| → of time, namely, 1861 1866 1869 1872 |
| namely, 1859 1860 |
|
| → so that here again we have undoubted evidence of change, though not strictly of variation, 1861 1866 |
| but to this subject I shall have to return 1859 1860 |
| so that here again we have undoubted evidence of change 1869 1872 |
|
| → direction required by my theory; but to this latter subject I shall have to return in the following 1861 1866 |
| following 1859 1860 |
| direction required by the theory; but to this latter subject I shall have to return in the following 1869 |
| direction required by the theory; but to this latter subject I shall return in the following 1872 |
|
| → OMIT 1866 1869 1872 |
| One other consideration is worth notice: 1859 1860 1861 |
|
| → highly probable that 1861 1866 |
| probably 1859 1860 |
| probable 1869 1872 |
|
| → those which have 1859 1860 1861 1866 |
| that those which have 1869 |
| that those which 1872 |
|
| → species have been undergoing 1866 |
| each species underwent 1869 1872 |
|
|
to rather wider
→of time, namely,
to distinct but consecutive stages of the same great formation, we find that the embedded fossils, though
universally ranked as specifically different, yet are far more closely
to each other than are the species found in more widely separated formations;
→so that here again we have undoubted evidence of change, though not strictly of variation,
in the
→direction required by my theory; but to this latter subject I shall have to return in the following
chapter. |
|
|
→OMIT
animals and plants that
propagate rapidly and
not
there is reason to suspect, as we have formerly seen, that their varieties are generally at first local; and that such local varieties do not spread widely and supplant their parent-forms until they have been modified and perfected in some considerable degree. According to this view, the chance of discovering in a formation in any one country all the early stages of transition between any two
is small, for the successive changes are supposed to have been local or confined to some one spot. Most marine animals have a wide range; and we have seen that with plants it is those which have the widest range, that oftenest present varieties; so
with shells and other marine animals, it is
→highly probable that
→those which have
had the widest range, far exceeding the limits of the known geological formations of Europe,
have oftenest given rise, first to local varieties and ultimately to new species; and this again would greatly lessen the chance of our being able to trace the stages of transition in any
geological formation. |
|
| It is a more important consideration,
leading to the same result, as lately insisted on by Dr. Falconer, namely, that the
during which
→species have been undergoing
modification, though
long as
|
