which sick bees may communicate the disease to other bees 

 will be found, and also in some of the cases evidence that suscepti- 

 bility is not merely racial, i.e. that the bees are not suffering from 

 the disease in the first instance merely because they are all the 

 offspring of a particular queen. 



Results of Experiments in Re-Queening. — To a one frame lot 

 of bees, an Isle of Wight diseased remnant, a healthy queen 

 obtained from Wales with driven bees, which had wintered at 

 Aberdeen, was introduced upon the 28th March 1917. Honey was 

 fed from an Isle of Wight diseased stock, and the frames in the 

 hive (two) were both from Isle of Wight diseased stocks. 



Up till the 2nd of May, exactly five weeks, this lot continued 

 to exhibit symptoms of the disease, but after this date these 

 disappeared, and for four weeks the stock appeared perfectly 

 healthy. We regarded this as the period in which the old lot of 

 infected bees were gradually dying out, while meantime the young 

 bees of the new queen exhibited no signs of infection. 



On the 31st May two frames of bees from another stock were 

 added. From this time onward throughout the summer the stock 

 gradually increased in numbers, and at no time could it be said 

 positively that Isle of Wight disease was present. At the begin- 

 ning of August the strength had reached ten frames with brood on 

 eight. A rack of sections was placed on the frames. This month, 

 however, was very unfavourable to the bees, and on the 13th 

 crawlers were seen in front of the stock, and this was observed up 

 to the 4th September. This symptom passed off, and subsequent 



