| → and then less differentiated vertebrate 1866 |
| vertebrate 1859 1860 1861 |
| and at that time less differentiated vertebrate 1869 1872 |
|
| → as in that of 1859 1860 1861 1866 |
| as with 1869 |
| for instance 1872 |
|
| → and only partially 1866 1869 1872 |
| but 1859 1860 1861 |
|
| → from other groups, as all would be blended together by steps as fine as those between existing varieties, nevertheless 1866 |
| from other groups, as all would blend together by steps as fine as those between the finest existing varieties, nevertheless 1859 1860 |
| from other groups, as all would blend together by steps as fine as those between existing varieties, nevertheless 1861 |
| still 1869 1872 |
|
| → Every intermediate link between these eleven genera and their primordial parent, and every intermediate 1859 1860 1861 1866 |
| with every 1869 1872 |
|
| → of their descendants, may be supposed to be 1859 1860 1861 1866 |
| OMIT 1869 1872 |
|
| → to be as fine as 1859 1860 1861 1866 |
| not greater than 1869 1872 |
|
| → or these parents from their ancient and unknown progenitor. 1859 1860 1861 1866 |
| and descendants. 1869 1872 |
|
|
the intervals between the several groups in each class. We may thus account
for the distinctness of whole classes from each other— for instance, of birds from all other vertebrate animals— by the belief that many ancient forms of life have been utterly lost, through which the early progenitors of birds were formerly connected with the early progenitors of the other
→and then less differentiated vertebrate
classes. There has been
extinction of the forms of life which once connected fishes with batrachians. There has been still less
some
classes,
→as in that of
the Crustacea, for here the most
diverse forms are still
together by
→and only partially
of affinities. Extinction has only
it has by no means made them; for if every form which has ever lived on this earth were suddenly to reappear, though it would be quite impossible to give definitions by which each group could be
→from other groups, as all would be blended together by steps as fine as those between existing varieties, nevertheless
a natural classification, or at least a natural arrangement, would be possible. We shall see this by turning to the
the letters, A to L, may represent eleven Silurian genera, some of which have produced large groups of modified
→Every intermediate link between these eleven genera and their primordial parent, and every intermediate
link in each branch and sub-branch
→of their descendants, may be supposed to be
still alive; and the links
→to be as fine as
those between
varieties. In this case it would be quite impossible to give
by which the several members of the several groups could be distinguished from their more immediate
→or these parents from their ancient and unknown progenitor. Yet the
arrangement in the
|
