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carrying such mites upon, their body move about in 

 the cluster — rubbing shoulders, as it were with their 

 healthy fellows— the mites are transferred from bee to 

 bee. When this has happened, the adult females 

 instinctively find their way to one or other of the first 

 pair of thoracic air openings which they enter. Fertili- 

 sation has taken place previously in the bee, from which 

 the mite migrated, and on the arrival in the new bee- 

 host, egg-laying commences very usually, but not in- 

 variably, near the entrance to the tube. In due course, 

 brood in all stages, from eggs to adults, are to be 

 encountered right along the tracheal system of this 

 part of the body as far as the diameter of the tube 

 will permit the mites to pass. Fully developed mites 

 pair within the bee and after fertilization migration 

 takes place, although it seems to be the case that some 

 females do not migrate, but lay eggs within the bee in 

 which they themselves were bred. 



The Queen in Relation to the Disease. 



An important factor in the spread of Tarsonemus 

 infestation within a hive-bee colony which calls for 

 special mention is the queen. 



I have found that nearly 50 per cent, of queens head- 

 ing Acarine infested stocks, are themselves affected 

 with the parasite. 



The dangers from an infested queen are two-fold. 

 The queen does not usually succumb to the disease 

 during the life of the colony, and if infested early she 

 may therefore remain a centre of dissemination of the 

 parasite over a prolonged period. Secondly she is in a 

 progressively weakened condition which directly affects 

 both the rate of her production of bees and probably 

 also the stamina of her brood. 



The survival of the queen even when affected with 

 the disease is a feature which has puzzled observers. 

 It may be pointed out that the mortality which is 

 associated with infestation results largely from the 

 infested workers leaving the hive, and their being un- 

 able to return, owing to weakness and cold. If it were 

 the habit of the queen to leave the hive (apart from her 

 nuptial flight, at which stage she has had little oppor- 



