circumstances, it was open to the paleontologist to multiply species almost ad libitum; if he had adopted a theory which required that no species found in one stratum should be found in another, it was easy to make the most of slight variations of form. Differentiations of species thus made, however, were essentially subjective; all that could conceivably have been proven objectively was that no form remained the same through successive geological periods. Yet even of this no proof was forthcoming; the geologic record was not the sort of document that could furnish proof for a universal negative. It furnished, in fact, evidence on the other side. Even Cuvier's eulogist had been obliged (1841) to limit the generalization by adding "at least among mammals and reptiles"—and then to make further exception of two orders of mammals. And Hitchcock in his "The Religion of Geology" (1852), while exaggerating the discontinuity of then known types, could say no more than that, "of the thirty thousand species of animals and plants found in the rocks, very few living species can be detected." But a few were as good as a multitude as witnesses to the fact that there had been no such complete, simultaneous extinctions of faunas, and radical alterations of terrestrial conditions, as the Cuvierian theory supposed.[1] And we find Chambers, in 1844, citing specific examples of persistency, as Huxley was to do fifteen years later.
There is a badger of the Miocene which can not be distinguished from the badger of the present day. Our existing Meles taxus is therefore acknowledged by Mr. Owen to be "the oldest known species of mammal on the face of the earth." It is in like manner impossible to discover any difference between the existing wild cat and that which lived in the bone caves with the hyæna, rhinoceros and tiger of the ante-drift era, all of which are said to be extinct species. . . . There is a persistency of certain shells since the beginning of the tertiaries. . . . Several shells of the secondary formation straggling into the tertiaries are not less conclusive, in rigid reasoning, that all the tertiary species were descended from the secondary, though the wide unrepresented interval at that point allowed a greater transition of forms. In short, the whole of the divisions constructed by geologists upon the supposition of extensive introductions of totally new vehicles of life must give way before the application of this rule, and it must be seen that what they call new species are but variations of the old.[2]
7. The Argument from the Recapitulation Theory.—In charging Chambers with prematurity in his acceptance of evolutionism, Professor Le Conte urged that "the foundation, the only solid foundation, of a true theory of evolution" is to be had solely in "the method of
- ↑ It was, indeed, possible to restate the special creation theory so as to avoid this difficulty; extinctions and fresh productions of species, one at a time, might be supposed to have taken place continuously, without any general or widespread "revolutions of the globe." Such a conception was put forward by Bronn in 1857. But when thus amended the theory was pretty manifestly in a state of hopeless overstrain. It now made miraculous interpositions a matter of, so to say, almost daily occurrence in the geologic history.
- ↑ "Explanations," 1846, p. 108 f.
