The Isle of Wight Bee Disease. 69 



occupying old infected hives. Wet weather, especially when 

 accompanied by cold, affords plenty of chances for bees to 

 obtain moisture close to their hives, which becomes contami- 

 nated by the excrements discharged on the latter. There is 

 evidence to indicate that partial immunity of stocks happens : 

 such stocks might be difficult to diagnose, though they would 

 at the same time act as sources of infection for susceptible 

 colonies. 



Certain other insects associated with bee hives, siach as the 

 wax-moths, wasps, ants, and possibly the death's head moth, 

 may occasionally act as mechanical carriers of spores from one 

 hive to another. Fantham and Porter have found that if house 

 flies, blue bottles, wasps, mason bees, or sheep ticks be infected 

 by Nosema spores they succumb to the effects of the latter. 



Remedial and Preventive Measures. 



Many remedies have been brought forward, but there 

 appears to be little evidence that any of them result in effect- 

 ing permanent cure for the disease, though temporary 

 amelioration may not infrequently be obtained. The most 

 satisfactory measures so far discovered are preventive rather 

 than curative. Healthy stocks should be removed from the 

 neighbourhood of diseased hives. The water supply should 

 be rigidly attended to ; clean water changed daily should be 

 readily accessible and protected from contamination. The 

 usual drinking places should if possible be removed. All 

 dead bees should be burnt and diseased colonies destroyed. 

 The ground around the hives should be dug over and treated 

 with quick lime. Infected hives and the parts associated 

 with them should be charred with a painter's lamp. In the 

 place of charring a very thorough application of formalin or 

 carbolic acid may be used, and the hives afterwards properly 

 aired in strong sunlight. 



The application of heat as a preventive measure has 

 recently been studied in America (White, 1914). An aqueous 

 solution of spore-containing material obtained. from the chyle 

 stomach of diseased bees was placed in a small glass tube and 

 heated. Afterwards it was mixed with syrup and given to 

 healthy bees, and it was found that a minimum temperature 

 of approximately 57° C. (134-6° F.) applied for ten minutes 

 renders the spores of Nosema apis innocuous. The hives and 

 all implements used in apiculture could therefore probably be 

 sterilized at this temperature or one slightly higher. Even the 

 combs would suffer no harm in the process as the melting 

 point of beeswax lies between 62" C. (14.3-6" F.) and 64" C. 

 (147-2° F.). Experiments on the American lines need to be 

 carried out in England in order to ascertain whether the 



