Page:Popular Science Monthly Volume 75.djvu/549

Rh comparison of the phylogenic and the embryonic succession" and in the resultant principle that "the laws of embryonic development (ontogeny) are also the laws of geologic succession." This method and this principle Le Conte represented as "added" to biology by Agassiz. Holding such views of the importance and the date of origin of the recapitulation theory, Le Conte concluded that no one was reasonably entitled to believe in the transformation of species prior to the publication of the work of Agassiz; and hence that Chambers's evolutionism was a "baseless speculation." Le Conte's popular book has done much to form current ideas on this subject. But its author was misled by piety towards the memory of his greatest teacher into a serious neglect of chronology, in a matter where chronology is of the essence of the question at issue. Even if Agassiz be regarded as the originator of the doctrine of recapitulation, it must be remembered that he announced his evidences for that doctrine in his "Poissons du vieux grès rouge," 1842-44, and repeated them in popular form in his Lowell Lectures of 1848. And in point of fact, the doctrine and an important mass of evidence for it had then long been familiar; so that one finds Lyell, before 1835, arguing against the use of it as a proof of evolution. In the "Principles of Geology," he wrote:

Lyell's reply to this argument was brief and dogmatic: he fully admitted the facts, but denied the inference.

To the mind of Darwin the same sort of data presented a very different import.