2. Cretaceous { from the Maestricht Chalk to the Lower { Greensand inclusive. 3. Oolitic from the Wealden to the Lias inclusive. 4. Triassic { including the Keuper, Muschelkalk, and { Bunter Sandstein of the Germans. 5. Permian, Carboniferous, } including Magnesian Limestone (Zechstein), and Devonian } Coal, Mountain Limestone, and } Old Red sandstone. 6. Silurian and Cambrian } from the Upper Silurian to the oldest } fossiliferous rocks inclusive. FOOTNOTES: [103-A] For tertiary, Sir H. De la Beche has used the term "supracretaceous," a name implying that the strata so called are superior in position to the chalk. [103-B] Professor Phillips has adopted these terms: Cainozoic, from +kainos+, _cainos_, recent, and +zoon+, _zoon_, animal; Mesozoic, from +mesos+, _mesos_, middle, &c.; Paleozoic, from +palaios+, _palaios_, ancient, &c. [103-C] Palaeontology is the science which treats of fossil remains, both animal and vegetable. Etym. +palaios+, _palaios_, ancient, +onta+, _onta_, beings, and +logos+, _logos_, a discourse. CHAPTER X. CLASSIFICATION OF TERTIARY FORMATIONS.--POST-PLIOCENE GROUP. General principles of classification of tertiary strata--Detached formations scattered over Europe--Strata of Paris and London--More modern groups--Peculiar difficulties in determining the chronology of tertiary formations--Increasing proportion of living species of shells in strata of newer origin--Terms Eocene, Miocene, and Pliocene--Post-Pliocene strata--Recent or human period--Older Post-Pliocene formations of Naples, Uddevalla, and Norway--Ancient upraised delta of the Mississippi--Loess of the Rhine. Before describing the most modern of the sets of strata enumerated in the tables given at the end of the last chapter, it will be necessary to say something generally of the mode of classifying the formations called tertiary. The name of tertiary has been given to them, because they are all posterior in date to the rocks termed "secondary," of which the chalk constitutes the newest group. These tertiary strata were at first confounded, as before stated, p. 91., with the superficial alluviums of Europe; and it was long before their real extent and thickness, and the various ages to which they belong, were fully recognized. They were observed to occur in patches, some of freshwater, others of marine origin, their geographical area being usually small as compared to the secondary formations, and their position often suggesting the idea of their having been deposited in different bays, lakes, estuaries, or inland seas, after a large portion of the space now occupied by Europe had already been converted into dry land.