Insect Characteristics 



out into a caterpillar which feeds by biting leaves, 

 moults half-a-dozen times or so, finally becoming a 

 chrysalis without legs or wings, almost quiescent, 

 and doing no feeding, which in its turn becomes a 

 moth which crawls out of the chrysalis case, dries 

 its wings, feeds by sucking the nectar of flowers 

 through a long tubular mouth, and which lays eggs 

 (if a female) before it dies, usually on or near the 

 caterpillar's food plant. This progression is less 

 readily seen in such insects as greenflies, where, 

 although it exists, the changes are less profound 

 and the insect is active in all its stages. 



Reference has just been made to the different 

 modes of feeding seen in the adult moth as con- 

 trasted with the caterpUlar. The former obtains 

 its food by sucking, the latter by biting. This 

 distinction is very important, and serves to divide 

 two great groups of insects from one another so far 

 as their work in the garden goes, viz. those which 

 bite, and those which pierce the tissues of plants 

 and suck the sap. The latter thus obtain their food 

 from the interior of the plant, and it is impossible to 

 poison their food without at the same time killing the 

 plant ; the former eat both inner and outer parts of 

 the plant, and it is possible to cover the food with a 

 poison which will not find its way into the plant, 

 but which will be swallowed, and will kill any insect 

 that bites the plant. This method of attack cannot 

 of course be followed in dealing with those insects 



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