8 HISTORICAL NOTES ON BEE DISEASES. 



The writings of all these men should be read. If an investigator 

 has done work on the causes of other diseases than bee diseases, but 

 chooses to write on bee diseases, the reader will usually profit by 

 reading his papers. The great mass of literature, on the other 

 hand, created by those who have not worked on the cause of any 

 disease can as a rule with profit be rejected. 



Having determined whose papers should be read, the character 

 of the work of each investigator should be carefully noted. If the 

 character of a man's work proves to be good, give weight to all his 

 statements, but if the character of a man's work is poor, expect 

 untrue statements and erroneous conclusions. If one will learn in 

 this way to judge the different papers, one will soon know what to 

 believe and what to suspect, but if one does not learn to do this he 

 will be forever at the mercy of printed pages. 



As the reader forms his opinion of the character of the work done 

 by the different men referred to in this bulletin, permit the sugges- 

 tion that he exercise some leniency inasmuch as the time at which 

 a man works and the circumstances under which he labors are 

 frequently in a measure responsible for mistakes. The reader will 

 note, however, that many times the mistakes made in the study ot 

 bee diseases have been made only because insufficient and careless 

 work was done by the investigator. In such cases no leniency is to 

 be exercised in arriving at conclusions. 



The writers of this bulletin have commented very little on the 

 character of the work done by the different authors of the papers 

 reviewed. The views of these men as they are found in the papers 

 are given and the reader is allowed and urged to judge for himself 

 whether or not such views are true. To aid the reader, however, 

 the writers have made a few suggestions when it was thought that 

 they might prove advantageous. The page references refer to pages 

 in this bulletin. 



In reading a paper there is always the danger of misinterpreting 

 an author's conception. This danger is greatly increased if the 

 author of the paper criticized uses a foreign language. Realizing 

 this possible source of error, we have endeavored in every case to be 

 cautious. When quotations from papers written in a foreign lan- 

 guage were selected, rather free translations of them into English 

 have been made. 



We disagree with a very large number of the statements which 

 have been made by different authors referred to in this bulletin con- 

 cerning the causes of bee diseases. Therefore let it be emphasized 

 that the reviews which are here made are intended to express the 

 opinion of the author of the paper reviewed, and not by any means 

 the opinion of the writers of this bulletin. 



