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The Connection of Nosema apis with Isle of Wight Disease in 

 Hive Bees. Remarks on the evidence submitted in the 

 Board of Agriculture Reports of 1912 and 1913. By John 

 Anderson, M. A., B.Sc, Lecturer in Bee-keeping to the North of Scotland 

 College of Agriculture. 



(Read 24th January 1916. MS. received 5th February 1918.) 



I. Historical and Introductoky. 



Isle of Wight Bee Disease was reported from the island after which it is 

 named in the year 1904, and it was at first stated that it did not appear on 

 the mainland till 1909. It is now, however, believed that "the trouble 

 was not unknown on the mainland prior to the Isle of Wight outbreak." ^ 



It was in 1906 that bee-keepers became really alarmed, and Mr A. D. 

 Imms, B.A., M.Sc., was requested by the Board of Agriculture to proceed 

 to the Isle of Wight to investigate. He found the disease prevalent over 

 practically the whole of the Island, and he collected much information from 

 the bee-keepers as to the symptoms and course of the disease, the ways in 

 which they believed that infection was conveyed, and the remedies they 

 had experimented with. He dissected a number of bees, and made smears 

 of the gut contents, fixing and searching these for bacteria. 



Imms' description of the symptoms is as follows : " The earliest noticeable 

 symptom of the disease is the inability of the affected bees to fly more than 

 a few yards without alighting. As the disease progresses the bees can only 

 fly a few feet from the hive, and then drop and crawl about aimlessly over 

 the ground. They are often to be seen crawling up grass stems, or up the 

 supports of the hive, where they remain until they fall back to the earth 

 from sheer weakness, and soon afterwards die. In a badly infected stock 

 great numbers of bees are to be seen crawling over the ground in front of 

 the hive, frequently massed together in little clusters, while others remain 

 on the alighting board. . . . Affected stocks examined in early spring show 

 symptoms similar to those of dysentery. The bees discharge their excrement 

 over the combs and on the sides, floor, and alighting board of the hive. . . . 

 The bee-keepers state that this condition is only present after the winter 

 confinement within the hive. . . . After the winter is over and the bees 

 are all on the wing, no dysentery is noticeable, and all the diseased bees 

 that have been dissected showed the opposite condition of distension of the 

 gut. . . . The colon and adjacent part of the rectum are enormously distended 



' Board of Agriculture Report, 1912, p. 13. 



{Reprinted from the "Proceedings of the Royal Physical Society," Vol. xx., pp. 16-2S.] 



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