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THE WORLD OF ANIMAL LIFE 



Gardeners often call these insects the "green blight", and 

 dislike them because of the great damage which they do to roses, 

 and to many of the plants in gardens and in greenhouses. But 

 another and more correct name for this green fly, or green blight 

 insect, is the "Aphis". 



By the appearance of a single aphis, we find it very hard to 

 understand how it can do so much mischief. What a small 

 creature it is, and how feeble and helpless it seems! 



Yet farmers tell us that it sometimes destroys whole fields of 

 corn and beans, while it is hardly possible to describe the injury 



which it causes to hops. A 

 hop-garden may be full of 

 strong, healthy plants, all 

 twining round and round 

 the poles, and covered 

 with blossoms. But a week 

 later one may see nothing 

 but withered stems and 

 dry and dead leaves. That 

 is the work of the aphis! 



It increases in numbers 

 so fast, that where there is 

 one aphis to-day, there 

 will be two or three hun- 

 dred in a day or two's time; and a few days later there will be 

 three hundred times three hundred, and in very brief time, count- 

 less millions. It has been found that a single aphis, before it dies, 

 may have more than six thousand million descendants — four times 

 as many as there are people in the whole world ! 



This seems very marvellous, but it is quite true. Indeed, if vast 

 numbers of these mischievous creatures were not killed by other 

 insects, and by birds, they would very soon prevent us from 

 cultivating any crops at all. 



The aphis has no jaws, but it has a beak which it drives 

 into the leaves or the bark of its food-plants, and so sucks up 

 their sap. 



One or two, or a dozen, or twenty aphides could do little harm ; 



I, Aphis (highly magnified); 2, Same on plant leaves; 

 3, Winged Aphis (highly magnified); 4, Natural size 



