Chapter 9 

 INSECTS 



The little people in the trees, 

 The villages beneath the stones, 

 The gaudy butterflies, the bees 

 That hum in gentle overtones. 



All these we give to you today 

 To keep and hold for evermore, 

 To know and cherish as you may, 

 As many others have before. 



In any book on animals, the insects should occupy a large 

 place. Not only are they excessively numerous and varied, but 

 we continually meet with them, and gain or lose by their presence. 

 We lose heavily, to the extent of many millions of dollars, by 

 their depredations on our crops. The operations of man give 

 them new opportunities to spread and increase, so that the most 

 troublesome pests in many localities are species quite unknown 

 there a short time ago. The insects illustrate the balance of 

 nature, and any species would be capable of increasing its numbers 

 enormously, but for limitations of food supply and the attacks of 

 its natural enemies. This balance is frequently disturbed by 

 man, who unintentionally carries insects to new localities, where 

 the normal checks on increase do not exist. Hence a species 

 which is harmless in one place, may ruin the farmers in another. 

 In consequence of these facts, we have entomological quarantine, 

 and frequently entomologists are sent out to the uttermost parts 

 of the earth to search for appropriate natural enemies. The 

 citrophilus mealy-bug, which arrived in California, no one knows 

 whence, a number of years ago, would ruin the citrus industry 

 (with a product which in 1925 was worth over 97 million dollars), 

 were it not kept down by an imported ladybird beetle. The 

 discovery and utilization of this beetle is due to the work of a 

 number of technical experts, without whose services disaster 

 would come to a large section of the country. On the other hand, 

 we may profit greatly by the insects; the products of the honey- 

 bee and the silkworm, commercially valuable as they are, repre- 



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