348 THE HISTORY OF CREATION, 
organic individual, without having an idea of the palzon- 
tological history of the whole tribe, of which fossils are 
the records. And yet these two branches of the organic 
history of development—ontogeny, or the history of the 
individual, and phylogeny, or the history of the tribe— 
stand in the closest causal connection, and the one cannot 
be understood without the other. The same may be said of 
the systematic and the anatomical part of Biology. There 
are even now, in zoology and botany, many systematic 
naturalists who work with the erroneous idea that it is 
possible to construct a natural system of animals and plants 
simply by a careful examination of the external and readily 
accessible forms of bodies, without a deeper knowledge of 
their internal structure. On the other hand, there are 
anatomists and histologists who think it possible to obtain a 
true knowledge of animal and vegetable bodies merely by a 
most careful examination of the inner structure of the body 
of some individual species, without the comparative exami- 
nation of the bodily form of all kindred organisms. And 
yet here, as everywhere, the internal and external factors, 
to wit, Inheritance and Adaptation, stand in the closest 
mutual relation, and the individual can never be thoroughly 
understood without a comparison of it with the whole of 
which it is a part. To those one-sided specialists we should 
like in Goethe’s words to say :— 
We must, contemplating Nature, 
Part as Whole, give equal heed to: 
Nought is inward, nought is outward, 
For the inner is the outer.* 
* Miisset im Naturbetrachten 
Immer Eins wie Alles achten. 
Nichts ist drinnen, Nichts ist drauszen, 
Denn was innen, das ist auszen. 
