sa ON ANIMAL LIFE 43 
ments we find the utmost differences of form 
and size and structure. Even the same in- 
dividual often goes through great changes. 
GROWTH AND METAMORPHOSES 
The development, indeed, of an animal 
from birth to maturity is no mere question 
of growth. The metamorphoses of Insects 
have long excited the wonder and admiration 
of all lovers of nature. They depend to a 
great extent on the fact that the little 
creatures quit the egg at an early stage of 
development, and lead a different life, so 
that the external forces acting on them, 
are very different from those by which they 
are affected when they arrive at maturity. A 
remarkable case is that of certain Beetles 
which are parasitic on Solitary Bees. The 
young lava is very active, with six strong 
legs. It conceals itself in some flower, and 
when the Bee comes in search of honey, leaps 
upon her, but is so minute as not to be per- 
ceived. The Bee constructs her cell, stores it 
