Note 245 — Front matter (continued 3)

Darwin (Origin of Species, p. 274, 6th Edition) considers it "incredible" that the same identical species should originate twice even under the very same conditions. In the following passage, Haeckel affirms such unity of origin in respect of a most remarkable species of wide-reaching affinities.

"All morphologists arrive at the firm conviction that all vertebrata, from the Amphioxus upwards to man himself, all fishes, amphibia, reptiles, birds, and mammals, descend originally from a single vertebrate ancestor, for we cannot imagine that all the different and highly complicated conditions of life which, through a long series of processes or stages of development, led to the typical formation of a vertebrate, have accidentally happened together more than once in the course of the earth's history." (Address to Munich meeting of German Association, vid. Nature, October 4, 1877.)