Note 5 — THE TESTIMONY OF THE ROCKS.

The horizontal lines of the diagram here indicate, as in Fig. 1, the divisions of the several geologic systems; the vertical lines represent the leading divisions and classes of animals, and, as shown by the formations in which their earliest known remains occur, the probable period of their first appearance in creation; while the double line of text below exhibits the complete correspondence which obtains between their occurrence, in nature and the Cuvierian arrangement. The line representative of the Radiata ought perhaps to have been elevated a little higher than either of its two neighbors.