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See page in:
1859
1860
1861
1866
1869
1872

Compare with:
1859
1860
1861
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1869

→ being closely related, though ranked as distinct species, 1869 1872
though ranked as distinct species, being closely related, 1859 1860 1861 1866
→ in any two 1866 1869 1872
two 1859 1860 1861
→ compared with Living Forms . 1872
Forms .— 1859 1860
compared with Living Forms. — 1861
compared with Living Forms. 1866
compared with Living Forms. 1869
→ tend 1866 1869 1872
constantly tend thus 1861
↑ 2 blocks not present in 1861 1866 1869 1872; present in 1859 1860
There has been much discussion whether recent forms are more highly developed than ancient. I will not here enter on this subject, for naturalists have not as yet defined to each other's satisfaction what is meant by high and low forms.
↑ 1 blocks not present in 1859 1860 1861 1866 1869 1872; present in
→ and it seems that this answer must be admitted as true, though difficult of proof. 1872
but in my judgment I can, after having read the discussions on this subject by Lyell, and Hooker's views in regard to plants, concur only to a limited extent. 1861
but in my judgment I cannot, after having read the discussions on this subject by Lyell, Bronn, and Hooker, look at this conclusion as fully proved, though highly probable. 1866
and I suppose that the answer must be admitted as true, though difficult of full proof. 1869
→ OMIT 1869 1872
or to the general belief that species in the course of time change, 1866
On the theory of descent, the full meaning of the
fact of
....
fossil remains from closely consecutive
formations,
formations
→being closely related, though ranked as distinct species, is obvious. As the accumulation of each formation has often been interrupted, and as long blank intervals have intervened between successive formations, we ought not to expect to find, as I attempted to show in the last chapter, in any one or →in any two
formations
formations,
all the intermediate varieties between the species which appeared at the commencement and close of these
periods;
periods:
but we ought to find after intervals, very long as measured by years, but only moderately long as measured geologically, closely allied forms, or, as they have been called by some authors, representative species; and these
we assuredly
assuredly we
do find. We find, in short, such evidence of the slow and scarcely sensible
mutation
mutations
of specific forms, as we have
a just
the
right to
expect
expect.
to
....
find.
....
On
On
the
the
state
State
State
of
of
Development
Development
of
of
Ancient
Ancient
→ compared with Living Forms .
We have seen in the fourth chapter that the degree of differentiation and specialisation of the parts
of
in
all
....
organic beings, when
come to
arrived at
maturity, is the best standard, as yet suggested, of their degree of perfection or highness. We have also seen
that
that,
as the specialisation of parts
and organs
....
is an advantage to each being, so natural selection will →tend to render the organisation of each being more specialised and perfect, and in this sense higher; not but that it may
and will
....
leave many creatures with simple and unimproved structures fitted for simple conditions of life, and in some cases will even degrade or simplify the organisation, yet leaving such degraded beings better fitted for their new walks of life. ↑ ↑ In another and more general manner, new species
will
....
become superior to their predecessors; for they
will
....
have to beat in the struggle for life all the older
forms
forms,
with which they come into close competition. We may therefore conclude that if under a nearly similar climate the eocene inhabitants of the world could be put into competition with the existing inhabitants, the former would be beaten and exterminated by the latter, as would the secondary by the eocene, and the palæozoic by the secondary forms. So that by this fundamental test of victory in the battle for life, as well as by the standard of the specialisation of organs, modern forms
ought
ought,
on the theory of natural
selection
selection,
to stand higher than ancient forms. Is this the case? A large majority of palæontologists would
certainly
....
answer in the affirmative; →and it seems that this answer must be admitted as true, though difficult of proof.
It is no valid objection to this
conclusion
conclusion,
→OMIT