30 



In these cases as well as in the case reporled by Wolfram (26) 

 Aspergillus flavus was found to be the cause of the disease. So far 

 it has not been repor ted from Sweden, probably 011 account of in- 

 sufficient knowledge in the matte r of bee-diseases among most of 

 our practical bee-keepers. There is no doubt that upon close inquiry 

 additional species of the genus Aspergillus will be found to cause 

 mycosis in bees just as in the case of mycosis in man. (The literature 

 on this latter subject may be found in T öresson 24). Aspergillus 

 fumigatus, the most dreadful among the species causing mycosis in 

 man and higher animals, has been found to attack insect larvae as 

 reporled by Gee and Massey (9). It is further of interest to note, 

 that Aspergillus nidulans, another pathogenic mould, was originally 

 found in a bumble bee s nest (Eidam 7). 



Another kind of mycosis is the one caused by Pericystis aluei, in 

 appearance similar to aspergillosis. It was originally described by 

 Betts (5) but the disease has låter also been observed in Germany. 

 (Maaszen, according to Bahr.) 



Totally different from these diseases is the one herein reported 

 known as bee-paralysis and due to the toxin-producing properties 

 of moulds growing in the hive. The frequency of moulds in the 

 bee-hive has been referred to in the above. Also Maaszen finds 

 moulds to be common in hives, and White (25) remarks (pag. 25): 

 »A large number of common fungi were found in the flora of the 

 intestines and in cultures from the pollen and the combs. » 



In order to test the condition of growth of bee-hive fungi a series 

 of cultural experiments were made with PeniciUium sp. and P. 

 stoloniferum. The results of the experiments are given below. 



No growth takes place in pure wax. Fine growth was found to 

 take place on old combs. As is well known, the chitinous cocoons 

 remain in the cells when the bees are hatched. Possibly other 

 waste-products as well combine to make old combs free from honey 

 such excellent media for moulds. Fine growth was further obtained 

 on pollen collected from honey-combs, sterilized and put in test 

 tubes. Almost any mould will grow on flour. To feed bees on 

 flour as a substitute for pollen is, therefore, inadvisable from this 

 standpoint as well. Unsealed brood, killed in the autoclave and 

 inoculated with PeniciUium sp. and P. stoloniferum became completely 

 enveloped with a coating of the fungi. As to the susceptibility of 

 sealed brood cells nothing can be said for certain, but such combs are 

 sometimes found to be mouldy. The brood cells are capped with 



