A. HISTORICAL NOTES ON BEE DISEASES. 
Baur, 1906. 
Another publication by Bahr! appeared in 1906, in which he gives 
the results obtained from his further investigations. He reports that 
more than 200 cases of foul brood had been examined. The following 
points are noted in Bahr’s paper: 
1. One can not be sure with what disease he was working. 
2. He does not always find Bacillus alvei in foul brood. 
3. With cultures of Bacillus alvei he was not able to produce foul 
brood either by spraying the larve or by feeding cultures of the 
bacillus. He failed also to produce the disease by using the contents 
of the dead larvee for spraying or as food in sugar sirup. 
4. He suggests that the reason for these negative results may be 
either that Bacillus alvei is not the cause of foul brood or that the 
proper time or manner in which such infection can be produced 
experimentally had not been discovered. 
5. He did not find any other bacillus as a possible cause of the 
disorder. Bacillus alvet was not found in the eggs or in the sexual 
organs of the queen, as had been reported by Cheshire (p. 21), Har- 
rison (p. 49), and others. 
6. He suggests that possibly the cause of the disease is an ultra- 
visible virus and that possibly the disease is transmitted through the 
queen. 
Tt appears likely that Bahr was working with European foul brood, 
but this is not at present positively known. If he studied American 
foul brood, he must have overlooked the fact that there are numerous 
spores (Bacillus larve) present in the decaying remains of the larve 
which do not grow on the artificial media commonly used. In sup- 
port of his theory that the disease is transmitted by the queen he 
says thau he has introduced a queen from a diseased colony into a 
healthy one and produced foul brood as soon as the queen could lay 
the eggs, and that he has introduced queens from healthy colonies 
into apparently doomed ones with the result that the diseased colonies 
quickly recovered. 
These experiments should be repeated for a confirmation of the 
results. If, as is probable, Bahr worked with European foul brood, 
there were probably other factors present which were not accounted 
for. His failure to find Bacillus alvei in all the samples examined 
is interesting, and his failure to produce foul brood with cultures 
of Bacillus alver repeats the experience of some others. 
l Bahr, L., 1906. Om Aarsagen til Bipesten og dennes Bekseempelse. Foredrag holdt ved DBF’s Dis- 
kussionsm¢de d. 2 Septbr. 1906 i Esbjerg. Sertryk af Tidsskrift for Biavl. Nr. 17. 
