We have really, that I know of, no philosophical basis for high and low. Moreover, the vegetable kingdom does not culminate, as the animal kingdom does. It is not a kingdom, but a common-wealth; a democracy, and therefore puzzling and unaccountable from the former point of view.

Perhaps if zoologists would contemplate the wide variations presented by many plants of indubitably one and the same species, and the still wider diversities of long cultivated races from an original stock, they would find more than one instructive parallel to the case of the longest domesticated of all species, man.

Natural selection is not the wind which propels the vessel, but the rudder which, by friction, now on this side and now on that, shapes the course.

This view, as a rounded whole and in all its essential elements, has very recently disappeared from science. It died a royal death with Agassiz.[It had formerly been held that there were no genetic connections among species.]