149 



parasitized, all the cells seemed full of spores, the colon was practi- 

 cally empty. 



On the 28th five live bees were taken leaving the hive, the chyle 

 stomach was whitish in all. Spores were found in four ; one 

 showed early stages of the parasite. The stock was working well 

 all day. There were no "crawlers" and no signs of Isle-of-Wight 

 disease. 



During June the weather was mostly favourable and the stock 

 increased to nine frames of bees, but stores were not very plentiful. 

 Microsporidiosis appeared to be on the decrease, but foul brood 

 was suspected on the 8th. 



In the beginning of July the stock had increased to ten frames 

 and a super was put on. 



Microsporidiosis was not marked, although very numerous spores 

 were found in one bee examined. Experiments with this bee 

 yielded results rich in Nosetna infection. No difficulty was 

 experienced in maintaining bees alive until the spore stage was 

 reached. 



The stock, although as noted was not showing any very marked 

 signs of trouble, did not increase, but probably diminished in 

 numbers in succeeding weeks, although the queen continued to lay. 

 On the older frames the presence of sac brood, which was suspected 

 on the 8th, was definitely confirmed and found to have increased 

 in amount. 



Throughout the period that Nosemav/a.s being readily found in a 

 very high proportion of the bees, there were none of the char- 

 acteristic signs of Isle-of-Wight disease, and no observer of the stock 

 familiar with this condition could possibly have diagnosed it as 

 present. Nothing to suggest it had been seen since the previous 

 October. It was, however, obvious that the combined presence of 

 Nosetna and sac brood disease was adversely affecting the stock. 

 About the middle of July the first signs of Isle-of-Wight disease 

 made their appearance. There was an inclination in bright sun- 

 shine to crowd in fair numbers on the alighting board, and 

 especially to crowd in large numbers on top of the frames rather 

 than to fly when the hive was opened. Also a limited number of 

 bees when opened were found to have the colons congested and the 

 chyle stomach contents purplish in colour. Further, the number of 

 bees leaving and enterin<^ the hive in working hours and in suitable 

 weather was relatively small in proportion to the size of the stock, 

 and to those working from adjacent hives even where these stocks 

 were smaller. At this date, 20th July, the stock was markedly 

 short of stores. 



In order to combat the sac brood two of the worst frames with 

 bees upon them were removed to a small hive, and two frames of 

 foundation were placed in the middle of the brood nest. Syrup 

 was fed Eighteen loiterers were picked off the alighting board, 

 and of these only three showed " Isle-of-Wight " disease, intestinal 

 symptoms ; the others appeared normal. Two bees examined in 

 detail showed no trace oi Nosema, and it may be added here that 

 Nosema, although repeatedly looked for, was not again found in this 

 stock. 



In the beginning of August sac brood was still present and the 



