The Life of the Fly 



fuse to lay on the sand, apparently for the 

 same reasons. The paper was considered an 

 obstacle which the frail vermin would not be 

 able to overcome. With sand, the case is 

 worse. Its grittiness would hurt the new- 

 born weaklings, its dryness w^ould absorb the 

 moisture indispensable to their movements. 

 Later, when preparing for the metamorpho- 

 sis, when their strength has come to them, the 

 grubs will dig the earth quite well and be able 

 to descend; but, at the start, that would be 

 very dangerous for them. Knowing these dif- 

 ficulties, the mothers, however greatly tempted 

 by the smell, abstain from breeding. As a 

 matter of fact, after long waiting, fearing lest 

 some packets of eggs may have escaped my 

 attention, I inspect the contents of the jar from 

 top to bottom. Meat and sand contain neither 

 larvae nor pupas : the whole is absolutely de- 

 serted. 



The layer of sand being only a finger's- 

 breadth thick, this experiment requires certain 

 precautions. The meat may expand a little, in 

 going bad, and protrude in one or two places. 

 However small the fleshy eyots that show 

 above the surface, the Flies come to them and 

 breed. Sometimes also the juices oozing from 

 the putrid meat soak a small extent of the 

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