62 HISTORICAL NOTES ON BEE DISEASES. 



bees. In the feeding experiments of this year some of the brood 

 died. This slight difference in the results, from those obtained the 

 preceding year, was probably due to the difference m the details of 

 the experiment. Although some of the brood was found dead, the 

 condition did not present sufficient symptoms, in the opinion of the 

 author, to justify him in pronouncing it foul brood. Many punctured 

 cappings were observed and dead larvae of a dull color were present. 

 These dead larvae were found by cultures to contain Bacillus alvei. 

 The death of these larvae might have resulted from chiUing or other 

 causes, and the cappings may be punctured by the bees m different 

 conditions that result in the death of the brood after capping. 



The presence of Bacillus alvei could easily be explained from the 

 fact that cultures can be isolated from apparently healthy larvae 

 taken from a colony to which the spores of the species has been fed. 

 There was also wanting in these dead larvae the yellowish color 

 usually observed in those affected with European foul brood. The 

 slightly viscid character which is sometimes present in brood dead of 

 European foul brood was also absent. The rapidity with which the 

 condition disappeared when the days became warmer was another 

 indication that the disease was not European foul brood. The 

 results of the experimental inoculation of healthy brood with cultures 

 of Bacillus alvei were negative, and were therefore similar in this 

 respect to those of the preceding year. 



Since a number of articles had appeared about that time advo- 

 cating the use of formaldehyde gas in foul-brood treatment, some 

 preliminary experiments were conducted to test the efficiency of 

 this disinfectant when applied to brood combs. The experiments 

 demonstrated that it is not easy to destroy the spores which are 

 within the dead larvae and that the gas as it was being applied in the 

 treatment of the brood diseases could not be relied upon. 



The samples of American foul brood which were received for 

 examination in 1902 were labeled ''foul brood" when received. 

 From the time Cheshire and Cheyne published their joint paper in 

 1885 to 1902 Bacillus alvei was suspected as being the cause of "foul 

 brood." Bacillus alvei, however, was not encountered in the samples 

 labeled "foul brood" received and studied in 1902 (p. 60). Spores 

 were found present in the deca3dng remains of the dead brood, but 

 they refused to germinate on artificial media. 



The fu'st time that these spores were caused to germinate under 

 laboratory conditions was in 1903. For this purpose a special agar 

 medium was used, made from the larvae of bees. A somewhat similar 

 medium had been used by Lambotte (p. 55), but with it he did not 

 obtain a germination of these spores. This special agar was used 

 in a test tube, and Liborius's method for making inoculations was 



