CHAPTER XXXVI 



INSECTS 



Man's two greatest enemies are himself and insects. 

 The best friends he has among insects are the cannibal 

 insects, those that serve him by devouring other injurious 

 forms. Bees yield us honey, and silk comes from the 

 cocoons of a certain moth, but how gladly we should give 

 up silk and honey if thereby we could escape the harm 

 that other insects do to our crops and to our very lives! 

 The common house-fly is the most dangerous animal in 

 the world; it carries typhoid fever. And there is a kind 

 of mosquito that spreads malaria from patient to patient. 

 Altogether, we seem to be a good deal at the mercy of 

 insects. Flies and mosquitoes we can drive out if we take 

 the trouble to do so, but there are many insect enemies 

 of our important plants that we do not know how to con- 

 trol. The gypsy and the brown-tail moths are very injuri- 

 ous to shade-trees, and millions of dollars have been spent 

 in Eastern United States in trying to control them, and yet 

 their ravages continue. Our annual financial loss due to 

 insects is estimated as follows: 



Cereals $300,000,000 



Hay and forage , 66,500,000 



Cotton 85,000,000 



Tobacco 10,000,000 



Truck crops 60,000,000 



Sugar 9,500,000 



Fruit , 60,000,000 



Farm products 11,000,000 



Miscellaneous crops 10,000,000 



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