sufficient care, as the important discoveries made every year in Europe prove. No organism wholly soft can be preserved. Shells and bones
will will 1859 1860 1861 1866 1869 | will 1872 |
decay and disappear when left on the bottom of the sea, where sediment is not
accumulating. accumulating. 1859 1860 1861 1869 1872 | accumulation. 1866 |
I believe we are continually taking a most I believe we are continually taking a most 1859 1860 1861 1866 |
I believe we often take an 1869 |
We probably take a quite 1872 |
erroneous view, when we
tacitly admit to ourselves tacitly admit to ourselves 1859 1860 1861 1866 1869 |
assume 1872 |
that sediment is being deposited over nearly the whole bed of the sea, at a rate sufficiently quick to embed and preserve fossil remains. Throughout an enormously large proportion of the ocean, the bright blue tint of the water bespeaks its purity. The many cases on record of a formation conformably covered, after an
enormous enormous 1859 1860 1861 1866 | immense 1869 1872 |
interval of time, by another and later formation, without the underlying bed having suffered in the interval any wear and
tear, tear, 1859 1860 1861 1866 1872 | tear 1869 |
seem explicable only on the view of the bottom of the sea not rarely lying for ages in an unaltered condition. The remains which do become embedded, if in sand or gravel,
will will 1859 1860 1861 1866 1869 | will, 1872 |
when the beds are
upraised upraised 1859 1860 1861 1866 1869 | upraised, 1872 |
generally be dissolved by the percolation of
rain-water. rain-water. 1859 1860 |
rain-water charged with carbonic acid. 1861 1866 1869 1872 |
I suspect that but few I suspect that but few 1859 1860 |
Some 1861 1866 1869 1872 |
of the
very very 1859 1860 | very 1861 1866 1869 1872 |
many
animals animals 1859 1860 |
kinds of animals 1861 1866 1869 1872 |
which live on the beach between high and low
watermark watermark 1859 1860 | water mark 1861 1866 1869 1872 |
are are 1859 1860 |
seem to be rarely 1861 1866 1869 1872 |
preserved. For instance, the several species of the Chthamalinæ (a
sub-family sub-family 1859 1861 1866 1869 1872 | subfamily 1860 |
of sessile cirripedes) coat the rocks all over the world in infinite numbers: they are all strictly littoral, with the exception of a single Mediterranean species, which inhabits deep
water water 1859 1860 | water, 1861 1866 1869 1872 |
and
has has 1859 1860 1861 1866 | this has 1869 1872 |
been found fossil in Sicily, whereas not one other species has hitherto been found in any tertiary
formation: formation: 1859 1860 1861 1866 1869 | formation; 1872 |
yet it is
now now 1859 1860 1861 1866 1869 | now 1872 |
known that the genus Chthamalus existed during the
chalk chalk 1859 1860 1861 | Chalk 1866 1869 1872 |
period. The molluscan genus Chiton offers a partially analogous case. ↑1 blocks not present in 1859 1860 1861 1866; present in 1869 1872 | Lastly, many great deposits requiring a vast length of time for their accumulation, are entirely destitute of organic remains, without our being able to assign any reason: one of the most striking instances is that of the Flysch formation, which consists of shale and sandstone, several thousand, occasionally even six thousand feet, in thickness, and extending for at least 300 miles from Vienna to Switzerland; and although this great mass has been most carefully searched, no fossils, except a few vegetable remains, have been found.
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