30 HISTOBICAL NOTES ON BEE DISEASES. 



The sample of comb which Chesliire gave to Cheyne for examination 

 then was considered by Cheshire to be foul brood, and therefore was 

 thought by the latter to be a sample of the only form of the disease 

 that exists under this name. Further Chejme writes, "selecting cells 

 which were closed, but which Mr. Cheshire thought contained dis- 

 eased larvae, * * *." This statement indicates that Cheyne 

 was unfamiliar with the gross appearance of the disease as it is found 

 in the combs. After uncapping the cells containing foul-brood larvae, 

 he further writes, "these larvae were dead, of a yellowish colour, 

 and almost liquid, * * *." Capped cells occur more often in 

 American foul brood, but are not rare in European foul brood. The 

 yellowish color and the almost liquid condition are symptoms which 

 would rather strongly suggest that the sample which he examined was 

 European foul brood. Numerous rods were found microscopically in 

 the diseased larvae. Cultures were made in gelatin and in agar. The 

 bacteria found in the larvae and those which appeared in the cultures 

 by comparison seemed to be the same. The morphology and cultural 

 characters of this bacillus {Bacillus alvei) were carefully studied. 



Concerning the method by which multiplication takes place, Cheyne 

 writes : 



The bacilli appear to grow mainly by fission, but I have seen appearances which 

 seem to me only explicable on the supposition that they also grow by sending out buds 

 from one end. 



A study of the germination of the spores was made, using the 

 hanging-drop preparation. A drop of bouillon was placed on a cover- 

 glass, moculated with the spores of Bacillus alvei, and inverted over a 

 cell in a glass slide. Preparations made in this manner were placed 

 at a temperature favorable for the growth of the bacteria, and from 

 time to time studies were made of them by the aid of the microscope. 

 He writes: 



In three hours the first indication of sprouting of these spores becomes evident. 

 The stained part of the spore loses its oval shape, becomes elongated, and is soon seen 

 to burst through the spore-capsule at one part. 



From this it is not possible to know whether he observed the capsule 

 to burst on the side or at the pole, but the figure to which he refers 

 shows the rod bursting through the capsule at or near the pole. 



Having studied the germination of the spores, he proceeded to 

 study the formation of the spores in the rod. In domg this two 

 methods were employed. The first was by use of the hanging drop, 

 similar to that used in his study of the germination. By this method 

 he observed in one preparation that most of the rods were beginning 

 to form spores in 23 hours, while in another preparation where more 

 bouillon was used no evidence of spore formation was present during 



