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See page in:
1859
1860
1861
1866
1869
1872

Compare with:
1859
1860
1861
1866
1872

↑ 2 blocks not present in 1869; present in 1859 1860 1861 1866 1872
This view is hypothetical, but could be supported by some facts; and I can see no more abstract improbability in a tendency to produce any character being inherited for an endless number of generations, than in quite useless or rudimentary organs being, as we all know them to be, thus inherited. Indeed, we may sometimes observe a mere tendency to produce a rudiment inherited: for instance, in the common snapdragon (Antirrhinum) a rudiment of a fifth stamen so often appears, that this plant must have an inherited tendency to produce it.
→ on our theory, to be 1869
on my theory, to have 1859 1860 1861 1866
to be 1872
→ the varieties of two or more 1866 1869 1872
a variety of one 1859 1860 1861
→ each other, or that a variety of some one species would resemble in certain 1869
in some of its 1859 1860 1861
each other, or that a variety of one species would resemble in some of its 1866
each other, or that a variety of one species would resemble in certain 1872
→ and distinct species, — 1866 1869
species; 1859 1860 1861
and distinct species,— 1872
→ according to our 1869 1872
on my 1859 1860 1861 1866
→ thus gained 1859 1860 1861 1866 1869
exclu- sively due to analogous variation 1872
→ be governed by 1859 1860 1861 1866 1869
have been determined through 1872
→ the conditions of life. 1869
OMIT 1872
a similar inherited constitution. 1859 1860 1861 1866
→ long lost ancestral 1869
lost ancestral 1859 1860 1861 1866
long lost 1872
→ exact character of the 1859 1860 1861 1866 1869
OMIT 1872
→ could not distinguish these two cases: if, 1859 1860 1861 1866 1869
cannot distinguish between reversionary and analogous characters. If, 1872
→ it does not appear probable would 1859 1860 1861 1866 1869
would not probably have 1872
→ the several marks 1869 1872
marks 1859 1860 1861 1866
→ distinct breeds of distinct colours 1869
distinct breeds of diverse colours 1859 1860 1861 1866
differently coloured breeds 1872
useless or rudimentary organs being thus transmitted. A mere tendency to produce a rudiment is indeed sometimes inherited. ↑
As all the species of the same genus are
supposed
supposed,
→on our theory, to be descended from a common
parent,
progenitor,
it might be expected that they would occasionally vary in an analogous manner; so that →the varieties of two or more species would resemble →each other, or that a variety of some one species would resemble in certain characters another →and distinct species, — this other species
being,
being
→according to our
view,
view
only a well-marked and permanent variety. But characters →thus gained would probably be of an unimportant nature, for the
preservation
presence
of all
functionally important
important
characters will →be governed by natural selection, in accordance with the
diverse
different
habits of the
species.
species,
and
and
will
will
not
not
be
be
left
left
to
to
the
the
mutual
mutual
action
action
of
of
the
the
conditions
nature
nature
of
of
life
the organism
the organism
and
and
of
of
→the conditions of life. It might further be expected that the species of the same genus would occasionally exhibit reversions to →long lost ancestral characters. As, however, we
do not
never
know the →exact character of the common ancestor of
any natural
a
group,
natural group,
we →could not distinguish these two cases: if, for instance, we did not know that the
rock- pigeon
parent rock-pigeon
rock-pigeon
was not feather-footed or turn-crowned, we could not have told, whether
such
these
characters in our domestic breeds were reversions or only analogous variations; but we might have inferred that the
blueness
blue colour
was a case of
reversion,
reversion
from the number of the markings, which are correlated with
the blue
this
tint, and which →it does not appear probable would all
appeared
appear
together from simple variation. More especially we might have inferred this, from the blue colour and →the several marks so often appearing when →distinct breeds of distinct colours are crossed. Hence,
though
although
under nature it must generally be left doubtful, what cases