14 Circular 218, U. S. Dept. of Agriculture. 



desirable to eliminate bees dying from exhaustion, and Mrs. Pixell- 

 Goodrieh (15) has worked out methods for the determination of 

 death from old age. It is out of the question to submit all the 

 samples received by the Bureau of Entomology to the tests which 

 she has described, but there can be no question that death from 

 quite natural causes induced by poor care is often mistaken by 

 beekeepers for the work of some disease. 



Even though we eliminate the cases where there is reason to sus- 

 pect poor care as the cause of death of adult bees, there still remain 

 cases where evidence exists that death is due to some disease which 

 can not be diagnosed in the laboratory at present. Cases which 

 answer to the usual description of the so-called bee paralysis can 

 not be diagnosed in the laboratory because there is still doubt as 

 to the cause or causes of the trouble. According to Turesson (20) 

 this disease is due to the molds which bees sometimes get in their 

 food under unsatisfactory conditions in the hive, such as those of 

 damp hives in winter. Whether there is more than one condition 

 which is put under this name by beekeepers is still a matter of doubt 

 (H). Other names have been given by beekeepers to abnormal 

 death of adult bees, among which may be mentioned May disease 

 (rarely used in the United States) and disappearing disease. The 

 multiplication of names without adequate descriptions of symp- 

 toms or some other means of differentiating the disease has nothing; 

 to commend it, and beekeepers will do well to avoid the making of 

 new and confusing names for adult bee diseases. 



A serious difficulty arises from the fact that the symptoms ob- 

 served for almost all the conditions which cause the abnormal 

 death of adult bees are much alike. Even for Xosema disease, the 

 cause of which is known, there is no definite description of symp- 

 toms, and this is likewise to a considerable degree true of the Isle 

 of Wight disease. Abnormal bees behave much alike, whatever 

 the cause of the abnormality, and the descriptions of characteristic 

 symptoms for the several diseases is exceedingly difficult. Symp- 

 toms of adult bee diseases can not be described from the appearance 

 of the dead bees, as is the case with the brood diseases. 



