PREFAOR, 9 
To entomologists who feel an interest in the causes of insect dis- 
eases and who wish to be able to judge with some satisfaction the 
work that has been and is being done on insect diseases this bulletin 
will be of special interest. It is believed that by the learning of the 
‘mistakes made by workers on bee diseases, and by the learning of 
the causes for such mistakes, the careful reader will be enabled to 
judge more accurately the value of the various reports that appear 
on the diseases of insects. 
THE AUTHORS. 
