14 HISTORICAL NOTES ON BEE DISEASES. 



brood or European foul brood. The other form of the disease, in 

 which the brood was supposed to be placed with the head directed 

 inward, most probably was not an infectious disease. In the treat- 

 ment of foul brood Schirach recommends the removal of all combs 

 from the bees. This principle is the one upon which is based the 

 methods which are most successful at the present time in the treat- 

 ment of the infectious brood diseases. 



The other abnormalities in the colony which are mentioned in 

 the paper relate to the condition of the queen. These are conditions 

 familiar to the bee keeper, but which may occur more often when an 

 infectious brood disease is present. Mention is also made of the fact 

 that brood is sometimes killed by chilling. Schirach refers to this 

 as an accident and not as a disease. 



Leuckart, November 12, 1860. 



Leuckart ^ had entertained the opinion that infectious foul brood 

 was due to a fungus, and he felt that his view was strengthened by 

 some work which was done on the diseases of the silkworm. During 

 the summer of 1860, however, he had an opportunity to see much 

 infectious foul brood in samples of comb and in colonies. In the 

 diseased material he found no fungi that he could not attribute to 

 the phenomenon of decay. He states in the paper that foul brood 

 is obviously a collective name that includes various forms of disease 

 with the features in common of being epidemic, attacking early 

 stages, and being usually fatal. One sample was examined, and a 

 number of diseased and dead larvae was found to contain an uniden- 

 tified fungus. The majorit}-^ of them, however, did not contain the 

 fungus; yet these latter larvse were thought to be dying of the usual 

 type of foul brood. From his summers' experiences Leuckart ar- 

 rived at the conclusion that the infectious foul brood was not due to 

 a fungus. 



MoLITOR-MtJHLFELD, ApRIL 15, 1868. 



Molitor-Miihlfeld ^ in 1868 reported some starthng observations 

 relative to the cause of foul brood. He writes that foid brood is of 

 two kinds, the mild kind and the so-called infectious or virulent one. 

 The mild form of foul brood, according to his views, resulted from a 

 chilling of the brood. During the early warm days of spring, he 

 argues, brood rearing is stimulated to such an extent that when 

 colder weather follows it is impossible for the bees to care for all the 

 brood, and as a result the neglected brood is chilled, dies, and be- 



1 Leuckart, Dr., November 12, 1860. Zur Naturgeschichte der Bienen. 3. Zur Kenntniss der Faul- 

 bnit und der Pilzkrankheiten bei den Bienen. Eichstadt Bienenzeilung, 16 Jahrg., Nro. 20, pp. 232-233. 



2 Molitor-Miihlfeld, April 15, 1868. Die Faulbrut, ilire Entstehung, Fortpflanzung und Heilung. Eich- 

 stadt Bienenzeitung, 24 Jahrg., Nro. 8, pp. 93-97. 



