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See page in:
1859
1860
1861
1866
1869
1872

Compare with:
1859
1860
1861
1869
1872

→ of these shells was 1859 1860 1861 1866
shell, 1869 1872
→ it had 1859 1860 1861 1866
having been thus treated and 1869 1872
→ running at an average rate, 1866
of average swiftness, 1869 1872
→ Helix pomatia 1866
the Helix pomatia resisted 1872
OMIT 1869
→ resisted the 1866
the Helix pomatia resisted the 1869
the 1872
↑ 1 blocks not present in 1866 1869 1872; present in 1859 1860 1861
As this species has a thick calcareous operculum, I removed it, and when it had formed a new membranous one, I immersed it for fourteen days in sea-water, and it recovered and crawled away: but more experiments are wanted on this head.
→ in regard to islands, is the affinity 1866
in regard to the inhabitants of islands, is their affinity 1859 1860 1861
is the affinity of the species which inhabit islands 1869 1872
→ of their inhabitants to 1866
to 1859 1860 1861 1869 1872
→ I will give only one, that of the 1859 1860 1861 1866
The 1869 1872
→ between 1859 1860 1861 1866
lies at the distance of between 1869 1872
membranous diaphragm over the mouth of the shell, might be floated in chinks of drifted timber across moderately wide arms of the sea. And I
find
found
that several species
did
did
in this state
withstood
withstand
uninjured an immersion in sea-water during seven days: one →of these shells was the Helix pomatia,
and
and
after →it had again
hybernating
hybernated
was
I
put
it in
into
it into
sea-water for twenty days, and
it
it
perfectly recovered. During this length of time
the shell
it
might have been carried by a marine
current
current,
→running at an average rate, to a distance of 660 geographical miles. As this Helix has a thick calcareous operculum, I removed it, and when it had formed a new membranous one, I again immersed it for fourteen days in sea-water, and
again it
it
recovered and crawled away. Baron Aucapitaine has
since
recently
tried similar
experi- ments:
experiments:
he placed 100 land-shells, belonging to ten species, in a box pierced with holes, and immersed it for a fortnight in the sea. Out of the hundred shells, twenty-seven recovered. The presence of an operculum seems to have been of importance, as out of twelve specimens of Cyclostoma elegans, which is thus furnished, eleven revived. It is remarkable, seeing how well →Helix pomatia with me →resisted the salt-water, that not one
out
out
of fifty-four specimens belonging to four
other species
species
of Helix tried by Aucapitaine, recovered. ↑
On the Relations of the Inhabitants of Islands to those of the nearest Mainland .
The most striking and important fact for us →in regard to islands, is the affinity →of their inhabitants to those of the nearest mainland, without being actually the
same.
same
species.
species.
Numerous instances could be
given.
given
of
of
this
this
fact.
law.
law.
→I will give only one, that of the Galapagos Archipelago, situated under the equator, →between 500 and 600 miles from the shores of South America. Here