CHAPTER IV 



THE FLY'S ENEMIES 



THE fly has no friends; she has enemies. Her eggs 

 are frequently eaten by fowls. The poultry which 

 stalk about the farmyard feed gladly on fly-maggots. 

 Watch the old hen teach her chicks to eat the fly- 

 larv. It would be very disappointing for the mother- 

 fly to realise, if she could, that her offspring instead of 

 spreading disease among human beings had merely 

 become food for fowls. It would be an ambition 

 blasted in its realisation. Probably other birds also 

 feed on fly-eggs, larva?, and pupae sparrows, starlings, 

 pigeons, ducks ; but there is little certain knowledge 

 of this. On the other hand, some species of ants 

 undoubtedly feed on fly-maggots and nymphs. These 

 will invade the manure-heap and soon rid it of the fly- 

 eggs and caterpillars. Unfortunately, it is not possible 

 to apply ants to every manure-heap, so this method of 

 fly-reduction is not practicable ; it is much easier to 

 remove the manure-heap once a week. Most beetles 

 avoid fly-larvae and manure, though a few species have 

 a partiality for both. There is a well-known beetle in 

 South Africa and India which spends its life rolling 

 horse-manure into balls and trundling them up and 

 down the road ; but whether such beetles eat the 

 fly-maggots is unknown. 



The enemies of the adult fly are more numerous 



40 



