April, '08] JOURNAL OP ECONOMIC ENTOMOLOGY 103 



dertaking, but the other impediment will effectually prevent advance- 

 ment unless handled vigorously. 



There are now recognized two diseases of the brood which are in- 

 fectious in their character : These are designated American foul 

 brood and European foul brood. While they differ in their cause 

 and symptoms, their ultimate effect is similar. The brood succumbs 

 to the disease and the colony dwindles from a lack of young bees to 

 replace the old workers, which die of old age. Finally the colony is 

 entirely destroyed. It is now definitely determined that American 

 foul brood is caused by a specific micro-organism. Bacillus larvae, 

 and probably European foul brood is caused by some other micro- 

 organism, since it is equally infectious and spreads in the same 

 manner. 



When a colony dies from disease, bees from another colony rob 

 the 'hive and thus carry infection to their own hive. Disease may also 

 be spread by feeding a colony honey which has been extracted from 

 a hive containing disease and by introducing queens which come in 

 cages containing candy made with infected honey. 



The investigation of the causes of these diseases has attracted the 

 attention of scientists for many years. In Europe, at present, there 

 are several bacteriologists at work on the subject and it is also one of 

 the lines of work now being pursued in the agricultural investiga- 

 tions of the Bureau of Entomology. The work so far done indicates 

 that the problem is by no means an easy one and that it should be in- 

 vestigated by well trained men. The work has, in fact, suffered from 

 the publications and statements of untrained men, and it is to be 

 hoped that in the future it will not be necessary to spend more time 

 pointing out the mistakes in immature work. 



The control of these two diseases is the great economic problem now 

 confronting those interested in this industry. The present approved 

 method of treatment for both diseases consists of the removing of all 

 infected material from the colony and in compelling the bees to build 

 new, clean combs. Perhaps, when the characteristics of the causal 

 micro-organisms are better known, it may be possible to devise meth- 

 ods for the use of disinfectants or drugs to save the comb, but until 

 more information is available, the use of drugs, either for feeding or 

 for fumigation, cannot be advised. Several attempts have been made 

 to save the combs by fumigation with formalin, but this is only ex- 

 perimenting in the dark, and it is safe to recommend only such meth- 

 ods as are known to be effective. 



While it is possible for any bee keeper to eradicate either disease 

 from his apiary, it is difficult to get all bee keepers to do it ; and care- 



