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importance. This can be done in many wa3's. as is the fol- 

 lowing chapter's aim to show. 



In order to gain the best results, however, everything should 

 be done in accordance with the insect's habits and life-history. 

 Hap-hazard remedies may or may not be of use in the fight. 

 Where nature can be made or assisted to do the work for- 

 us so much is gained; but when this cannot be done artificial 

 methods alone will win if persisted in and followed aright. 



Invertebrate Enemies. 



It is a well known fact, among naturalists at least, that all 

 kinds of animals, whether they be insects, molluscs, reptiles, 

 birds or mammals, or for that matter, any of the remaining 

 groups, have their natural enemies. Should anyone care to 

 learn whether or not destructive locusts are included under 

 this rule it might be well for such a person to read the chapters 

 devoted to the invertebrate and vertebrate enemies of the 

 Rocky Mountain Locust ( Melaiiopliis spretiis ) as published 

 in the first annual report of the United States Entomological 

 Commission, chapters XI and XII, pages '284 to 350. Since these 

 chapters were written it is but just to say that much additional 

 information on the same topic has accumulated so that what 

 is there recorded could be greatly extended. 



Although comparatively little has thus far been written on the 

 natural enemies, insect and other, of the locust now under 

 consideration, it can be taken for granted that it has equally 

 many if not more of them than the insect above referred to. 

 The Rocky Mountain Locust is a native of a comparatively 

 cool countr\^ Avhile the Argentine species is confined more to 

 a subtropical region where animal life of all kinds is ver}' 

 much more abundant. 



Some of the invertebrate enemies of this last named insect 

 are already known and the following may be mentioned here 

 as being among the more important. 



