17 



discouragement arising therefrom is oae of the two influences that retard the 

 development of the bee industry. 



In the United States, serious harm has been done, but no definite statis- 

 tics can be cited. The disease causes great losses and several States have 

 enacted laws for the prevention of the disease, making it a legal oflFence for a 

 person to keep in his apiary a colony of bees aflfected with foul brood. 



In Canada, the Ontario Foul Brood Inspector (56) reports in the years 

 1890 1892 inclusive, 622 apiaries inspected and 2,395 cases; in the years 

 1893-1898, 527 apiaries inspected and the disease present in 212, or about 40 

 per cent. 



In New Zealand and Australia, the disease is looked upon as being very 

 wide spread. It will thus be seen that wherever bees are kept, serious losses 

 are caused annually by this disease. 



Natural method of Infection. "With regard to the natural methods of 

 infection, a good deal depends on the natural prediepssition of the bees to 

 disease and the state of health of the colony. Weak, sickly, or badly nour- 

 ished bees are as a rule the most susceptible. We must also remember that 

 germs themselves vary in their ability to produce di^easa As in 

 diphvheria, we may get a light or severe type of the disease ; so also in foul 

 brood, we may have a light or a severe attack ; but the facts demonstrating 

 the variability of this capacity are not well known ; I have, however, noticed 

 that after prolonged cultivation of B alvei in which more than 30 transfers 

 have been made, and the bacteria with spores have been given to bees in 

 syrup, the virulence of the germ has seemed to be considerably impaired. 

 In one case the colony experimented with was rather weak, was confined to 

 the hive all day, and allowed flight only in the evening, and the spores 

 were given in large quantities in syrup every day, nevertheless it was several 

 weeks before the disease established itself, and then only in a light form So 

 we may have mild or severa epidemics and the liability to' take the disease 

 may be increased by chillin» the bees or otherwise unfavourably modifying 

 their metabolism ; and in all such cases, they succumb more easily to the dis- 

 ease than when in a normal, healthy condition. 



With regard to the manner in which the disease is carried from hive to 

 hive, Cheshire (26) thinks that the larvae are most usually affected by the 

 antennae of the nurse bees, and also that the tramp of the bees frequently 

 detaches numbers of spores, which fly about in the air and fettle here and 

 there, often where they take eflTect. I think that in comparison with other 

 diseases which are air borne there is usually not very much danger from this 

 cause in the Joase of B. alvei. The spores are generally found in very sticky 

 surroundings, which, even if dry, serves to fix and keep them in situ. Ohes- 

 shire also states that he has not found the bacillus from honey or pollen in 

 infected hives. This statement, however, is directly contradicted by the 

 experience of practical beekeepers and others. I have myself repeatedly 

 found B. alvei in capped honey cells, and in the pollen mai^ses found in 

 diseased hives, the examination in the former case having been made by 

 removing the capping with steriliz<;d forceps and plunging a heated platinum 

 needle into it and then pnlting the needle into melted agar, from which plates 

 were poured, cooled and incubated. 



Probably the chief method of c*rrying the disease from one hive to 

 another is by the bees from healthy hives robbing colonies that have become 

 weak and diseased. In such cases the robbers carry with them the germs of the 

 disease. There is likely nothing to be feared from using wax foundation 

 from the regular makers ; for, as we have already stated, the wax, in the 

 2—112 



