42 



THE BACTEBIA OP THE APIABY. 



spores was secured in an agar (bee-larvse agar) made from this special 

 bouillon when Liboriiis's method for cultivating anaerobes was used. 



The technique for making cultures successfully from the diseased 

 material is not difficult if the following method is used: Place a 

 loopful of the decayed tissue of the larva^ into a tube of bouillon; 

 heat to 65° C. for 10 minutes to kill any vegetative forms which might 

 be present; incubate for 12 hours, and heat again to 65° C. for 10 

 minutes. This is usually sufficient, but it may be necessary to repeat 

 the same process. Liquefied bee-larva3 agar in a test tube is then in- 

 oculated and incubated. The successive heating will destroy the veg- 

 etative stage of any spore-producing species which is connnon about 

 the apiary, e. g.^ members of the group represented by Bacillus A^ as 

 described on pp. 13-14 of this paper. Agar slant and bouillon, when 

 inoculated from this source, remain sterile; but when bee-larvjc agar 

 is used a slow but abundant groAvth takes place. Under certain con- 

 ditions the growth ajjpears very near or at the surface when cultures 

 are made in the above manner. A surface growth can be obtained 

 after a few generations by reinoculating slant agar of this same 

 medium. 



The above method was used successfully in diagnosing the follow- 

 ing samples from different apiaries: 



Results of cxamiiiafifin of siicciniens of American foul hrood, formerJn called 



simply " foul brood." 



Brood sent by- 



W. D. Wright... 

 W. D. Wright... 

 W. D. Wright... 

 C. H. W. Weber 



N. D. West 



N. D. West 



N. D. West , 



Source. 



Canada 



Wisconsin 



Wisconsin 



Ohio 



Broome County, N. Y. . . 

 Broome County, N. Y. . . 

 Chenango County, N. Y 



Bacteriological 

 findings. 



BacillKS 

 Bacillus 

 Bacilliin 

 Bacillus 

 Bacillus 

 Bacillus 

 Bacillus 



larvse. 

 lanse. 

 larvee. 

 larvse. 

 larvse. 

 larvse. 

 larvse. 



The results of these examinations show that Bacillus larvee was 

 present in all the specimens examined, which suggests that it very 

 probably figures as an etiological factor in this disease. Other bac- 

 teria of different species are occasionally found associated with this 

 bacillus. 



Bacillus larvae. 



Occurrence. — Constantly present in diseased brood from colonies affected with 

 American foul brood. 



Gelatin. — There is no growth. 



Morphology. — It is a slender rod, having a tendency to form in chains. This 

 is especially true when grown in bee-larvfe bouillon. 



Motility. — The bacillus is rather sluggishly motile. 



Spores. — Spore formation takes place. This can be observed best in the dif- 

 ferent stages of the disease and decay of the larva^. 



Oxygen requirements. — When Liborius's method is used, the best growth 

 usually appears near to but not on the surface. After a few generations a 

 surface growth luay be obtained. 



