METAMORPHOSES OF INSECTS. 47 



bigness." The colorings peculiar to each species also 

 become defined and perfect as the wings expand. 



The means employed to effect a change so wonder- 

 ful with respect to the wings, and in so short a time, has 

 not been left unexplained. 



The Wings of the young Butterfly, how expanded. 

 The wings of Butterflies are composed of two fine 

 membranes between which are little veins or ribs re- 

 sembling those of the leaves of some plants. These 

 may be seen by the naked eye, when the scales, or dust 

 which colors the wings is rubbed off, and are called 

 nervures. They are hollow tubes, having a communi- 

 cation at the insertion of the wing with the body of the 

 Insect. Into these, the young Butterfly forces a quanti- 

 ty of air, and perhaps also a fluid, and by the distention 

 of which, the folds and wrinkles of the soft and wet 

 wings are in a few moments obliterated. The nervures, 

 and also the fully developed wings are shown by Fig. 35. 



These when compared with Fig. 34, will show the change 

 produced by the means above described in " half a quar- 

 ter of an hour," and at the sight of which Swammardam 

 could not help exclaiming, O ! miracle of miracles ! The 

 whole process, indeed, from the hatching of the egg, to 

 the perfection of the Butterfly, though not a miracle, be- 

 cause the whole is in the ordinary course of nature, 

 must ever be considered among the most wonderful se- 



In what manner does the butterfly make its escape from the chrysalis ? 

 Is the insect perfect when thus disengaged 1 In what manner are the new 

 wings of the butterfly unfolded and distended ' 



