The Isle of Wight Bee Disease. 65 



received from five different counties in tlie south of England. 

 They were also able to demonstrate by experiment that the 

 organism was pathogenic for bees. Dr. Zander, working inde- 

 pendently at Erlangen, in Germany, also found a minute 

 organism in the alimentary canal of diseased bees, to which he 

 gave the name of Nosema apis (Zander, 1909). This has been 

 subsequently proved to be the same parasite as was discovered 

 by Fantham and Porter. The latter observers have given a 

 very full account of the organism, published in the Zoological 

 Society's Proceedings (Fantham and Porter, 1911), and also in 

 the Reports issued by the Board of Agriculture in 1912 and 

 1913. 



Nosema apis has been found in almost every stock appar- 

 ently infected with the Isle of Wight disease, and there is, 

 therefore, every reason to regard it as the primary agent 

 responsible for the complaint. This conclusion is further 

 supported by the fact that no other organism has been detected 

 that can be accused of causing the infection. Several 

 authorities claim that microscopic examination of infected bees 

 for the presence of Nosema is necessary for definitely diagno- 

 sing the disease, the general symptoms not being regarded by 

 them as being sufficiently reliable. A microbe. Bacillus 

 pesti/ormis apis, was found by Maiden in diseased stocks, but 

 is by no means constantly present, and cannot, therefore, be 

 regarded as the pathogenic agent. If it has any connection 

 with the disease, it is of a secondary nature. 



Distribution of the Disease and its Parasite. 



It may be said that the disease is prevalent over the greater 

 part of England and Scotland, and it is principally owing to 

 its severity in the Isle of Wight that attention has been 

 focussed on to it in that locality. Abroad it is known to occur in 

 Germany, Switzerland, and America, and the Nosema definitely 

 found to be present in each instance. In Australia, Tasmania, 

 and Canada, Nosema has also been detected, but apparently 

 without causing loss to the bee-keei)ers. With the growth of 

 knowledge of bee diseases, it is probable that the Isle of Wight 

 complaint will be found to occur in a number of other 

 countries where it has not up to the present been recognised. 



Position of Nosema apis in the Animal Kingdom, 

 AND its Life History. 



Nosema apis belongs to the Protozoa, which are one-celled 

 animals ; it has therefore no relationship with bacteria, which 

 are placed in the vegetable kingdom. Many Protozoa are known 

 to cause various diseases, of which malaria and sleeping sick- 

 ness are well-known instances. An allied species of the same 



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