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See page in:
1859
1860
1861
1866
1869
1872

Compare with:
1859
1860
1861
1866
1872

→ (either from reversion or from analogous variation) which already are present in 1869
(either from reversion or from analogous variation) which already occur in some 1859 1860 1861 1866
which are already present in 1872
→ A considerable part of the 1859 1860 1861 1866 1869
The 1872
→ recognising in our systematic works a variable species, is 1866 1869
recognising a variable species in our systematic works, is 1859 1860 1861
distinguishing variable species is largely 1872
→ OMIT 1869 1872
some of the 1859 1860 1861 1866
→ can only doubtfully be 1869 1872
must be doubtfully 1859 1860 1861 1866
→ OMIT 1869 1872
either varieties or 1859 1860 1861 1866
→ forms 1859 1860 1861 1866 1869
closely allied forms 1872
→ is 1859 1860 1861 1866 1869
of analogous variations is 1872
→ of an important and generally uniform nature occasionally varying 1869
of an important and uniform nature occasionally varying 1859 1860 1861 1866
which are generally constant in character, but which occasionally vary 1872
→ character of the 1859 1860 1861 1866 1869
OMIT 1872
↑ 1 blocks not present in 1869; present in 1859 1860 1861 1866 1872
It has also been asserted that the stripe on each shoulder is sometimes double.
→ stripe on the shoulder is sometimes double and is 1866 1869
shoulder-stripe is certainly 1859 1860 1861
stripe on the shoulder is sometimes double, and is 1872
are reversions to
an anciently
formerly
a formerly
existing
characters,
character,
and what are new but analogous variations, yet we ought, on
my
our
theory, sometimes to find the varying offspring of a species assuming characters →(either from reversion or from analogous variation) which already are present in other members of the same group. And this undoubtedly is the
case
case.
in
....
nature.
....
→A considerable part of the difficulty in →recognising in our systematic works a variable species, is due to
the
its
varieties mocking, as it were, →OMIT other species of the same genus. A considerable catalogue, also, could be given of forms intermediate between two other forms, which themselves →can only doubtfully be ranked as →OMIT species; and this shows, unless all these →forms be considered as independently created species, that
they
the
have
one
in varying
has
has
assumed some of the characters of the
others.
other,
so
so
as
as
to
to
produce
produce
the
the
intermediate
intermediate
form.
forms.
forms.
But the best evidence →is afforded by parts or organs →of an important and generally uniform nature occasionally varying so as to
resemble,
acquire,
in some degree, the →character of the same part or organ in an allied species. I have collected a long list of such cases; but here, as before, I lie under
a
the
great disadvantage
in
of
not being able to give them. I can only repeat that such cases certainly
do
do
occur, and seem to me very remarkable.
I will, however, give one curious and complex case, not indeed as affecting any important character, but from occurring in several species of the same genus, partly under domestication and partly under nature. It is a case
apparently
almost certainly
of reversion. The ass
not rarely
sometimes
has very distinct transverse bars on its legs, like those on the legs of
a
the
zebra.
zebra:
it
it
has
has
been
been
asserted
asserted
that
that
these
these
are
are
plainest
plainest
in
in
the
the
foal,
foal,
and
and,
and,
from
from
inquiries
inquiries
which
which
I
I
have
have
made,
made,
I
I
believe
believe
this
this
to
to
be
be
true.
true.
↑ The →stripe on the shoulder is sometimes double and is very variable in length and outline.