232 SOME MINUTE ANIMAL PARASITES 



sowing spores of the parasite broadcast, and pro- 

 ducing endless trouble among other bees. Such 

 individuals are known as parasite carriers. -Some- 

 times examination of several hundreds of bees from 

 a hive has failed to reveal any reason for an outbreak 

 of disease; but suddenly a parasite carrier, loaded 

 with spores, has been found, and the mystery is at 

 an end. It is worth noticing that in many cases 

 the bees die as a result of the action of the young 

 (meront) stages of the parasite. So far as the 

 particular bee is concerned, its death brings about 

 the destruction of the parasite, for the young stages 

 are frail and rapidly degenerate, and, so far, have not 

 been shown capable of cross-infection. 



Ants and earwigs visit hives to get honey. Should 

 they absorb spores of Nosema with the honey, the 

 parasites pass unharmed through their bodies, and 

 are voided unchanged with their faeces. Ants, ear- 

 wigs, and also wax moths are thus capable of 

 mechanically conveying N. apis spores from one hive 

 to another. 



The wind also 'acts as a disseminating agent, and 

 blows the finely powdered faeces containing spores 

 before it, and deposits them elsewhere. Cases are 

 known in which probably the wind has carried 

 infection from hive to hive. At any rate, the spores 

 have been traced in the dust on foliage leading 

 directly from one hive to another, and the dust was 

 only deposited on the distant and lower hive when 

 the wind fell. 



Human agency has a share also in distributing 

 disease. Stocks are moved from an infected area 



