by J. Arthur Thomson (Author), August Weismann (Author), Ernst Haeckel (Author)

As an epoch-marking contribution to Natural History in the widest sense, we rank the picture which Darwin gave to the world of the web of life, that is to say, of the inter-relations and linkages in Nature. For the Biology of the individual--if that be not a contradiction in terms--no idea is more fundamental than that of the correlation of organs, but Darwin's most characteristic contribution was not less fundamental, --it was the idea of the correlation of organisms