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The Great World's Farm 



for instance, the tiger is as useful to the farmer as owl 

 and hawk are here. If he kills off the tigers, as his Eng- 

 lish brother kills the birds of prey, then the deer multiply 

 and eat his crops; and on the other hand, if he kills off 

 the deer, the tigers kill him, for even a tiger must live! 

 so that on the whole he finds it better not to interfere. 



Insects are, as a whole, such enemies of vegetation 

 that we are apt to condemn them in a body. Yet besides 

 the many which convey pollen there are a few others 

 which deserve honorable mention, and even the name of 

 friends. These few are positive benefactors, for they 

 leave the green things alone themselves and prey upon 

 other mischievous insects. 



Among these insect-friends is the lady-bird, to whom, 

 as an American writer says, 'Sve should take off our 

 hats," for it destroys those terrible pests, thrips and 

 greenflies. 



Wasps carry off flies and caterpillars to feed their 

 young grubs; and some species of ichneumon-fly deposit 

 their eggs in the chrysalides of moths and butterflies, as 

 weU as in grubs and caterpillars, thereby killing them. 

 But of all insects, perhaps some of the beetles are the 

 most useful, for both in the grub and in the winged state, 

 they catch and devour living prey. 



To sum up: without insects many plants would be 

 unable to produce seed, and so must in time die out; 

 without the small birds, insects would increase so much 

 that all green things would be destroyed; and without the 

 birds of prey to keep the number of small birds within 

 bounds, not only would farming be quite impossible, but 

 wild plants would also suffer; for when the insects were 



