20 HISTORICAL NOTES ON BEE DISEASES. 



Chesliire, believing that foul brood was due .to a bacillus and not 

 to a micrococcus, as claimed by Schonfeld, sought to demonstrate the 

 fact by repeating the inoculation experiments of the latter, using the 

 larvae of the blowfly used by Schonfeld (Musca) Calliphora vomitoria. 

 Sixty blowfly larvae were divided into three equal groups: 20 were 

 not brought near foul-brood material; 20 were inoculated with the 

 bacillus in the vegetative form ; and 20 with the spores of the bacillus 

 contained in the coffee-colored foul-brood material. IMicroscopic 

 examination at the end of 24 and 48 hours failed to give evidence of 

 disease in the fly larvae. After 72 hours, however, active bacilli were 

 observed. Cheshire writes, "This is most completely confirmatory 

 of my position; but how could it be reconciled with Schonf eld's 

 assertion, that he found the dead flies full of micrococci? Had he 

 searched further, he would have discovered that dead blowflies are 

 generally full of micrococci." In demonstrating this error of Schon- 

 feld, he unfortunately made an error quite as great himself. 



Cheshire attempted to obtain, by cultures, proof to support his 

 contentions concerning the etiology of foul brood. He prepared a 

 medium by taking drone larvee and expressing and straining their 

 juices into two test tubes. Tube No. 1 was inoculated with a small 

 quantity of coffee-colored material, which for the most part contained 

 only spores; tube No. 2 was inoculated with a trace of fluid from a 

 diseased larva which contained the vegetative form of the bacillus. 

 These tubes were then suspended in a hive between the frames 

 in order that the temperature for growth might be right. After a 

 period of 22 hours an examination was made. Observing practically 

 no spores and many bacilli in tube No. 1, and rpany bacilli in tube 

 No. 2, he reached the conclusion that many of the spores introduced 

 into No. 1 had germinated, and that the bacilli introduced into 

 No. 2 had increased by multiphcation. From this he concludes 

 that the rods were produced from the spores when suitable condi- 

 tions permitted the germination of the latter, and that the rods pro- 

 duced the spores when the reverse conditions were present. From 

 the technique used, of course, the data he obtained could be of very 

 little value. Thus Cheshire's culture experiments failed as completely 

 in demonstrating the etiology of foul brood, as did his experiment 

 with blowfly larvae. The experiment, however, is of some interest 

 as it is among the first cultural work done on bee diseases, and also 

 because here larvae of bees were used as a medium. 



Aside from the larvae, Cheshire suspected that adult bees suffered 

 from foul brood. He was of the opinion that if two colonies, a healthy 

 and a diseased one are selected for observation, and 5,000 larvae be 

 removed from the healthy one, and 1,000 larvae die of disease in the 

 diseased one, that the healthy colony will progress pretty much as 

 though it had lost nothing, while the diseased one will, as a rule^ 



