ANCESTRY AND CLASSIFICATION. 



studying the natural history of insects is the curi- 

 ous character of their metamorphoses. Those of 

 butterflies are perhaps as complete as any, and 

 differ widely from the transformations of the 

 lower insects, grasshoppers for example, where 

 the young animal is born with a very close resem- 

 blance to its parent. Has this disparity between 

 the different tribes of insects always existed, since 

 insects were \ Or if not, what was the nature 

 of the changes undergone by the primitive insect 

 during its existence ? And what have been the 

 steps by which the passage has been made from 

 homogeneous to dissimilar metamorphoses \ Since 

 the history of life everywhere shows continuous 

 progress from a simple to a complex condition, it 

 may be presumed that the more uniform meta- 

 morphoses of the grasshopper have preceded the 

 more complicated changes we have discussed in 

 butterflies. But is there in the present structure 

 of these insects any evidence of such a presump- 

 tion ? The differences themselves between the cat- 

 erpillar, chrysalis, and imago of the butterfly we 

 have given in detail. The only distinction of im- 

 portance between the young and fully grown grass- 

 hopper, on the other hand, lies in the absence, in 

 the former, of wings. These are assumed during 

 growth, and so gradually that it has been asserted 

 there are no distinctive larval and pupal stages, 

 as in insects generally. This, however, is a mis- 



