158 



From the foregoing it would appear that Nosema is readily 

 communicable to the bees by an infected queen. It cannot be said 

 with certainty that the death of the queen under the conditions of 

 this experiment was due to infection with the parasite. 



Experiment III. On the 9th October a queen was isolated and 

 observed to feed upon candy contaminated with fresh Nosema 

 spores. She was then caged with a number of her own bees with a 

 view to their removing any contamination which may have taken 

 place from the surface of her body. 



After twenty hours she was again isolated and transferred to a 

 freshly sterilised cage containing clean candy along with a small 

 number of bees taken from a tested Nosema free stock. 



On the 1 2th one bee was removed from the cage and the chyle 

 stomach examined. Only one or two free spores were observed. 

 These we assume were ingested forms. 



On the 17th a newly dead bee was examined and a few large 

 meronts were seen. 



On the 22nd one live bee was taken and on examination found 

 negative as regards Nosema. 



On the 25th two bees were killed and examined ; in one stray 

 spores were seen but no developing stages. In the other the 

 spores were more numerous, but again infected cells were not 

 observed. 



On the evening of this date the queen died. She was examined 

 on the morning of the 26th, and a very heavy infection with 

 Nosema was found to have been established. Four attendant bees 

 remained, and these were examined with the following results — two 

 contained scattered spores and intracellular stages, and in the other 

 two meronts only were observed. 



The infection in these four bees was of a comparatively slight 

 character and in marked contrast to the condition in the queen. 



From the result of the foregoing experiments there seems little 

 doubt that an infected queen under normal conditions will probably 

 be as certain an agent of infection as can exist. Further, the 

 mortality amongst Nosema infected queens in our experiments 

 has been significantly high. 



Altogether, we feel justified in concluding that in any stock 

 harbouring Nosema, there is considerable probability that the 

 queen will sooner or later become infected with this parasite. 

 When this happens, in view of the personal hygienic relations 

 existing between queen and attendant workers, she becomes 

 a centre of infection, and we may expect the disease to make 

 rapid progress. In this connection it may, theiefore, be poinied 

 out that an obvious remedial measure, where the presence of 

 Nosema is known or even suspected, is to effect a change of 

 queen. 



Probably, where the circumstances admit of it, the stock might 

 be left queenless for a time. The significance of a queenless period 

 is that it permits of the dying out of infected bees, and thus 

 increases the possibility of final elimination of the parasite from the 

 stock. 



