CONTROL OF EUBOPEAN FOULBEOOD. 9 



work has shown, further, that the disease is caused by an organism * 

 which has never been found in any other brood disease of bees. The 

 cause of the disease is, therefore, a specific organism, and the disease 

 is entirely distinct from American foulbrood. This is an important 

 point, for there has in the past been considerable confusion in that 

 a few beekeepers have claimed that one disease changes to the other. 

 It should be made clear that this supposition is not supported by 

 any careful observation in the apiary, and that it was recognized 

 generally by beekeepers before the bacteriological investigations 

 were made that the diseases were distinct. 



(8) The organism causing European foulbrood does not seem from 

 observations in the apiary to be so difficult to eradicate as does the 

 one causing American foulbrood. This is partially confirmed by the 

 bacteriological observations also. 



(9) When a bee larva dies of European foulbrood the decaying 

 mass does not adhere closely to the cell wall at any time in the decay 

 or when it has dried down to a scale in the back or on the side walls of 

 the cell. Dead larvae may therefore be removed easily by the bees 

 if conditions are favorable for this cleaning. 



(10) The bees are able under suitable conditions of colony strength 

 and resistance to clean the cells so thoroughly that when future larvae 

 are reared in these cells the disease is not contracted. 



(11) The method of spread of the disease is not well known, al- 

 though there is some evidence that the infection is carried chiefly by 

 nurse bees. It has been observed that under some circurstances it may 

 be transmitted through feeding, but the experience of beekeepers indi- 

 cates that contaminated honey is not the common means of carrying 

 the disease. It is well known that honey from infected colonies may 

 be given to healthy colonies with entire safety provided the healthy 

 colonies are in such condition that they are able to resist the disease. 

 It is therefore not necessary to disinfect the honey from colonies 

 having European foulbrood, as is the case with that from colonies 

 suffering from American foulbrood. 



(12) It has not been found necessary to disinfect hives, combs, or 

 frames from diseased colonies. This does not indicate that the germ 

 causing the disease is absent from such material, but that if present 

 it does not do any damage. 



(13) While the disease spreads with great rapidity at times, it 

 does not seem to be so malignant as is American foulbrood, since 

 many colonies exposed to infection fail to contract the disease. 



These facts concerning the disease have been discovered in the 

 apiary rather than in the laboratory. The facts are supported by 

 repeated observations, and while the records of observation are not as 

 accurately made as are those of the laboratory the correctness of most 



^ Bacillus pluton. 



