DISEASES OF BEES 29 



Nosema and which consists in a conspicuous weakening of the 

 colony in spring, " spring dwindling," we believe to be the result 

 of a mixed infection of Nosema (in the middle intestine) and of 

 amoeba (in the malpighian tubes). It interested us very much to 

 learn that Amoeba has also been found in Great Britain by Dr. 

 Morison. 



Before I close my survey of Swiss experience with reference to 

 bee diseases, I should like to mention a special field of research 

 with which we have been busy for some years. It concerns the 

 the diseases of the queen. My colleague in Liebefeld, Mr. Fyg, 

 who devotes himself especially to this problem, tells me that up 

 to now, after an examination of about 500 queens, he has found 

 42 different abnormalities and diseases of the bee queen. We 

 believe that queen diseases play a far greater r61e in practice than 

 has hitherto been recognised. 



According to our views bee diseases are not only a question of 

 bad beekeeping methods and of bad environmental conditions. 

 We have seen many cases in which bee colonies, with the best of 

 care and imder the best environmental conditions, suffered heavily 

 from a brood disease or a disease of adult bees. Moreover, in the 

 history of apiculture we have seen that the alarm over bee diseases 

 did not originate with careless people and with bunglers, but on the 

 contrary with the pioneers of practical beekeeping. They had 

 realized that all their efforts to improve beekeeping were futile, as 

 long as the diseases were not scientifically studied and as long as 

 they were not conquered by special control methods. 



Ladies and Gentlemen, Switzerland is a small country and our 

 experience with bee diseases is based, therefore, only on relatively 

 little material. But I should like to point out that with regard to 

 climate, flora, beekeeping methods and races of bees we have 

 very varied conditions which perhaps invests our conclusions with 

 somewhat greater value. We are always very eager to learn the 

 experience of other countries. Therefore I should like to take the 

 liberty here, as I have done at former international congresses of 

 apiculture, of pointing out the desirability of statistics on the 

 occurrence of bee diseases in all lands. We were highly interested 

 in the work which Mr. Morland has undertaken in determining 

 the geographical distribution of foul brood in England.* I can show 

 you here with the aid of maps the distribution of the four most 

 important diseases in Switzerland.! We should be much better 

 informed on many questions of bee pathology if we possessed such 

 maps of all countries. 



If, in conclusion, I should give the reason why Switzerland shows 

 some successes in controlling bee diseases I believe I can say that 



• " Brood Diseases of Bees," Rothamsted Experimpntal Station 

 Conference Report 18, 1934. (Out of print in separate copies). 



f Maps showing the distribution of American foul brood, European fouj 

 brood, Acarine disease and Amoeba disease in Switzerland were exhibited. 



