While making this admission in relation to the vegetation of these older rocks, I must protest against the practice of completing the record of life forms, by filling in particular groups without any authority except the writer's impression of an adopted hypothesis, and then basing arguments on these assumptions in support of the hypothesis which created them. So completely has
+----------------------------------------------------+ | Post Tertiary.| | +----------------------------------------------------+ Tertiary. { | Pliocene. | | +----------------------------------------------------+ { | Miocene. | | +----------------------------------------------------+ { | Eocene. | | +----------------------------------------------------+ Secondary. { | Chalk. | Dicotyledons (Apetalæ, Polypetalæ, | { | | Sympetalæ). | +----------------------------------------------------+ { | Oolite. | | +----------------------------------------------------+ { | Trias. | | +----------------------------------------------------+ | | | { | Permian. | | +----------------------------------------------------+ { | Carboniferous.| Monocotyledons. | +----------------------------------------------------+ { | | | { | Devonian, or | Clubmosses, Horsetails, Ferns, | { | Old Red | Gymnosperms. | { | Sandstone. | | +----------------------------------------------------+ Primary. { | Silurian. | } Cellular Cryptogams. | { | Cambrian. | } | +----------------------------------------------------+ { | Huronian. | } Indications of Plants, | { | Laurentian. | } not determinable. | +===================+================================+ | AZOIC. | |
phylogenetic [or racial] evolution become the creed of some leading naturalists that they unwittingly proceed in this manifestly unphilosophical method. But it is a first axiom, though one often forgotten, in this as in every scientific enquiry, that no step can be made in advance which is not based on fact.
After this initial stage, the story becomes much clearer, and at the same time less easy to reconcile with evolutionary requirements.
Instead of making their appearance singly and successively, and passing imperceptibly one into another, all three groups of Vascular Cryptogams, and the Gymnosperms into the bargain, come on the stage together, in the Devonian strata; and Monocotyledons in the lower Carboniferous immediately following. There is no trace whatever of the development of any of these forms from the earlier cellular cryptogams: