A page from one of Vladimir Nabokov's butterfly books.
Transformation is a marvelous thing.
I am thinking especially of the transformation of butterflies. Though wonderful to watch, transformation from larva to pupa or from pupa to butterfly is not a particularly pleasant process for the subject involved. There comes for every caterpillar a difficult moment when he begins to feel pervaded by an odd sense of discomfort. Of course he has molted a few times before but that is nothing in comparison to the tickle and urge that he feels now. He must shed that tight dry skin, or die.