CREATION BY EVOLUTION
due less to Milton than to the faith of his fellow Puritans in the verbal inspiration of the Bible.
The formal definition or establishment of species was practically begun by Milton's contemporary, John Ray, an Essex naturalist (1627-1705). Ray founded many of the species of the British flora and prepared the way for Linnaeus (1707-1778), whose system was based upon implicit faith in the immutability or fixity of species. Linnaeus declared, in a famous dictum, that "the number of species is as many as different forms were created at the beginning." In the following century Cuvier was equally positive. He believed that species are as distinct as the different makes of boots sent out from a factory. Darwin, on the contrary, called his epoch-making treatise "The Origin of Species," because he maintained that species pass into one another; and the doctrine that one species may be derived from an earlier allied species is the doctrine of organic evolution. He regarded the term species as one arbitrarily given, for convenience of designation, to a set of individuals closely resembling one another—as a term not essentially different from the term variety, which is given to less distinct and more fluctuating forms.
Darwin's theory was opposed to preconceived opinion. The species of the more highly organized animals and plants appear to be sharply separated. The differences between the African and Asiatic rhinoceros, between the African and the Indian elephant, between the one-humped and the two-humped camel, appear to be constant and absolute. Nevertheless, when such animals are examined carefully it is found that individuals in different herds of each kind show slight but significant differences. The giraffes, which were at first classified as one species, have been broken up into eleven subspecies; the African elephant has been found to include more
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