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Updated: June 23, 2025
The old red sandstone in which I hoed corn as a farm-boy dates back to Middle Palaeozoic time, or to the spring of the great geologic year, while the canon is of the late autumn. Could my native hills have replied to my mute questionings, they would have said: "We were old, old, and had passed through the canon stage long before the Grand Canon was born.
And this impulse implies initiative and choice, constituting an effort which we are not authorised by the facts to pronounce fatalistic: "A simple glance at the fossil species shows us that life could have done without evolution, or could have evolved only within very restricted limits, had it chosen the far easier path open to it of becoming cramped in its primitive forms; certain Foraminifera have not varied since the silurian period; the Lingulae, looking unmoved upon the innumerable revolutions which have upheaved our planet, are today what they were in the most distant times of the palaeozoic era."
I stated that "geographical provinces, or zones, may have been as distinctly marked in the Palaeozoic epoch as at present; and those seemingly sudden appearances of new genera and species, which we ascribe to new creation, may be simple results of migration." The opinion that the oldest known fossils are the earliest forms of life has no solid foundation.
New South Wales. Sandstone formation. Embedded pseudo-fragments of shale. Stratification. Current-cleavage. Great valleys. Van Diemen's Land. Palaeozoic formation. Newer formation with volcanic rocks. Travertin with leaves of extinct plants. Elevation of the land. New Zealand. King George's Sound. Superficial ferruginous beds. Superficial calcareous deposits, with casts of branches.
This group includes the large majority of existing species. But certain Jurassic and Triassic forms are now commonly admitted to be teleostean; and even some palaeozoic forms have thus been classed by one high authority.
Besides these four tests it may be said, in a general way, that volcanic rocks of Primary or Palaeozoic antiquity differ from those of the Secondary or Mesozoic age, and these again from the Tertiary and Recent.
If the thickness of more than 40,000 feet of sedimentary strata before alluded to in the Appalachians proves a preponderance of downward movements in Palaeozoic times in a district now forming the eastern border of North America, it also proves, as before hinted, the continued existence and waste of some neighbouring continent, probably formed of Laurentian rocks, and situated where the Atlantic now prevails.
In the several successive palaeozoic formations of Russia, Western Europe and North America, a similar parallelism in the forms of life has been observed by several authors: so it is, according to Lyell, with the several European and North American tertiary deposits.
The great Mississippi Valley was under water and above water time after time during the Palaeozoic period. The last great invasion of the land by the sea, and probably the greatest of all, seems to have been in Cretaceous times, at the end of the Mesozoic period. There were many minor invasions during Tertiary times, but none on so large a scale as this Cretaceous invasion.
The central plateau consists of ancient crystalline rocks with granites overlain by unfossiliferous sandstones and conglomerates considered to be of Palaeozoic age. The outcrops are largely hidden under laterite. The median zone is composed largely of crystalline rocks with granites and some Palaeozoic unfossiliferous rocks. The littoral zone contains the only fossiliferous strata.
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