42 DISEASES OF BEES 



jet-black in appearance. After about ten to twenty days all the 

 diseased bees present in a colony seem to die suddenly, or, perhaps, 

 are killed off by the healthy members. They invariably perish 

 suddenly and their dead bodies are found lying outside the hive. 

 But bees that die of this malady do not give off any perceptible 

 odour. 



There is a form of paralysis, that is quite distinct from the one 

 first mentioned, which at times causes serious depletion in the 

 strength of colonies. The symptoms of this malady resemble 

 acarine disease in that the affected bees are deprived of the use of 

 their wings. Bees suffering from this kind of paralysis appear to 

 be normal in every respect except that their wings are paralysed 

 and often also dislocated. The disabled bees, mostly young ones, 

 leave and run away from their home and eventually die of exhaus- 

 tion. They do not form clusters on the ground as in the case of 

 Acarine. The malady comes on suddenly, generally early in July, 

 and again vanishes after a week or ten days. This form of paralysis 

 is no doubt identical to the " Disappearing Disease " that at one 

 time caused such serious losses to many apiarists in the U.S.A. 



With the exception of the malignant paralysis all the other 

 diseases mentioned are of transitory duration and affected colonies 

 recover without the application of any remedial measures. 



Dr. Tare (Rothamsted). It is by no means certain that Bee 

 Paralysis is a single disease, and, as can be seen from Brother 

 Adam's remarks, there is some confusion as to exactly what is 

 implied by this term. Whether such diseases as Waldtrachtkrank- 

 heit. Bee Paralysis and Black Robber Disease (Black shiny bees) 

 are distinct complaints cannot be stated with certainty until their 

 causes have been definitely determined. At present there is no 

 accurate diagnostic feature by which these diseases can be dis- 

 tinguished, though the work accomplished by Dr. Morison may 

 provide a useful clue. It may transpire that there are several virus 

 diseases of the adult bee which differ slightly from one another, or 

 that there is a single disease modified by the presence of various 

 bacteria. Until practical experiments have been made, any state- 

 ments regarding the etiology of these diseases can only be specula- 

 tive. In this connection it is of interest that Dr. Morison states that 

 Dr. Phillips, of Ithaca, believes that American Bee Paralysis is not 

 identical with the disease occurring in this country. Many bee- 

 keepers state that Black Robber Disease or Bee Paralysis can be 

 cured by requeening the affected colony. However, the success of 

 this method cannot be considered as proven, and the reason for it 

 is not known because there is, as yet, no definite indication that 

 the queen carries the disease. 



In 1933, Burnside, working in the United States, published a 

 paper entitled " Preliminary Observations on Paralysis of Honey- 

 bees." He concluded that the disease is mildly infectious, and often 



