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See page in:
1859
1860
1861
1866
1869
1872

Compare with:
1859
1860
1861
1866
1869

→ resemble 1869 1872
are comparable with 1866
→ and if any wild species 1872
like that 1866 1869
→ same genus 1872
tapir or elephant. Now, if any wild species of the piggenus 1866
tapir or elephant. Now, if any wild species of the pig-genus 1869
→ had 1866 1872
in like manner had suddenly 1869
→ to find, after diligent search, 1869 1872
after diligent search, to find, in nearly allied forms, 1866
→ in nearly allied forms, and these alone bear on the question. 1872
resembling each other. 1866
in nearly allied forms, and these alone would bear on the question. 1869
→ their preservation would depend on unusually favourable circumstances. 1869 1872
they must be crossed with the ordinary form, and their character. will be transmitted in a modified state. 1866
↑ 1 blocks not present in 1859 1860 1861 1869 1872; present in 1866
If perpetuated in this crossed state, their preservation will be almost necessarily due to the modification being in some way beneficial to the animal under its then existing conditions of life; so that, even in this case, natural selection will come into play.
→ their abnormal character 1872
they 1869
→ be lost. 1872
lose their abnormal character. 1869
→ of the highest 1869 1872
highly 1859 1860 1861 1866
→ are often inherited, as must be familiar to every one; and they thus afford 1869 1872
afford 1859 1860
are often inherited, as must be familiar to every one; and thus they afford 1861 1866
→ act on and accumulate, 1866 1869 1872
accumulate, 1859 1860 1861
beautifully related to its complex conditions of life that it seems as improbable that any part should have been suddenly produced perfect, as that a complex machine should have been invented by man in a perfect state. Under domestication monstrosities
often
sometimes
occur which →resemble normal
structures.
structures
in
in
widely
widely
different
different
animals.
animals.
Thus pigs have
often
occasionally
been born with a sort of
proboscis
proboscis,
→and if any wild species of the →same genus had naturally possessed a proboscis, it might have been argued that this →had
suddenly appeared
appeared
as a monstrosity; but I have as yet
failed,
failed
→to find, after diligent search, cases of monstrosities
and of
resembling
normal structures →in nearly allied forms, and these alone bear on the question. If monstrous forms of this kind ever do appear in a state of nature and are capable of
propagation
reproduction
(which is not always the case), as they occur rarely and singly, →their preservation would depend on unusually favourable circumstances. ↑ They would, also, during the first and succeeding generations cross with the ordinary form, and thus →their abnormal character would almost inevitably →be lost. But I shall have to return in a future chapter to the preservation and perpetuation of
single or
single or
occasional variations.
Individual Differences.
The many slight differences which
frequently
....
appear in the offspring from the same parents, or which
may
it may
be presumed
to
....
have thus arisen, from being
frequently
....
observed in the individuals of the same species inhabiting the same confined locality, may be called individual differences. No one supposes that all the individuals of the same species are cast in the
very
....
same
mould.
actual mould.
These individual differences are →of the highest
important
importance
for us,
as
for
they →are often inherited, as must be familiar to every one; and they thus afford materials for natural selection to →act on and accumulate, in the same manner as man
can
....
accumulate
accumulates
in any given direction individual differences in his domesticated productions. These individual differences generally affect what naturalists consider unimportant parts; but I could show by a long catalogue of facts, that parts which must be called important, whether viewed under a physiological or classificatory point of view, sometimes vary in the individuals of the same species. I am convinced that the most experienced naturalist would be surprised at the number of the cases of variability, even in important parts of structure, which he could collect on good authority, as I have collected, during a course of years.
I
It
should be remembered that systematists are far from
pleased
being pleased
at finding variability in important characters, and that there are not many men who will laboriously examine internal and important organs, and compare them in many specimens of the