40 THE HISTORY OF CREATION. 
accumulation of cells, and out of these, by division of 
labour (as has previously been described), there arise 
the numberless different forms which are presented to us 
in the fully developed animal and vegetable species. This 
immensely important process—which we may follow step 
by step, with our own eyes, any day in the embryological 
development of any animal or vegetable individual, and 
which as a rule is by no means considered with the 
reverence it deserves—informs us more surely and com- 
pletely than all petrifactions could do as to the original 
paleontological development of all many-celled organisms, 
that is, of all higher animals and plants. For as ontogeny, 
or the embryological development of every single individual, 
is essentially only a recapitulation of phylogeny, or the 
paleontological development of its chain of ancestors, we 
may at once, with full assurance, draw the simple and 
important conclusion, that all many-celled animals and 
plants were originally derived from single-celled organisms. 
The primeval ancestors of man, as well as of all other 
animals, and of all plants composed of many cells, were simple 
cells living isolated. This invaluable secret of the organic 
pedigree is revealed to us with infallible certainty by the 
egg of animals, and by the true ege-cell of plants. When the 
upponents of the Theory of Descent assert it to be miraculous 
and inconceivable that an exceedingly complicated many- 
celled organism could, in the course of time, have proceeded 
from a simple single-celled organism, we at once reply that we 
may see this incredib:e miracle at any moment, and follow it 
with our own eyes. For the embryology of animals and 
plants visibly presents to our eyes in the shortest space of 
time the same process as that which has taken place in the 
