MEANING OF ORDERS. 75 
clings to us; and where the different phases of 
the same life assume such different external 
forms, we are apt to overlook the fact that it is one 
single continuous life. Toa naturalist, metamor- 
phosis is simply growth; and in that sense the 
different stages of development in animals that 
undergo their successive changes within the egg 
are as much metamorphoses as the successive 
phases of life in those animals that complete their 
development after they are hatched. 
But to return to our Butterfly. In its most 
imperfect, earliest condition, it is Worm-like, the 
body consisting of thirteen uniform rings; but 
when it has completed this stage of existence, it 
passes into the Chrysalis state, during which the 
body has two regions, the front rings being sol- 
dered together to form the head and chest, while 
the hind joints remain distinct; and it is only 
when it bursts from its Chrysalis envelope, as a 
complete Winged Insect, that it has three distinct 
regions of the body. Do not the different periods 
of growth in this highest order explain the rela- 
tion of all the orders to each other? The earliest 
condition of an animal cannot be its highest con- 
dition, —it does not pass from a more perfect to 
a less perfect state of existence. The history of 
its growth is, on the contrary, the history of its 
progress in development; and therefore, when 
we find that the first stage of growth in the 
