NATURAL HISTORY OF SOUTH AFRICA 



up as the result of this dishonest deal, those robbers of 

 the people's money got a most unpleasant surprise. 

 The entire stock of grain had been destroyed by 

 weevils. 



Birds are Nature's principal enemies of beetles. 



FLIES 



Flies are distinguished from all other insects by 

 possessing only two wings. The second pair are 

 rudimentary, and are reduced to stalked knobs called 

 balancers. 



The mouth parts are modified for sucking and 

 piercings 



Their life history is the same as that of beetles and 

 butterflies, viz., the egg (ova), maggot (larva), chrysalis 

 (pupa), and adult fly (imago). A few species of flies 

 incubate the eggs within their bodies ; the majority 

 produce eggs. 



With two or three exceptions, the flies of the order 

 Diptera are a terrible curse to man. The common 

 house fly (Musca domestica) is a world-wide pest. 

 It breeds chiefly in fresh stable manure (horse, mule, 

 and donkey manure). Failing this, it will breed in 

 human excrement, moist decaying garbage, etc. Its 

 whole life history from egg to mature fly averages 

 fourteen days. The eggs hatch a few hours after 

 being laid ; the maggots feed greedily for eight days 



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