142 



F'LASHLIGHTS 0\ XATIRE 



earlier staj^c, and is hatclied out in tlic form of 

 a crawling worm a type which must have be- 

 longed to a much more orij^inal ancestor. It 

 passes the first stai^e of its life in this worm-like 

 form, but it does not jfrow by slow dej^rees, like 

 the earwig, into its final shape. On the ciHitrary, 

 it suddenly boxes itself up one day in a pupa-case, 



NO. 17.— THK MOTllF.R K AKWIC SITIINC. ON UF.R KdCS. 



or chrvsalis, lies by dormant for a while, rearranj^cs 

 its parts entirely, and then rapidly develops into a 

 wholly dilferent creature — a bee or wasp, or moth 

 or beetle. The earwis^'s change is growth ; the 

 buttertlv's is a transformation scene. 



How are we to explain these facts ? I think in 

 this way. Long, long ago, the comnn^n progenitor 

 of all the insect tribes was a worm-like creature, 



