Masterpieces of Science 



which they were formerly so anxious to wipe 

 out of existence ! With the Scutellista parasite 

 the same fact holds. The fly itself does not feed, 

 and its young feed only upon certain scale 

 insects, and so with all the rest. 



All of these experiments are being carried 

 on by men learned in the ways of insects, and 

 only beneficial results, or at the very least 

 negative ones, can follow. And even where only 

 one such experiment out of a hundred is 

 successful, what a saving it will mean ! 



"We do not expect the time to come when 

 the farmer, finding Hessian fly in his wheat, 

 will have only to telegraph the nearest experi- 

 ment station, "Send at once two dozen first- 

 class parasites;" but in many cases, and with a 

 number of different kinds of injurious insects, 

 especially those introduced from foreign countries, 

 it is probable that we can gain much relief by the 

 introduction of their natural enemies from their 

 original home. 



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