164 SOME SUGGESTIONS FOR THE STUDY OF INSECTS. 



These changes can best be understood by a consideration 

 of the distribution of the functions of the insect over the 

 whole period of the life-history. In many insects, e.g. in 

 the moth we are at present study in or, the prime functions 

 of life are set in apposition in different life stages with 

 marked definiteness. In the larva, feeding is the dominat- 

 ing function. It is accompanied by growth. We see in it 

 a period given over to the Individual Interest. In the 

 adult, feeding is quite a subsidiary function, being sub- 

 servient to that of egg-laying, i.e. the continuance of the 



Fig. 62. Head of Magpie 

 Moth, showing coiled 

 sucking jaws. 



Fig. 63. Head of Cabbage 

 Butterfly showing clubbed 

 antennae and coiled mouth 

 parts. (Cf. Fig. 62.) 



species. Adult insects do not grow. This period is given 

 over to the Race Interest. 



A detailed examination of the various parts of the insect 

 in the light of these facts is not possible here, but some 

 points should be touched on, and some of them may profit- 

 ably be suggested to senior pupils. 



Antennae or feelers are, as experiment has shown, also 

 important as organs of smell. The caterpillar hatches 

 from the egg upon its food plant and commences to eat 

 right away, and on the whole abundant supplies are 



