Periods.
Distinct Provinces of indigenous Species.
Great Extent of single Provinces.
Similar Laws prevailed at successive Geological Periods.
Relative Importance of mineral and palaeontological Characters.
Test of Age by included Fragments.
Frequent Absence of Strata of intervening Periods.
Tabular Views of fossiliferous Strata.


CHAPTER IX.

CLASSIFICATION OF TERTIARY FORMATIONS.

Order of Succession of Sedimentary Formations.
Frequent Unconformability of Strata.
Imperfection of the Record.
Defectiveness of the Monuments greater in Proportion to their Antiquity.
Reasons for studying the newer Groups first.
Nomenclature of Formations.
Detached Tertiary Formations scattered over Europe.
Value of the Shell-bearing Mollusca in Classification.
Classification of Tertiary Strata.
Eocene, Miocene, and Pliocene Terms explained.


CHAPTER X.

RECENT AND POST-PLIOCENE PERIODS.