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See page in:
1859
1860
1861
1866
1869
1872

Compare with:
1859
1860
1861
1866
1872

→ organs of such wonderful structure, 1859 1860 1861 1866 1869
an organ so wonderful 1872
→ so marvellous an instinct as that 1859 1860 1861 1866 1869
the instinct 1872
→ which has 1860 1861 1866 1869
which have 1859
and which has 1872
→ shall be here discussed—Instinct 1866 1869
shall be here discussed— Instinct 1859 1860 1861
will here be discussed; some miscellaneous objections in the following chapter; Instinct 1872
→ separate 1859 1860 1861 1866 1869
the two succeeding 1872
→ OMIT 1866 1869 1872
will, as we have seen, 1859 1860 1861
→ hand. 1859 1860 1861 1866 1869
hand. Hence, if we look at each species as descended from some unknown form, both the parent and all the transitional varieties will generally have been exterminated by the very process of the formation and perfection of the new form. 1872
↑ 2 blocks not present in 1869 1872; present in 1859 1860 1861 1866
These contingencies will concur only rarely, and after enormously long intervals. Whilst the bed of the sea is stationary or is rising, or when very little sediment is being deposited, there will be blanks in our geological history.
→ imperfectly made, and 1869 1872
made 1859 1860 1861 1866
→organs of such wonderful structure, as the
eye?
eye,
of
of
which
which
we
we
hardly
hardly
as
as
yet
yet
fully
fully
understand
understand
the
the
inimitable
inimitable
perfection?
perfection?
Thirdly, can instincts be acquired and modified through natural selection? What shall we say to →so marvellous an instinct as that which leads the bee to make cells, →which has practically anticipated the discoveries of profound mathematicians?
Fourthly, how can we account for species, when crossed, being sterile and producing sterile offspring, whereas, when varieties are crossed, their fertility is unimpaired?
The two first heads →shall be here discussed—Instinct and Hybridism in →separate chapters.
On
On
the
the
absence
Absence
Absence
or
or
rarity
Rarity
Rarity
of
of
transitional
Transitional
Transitional
varieties .—
varieties. —
Varieties.
Varieties .—
Varieties.
As natural selection acts solely by the preservation of profitable modifications, each new form will tend in a fully-stocked country to take the place of, and finally to exterminate, its own less improved
parent or
parent-form and
other less-favoured forms with which it comes into competition. Thus extinction and natural selection →OMIT go hand in →hand. Hence, if we look at each species as descended from some other unknown form, both the parent and all the transitional varieties will generally have been exterminated by the very process of
formation
the formation
and perfection of the new form.
But, as by this theory innumerable transitional forms must have existed, why do we not find them embedded in countless numbers in the crust of the
earth?
earth.
It will be
much
....
more convenient to discuss this question in the chapter on the Imperfection of the
geological
Geological
record;
Record;
and I will here only state that I believe the answer mainly lies in the record being incomparably less perfect than is generally
supposed;
supposed.
the
....
imperfection
....
of
....
the
....
record
....
being
....
chiefly
....
due
....
to
....
organic
....
beings
....
not
....
inhabiting
....
profound
....
depths
....
of
....
the
....
sea,
....
and
....
to
....
their
....
remains
....
being
....
embedded
....
and
....
preserved
....
to
....
a
....
future
....
age
....
only
....
in
....
masses
....
of
....
sediment
....
sufficiently
....
thick
....
and
....
extensive
....
to
....
withstand
....
an
....
enormous
....
amount
....
of
....
future
....
degradation;
....
and
....
such
....
fossiliferous
....
masses
....
can
....
be
....
accumulated
....
only
....
where
....
much
....
sediment
....
is
....
deposited
....
on
....
the
....
shallow
....
bed
....
of
....
the
....
sea,
....
whilst
....
it
....
slowly
....
subsides.
....
↑ The crust of the earth is a vast museum; but the natural collections have been →imperfectly made, and only at
intervals
long intervals
of
time
time.
immensely
....
remote.
....