of any one or more
species
if we were to examine them
ever
so closely, unless we likewise
possessed many
of the intermediate links
between their past or parent and present states; and these many links we could hardly ever
expect to discover, owing to the imperfection of the geological record. If two or three, or even more linking forms were discovered, they would simply be ranked as
so many new species, more especially if found in different geological sub-stages, let their differences be ever so slight. Numerous existing doubtful forms could be named which are probably varieties; but who will pretend that in future ages so many fossil links will be discovered, that naturalists will be able to
decide, decide, 1859 1860 1861 | decide 1866 1869 1872 |
on the common view, whether or not on the common view, whether or not 1859 1860 1861 |
whether or not on the common view 1866 |
whether or not 1869 1872 |
these doubtful forms are
varieties? ↑1 blocks not present in 1861 1866 1869 1872; present in 1859 1860 | As long as most of the links between any two species are unknown, if any one link or intermediate variety be discovered, it will simply be classed as another and distinct species.
|
Only a small portion of the world has been
geologically geologically 1859 1860 1861 1869 1872 | geological 1866 |
explored. Only organic beings of certain classes can be preserved in a fossil condition, at least in any great number. ↑1 blocks not present in 1859 1860 1861; present in 1866 1869 1872 | Many species when once formed never undergo any further change,
but become extinct without leaving modified descendants; and the periods, during which species have undergone modification, though long as measured by years, have probably been short in comparison with the periods during which they have
retained the same form.
|
Widely Widely 1859 1860 1861 |
It is the dominant and widely 1866 1869 1872 |
ranging species
vary vary 1859 1860 1861 |
which vary most frequently and vary 1866 1869 1872 |
most, and varieties are often at first local,—
both causes rendering the discovery of intermediate links
less less 1859 1860 1861 |
in any one formation less 1866 1869 1872 |
likely. Local varieties will not spread into other and distant regions until they are considerably modified and im-
proved;
and when they do
spread, if
discovered in a geological formation, they will
appear as if suddenly created there, and will be simply classed as new species. Most formations have
been, been, 1861 | been 1859 1860 1866 1869 1872 |
intermittent in their accumulation; and their
duration, duration, 1859 1860 1861 | duration 1866 1869 1872 |
I am inclined to believe, has I am inclined to believe, has 1859 1860 1861 |
has probably 1866 1869 1872 |
been shorter than the average
|