By this means the German, French, and English geologists have determined the succession of strata throughout a great part of Europe, and have adopted pretty generally the following groups, almost all of which have their representatives in the British Islands. _Groups of Fossiliferous Strata observed in Western Europe, arranged in what is termed a descending Series, or beginning with the newest._ (_See a more detailed Tabular view_, pp. 360. 365.) 1. Post-Pliocene, including those of the Recent, or human period. 2. Newer Pliocene, or Pleistocene. } 3. Older Pliocene. } Tertiary, Supracretaceous[103-A], 4. Miocene. } or Cainozoic.[103-B] 5. Eocene. } 6. Chalk. } 7. Greensand. } 8. Wealden. } 9. Upper Oolite. } Secondary, or Mesozoic.[103-B] 10. Middle Oolite. } 11. Lower Oolite. } 12. Lias. } 13. Trias. } 14. Permian. } 15. Coal. } 16. Old Red sandstone, or Devonian. } Primary fossiliferous, 17. Upper Silurian. } or paleozoic.[103-B] 18. Lower Silurian. } 19. Cambrian and older fossiliferous strata. } It is not pretended that the three principal sections in the above table, called primary, secondary, and tertiary, are of equivalent importance, or that the eighteen subordinate groups comprise monuments relating to equal portions of past time, or of the earth's history. But we can assert that they each relate to successive periods, during which certain animals and plants, for the most part peculiar to their respective eras, have flourished, and during which different kinds of sediment were deposited in the space now occupied by Europe. If we were disposed, on palaeontological grounds[103-C], to divide the entire fossiliferous series into a few groups less numerous than those in the above table, and more nearly co-ordinate in value than the sections called primary, secondary, and tertiary, we might, perhaps, adopt the six groups or periods given in the next table (p. 104.). At the same time, I may observe, that, in the present state of the science, when we have not yet compared the evidence derivable from all classes of fossils, not even those most generally distributed, such as shells, corals, and fish, such generalizations are premature, and can only be regarded as conjectural or provisional schemes for the founding of large natural groups. _Fossiliferous Strata of Western Europe divided into Six Groups._ 1. Post Pliocene and } from the Post-Pliocene to the Tertiary } Eocene inclusive.