DANGERS FOR BEES 231 



known cases where wasps have been exterminated, 

 as the larvae have succumbed to Nosema apis, acquired 

 by a diet of dead bees. 



One of the most fertile agents in the spread of 

 N. apis, and one that is least under control, is afforded 

 by the drinking-places of the bees. Water is a 

 necessity for bees, especially in the early spring 

 before the honey flow has commenced. Bees prefer 

 water that is slightly warm to that which is colder, 

 even though the latter is far purer. When disease 

 appears in these neighbourhoods, the drinking-places 

 soon become fouled, and the small pools at which 

 the bees prefer to drink are rapidly contaminated 

 with faeces of infected bees, and so become veritable 

 death-traps. When there is a spell of wet weather, 

 the bees will issue from the hives between storms 

 and drink at the nearest puddles. If the soil around 

 the hive has become contaminated, and it usually is, 

 the spores are washed into the tiny pools, and are 

 easily acquired by the thirsty bees. Water is also 

 stored in some cells in the hive, and if infected water 

 is so stored, the brood to whom it is supplied may 

 perish. Much disease among bees can be avoided 

 if readily accessible supplies of pure water are pro- 

 vided regularly for them. 



But there is one danger that it is impossible for 

 any beekeeper to guard against. Certain bees have 

 become immune to the effects of N. apis, which 

 flourishes within their bodies and produces its spores 

 without apparently causing any discomfort to the 

 insects. The latter live about as long as healthy, 

 uninfected bees, but throughout their lives they are 



