THE EVIDENCE FROM THE LIFE-HISTORIES OF INSECTS. 253 



their excellence or, it may be added, in all their frequent and 

 apparent imperfections at the behest of some sudden creative fiat. 

 There is no need to assume development at all on this hypothesis of 

 things, which for the man of science has been slain long ago ; though 

 traces of its influence are not unknown in regions removed from the 

 active currents and tides of culture. On the reverse side of matters, 

 stands the theory broadly denominated " evolution," which, seeing 

 the promise of reading a past and progressive history in the develop- 

 ments which pass in panoramic review before our eyes to-day, 

 asserts that a law of progress has guided and still guides life's courses 

 and ways. On this theory we can understand why development 

 takes place namely, because it is a law of life that the progress and 

 growth of the race should be represented in, and carried out through, 

 its individual histories. And we can also conceive why development 

 should run in the grooves marked out so conspicuously in many life- 

 histories, such as those of insects and crustaceans. This latter fact is 

 explicable when it is repeated that we see in an animal's early growth, 

 the lines and stages along which the development of its race has 

 passed. By the very idea of evolution we expect variety and change to 

 be represented in the development of living beings ; for such change 

 is the one great condition which has made this universe what it is. 

 Agreeing as to the main reasons for development and its ways, we 

 should find little difficulty in comprehending how these ways and 

 paths have been followed. As we have already impressed upon the 

 reader, the picture is not always clearly limned, and its outlines are 

 often meagre enough. Still, what we do see and know of its form, 

 convinces us of the correctness of the broad deductions of evolution ; 

 which deductions being scorned and denied, leave the whole course 

 of nature a tissue of inexplicable absurdities. 



In the present instance, dealing with the meanings of meta- 

 morphosis, we intend to direct attention to certain details which, for 

 lack of space, have been omitted in previous chapters, and which, 

 dealing with matters of special interest to the student of evolution, 

 may, logically enough, claim attention in a separate section. Such 

 subjects as the general nature of "metamorphosis," and how that 

 process is modified by surroundings and other circumstances, as well 

 as the narration of some life-histories which illustrate very aptly the 

 general conclusions of evolution, may therefore fitly engage our con- 

 sideration in the course of our developmental studies. 



Firstly, then, the general question of "metamorphosis " demands 

 notice. Whilst it is perfectly true that, broadly speaking, only such 

 animals as insects, crustaceans, and frogs exhibiting very marked 

 and apparent change of form in passing from the young to the adult 

 stage may be said to undergo " metamorphosis," it would be far 

 more logical, because more true, to assert that the histories of all 



