| → here give a single instance of one of the cases of difficulty. 1859 1860 1861 1866 |
| specify one such difficult case. 1869 |
| specify one difficult case. 1872 |
|
| → elsewhere. 1859 1860 1861 1866 |
| elsewhere,— striking instances of which have been given by Dr. A. A. Gould in relation to the Pacific. 1869 1872 |
|
| → be, on my view, 1859 1860 1861 1866 |
| be, according to our view, 1869 |
| be 1872 |
|
| → occasionally crawl on and 1859 1860 1861 1866 |
| sometimes 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 |
|
| ↑ 6 blocks not present in 1859 1860 1861; present in 1866 1869 1872 |
| During this length of time it
might have been carried by a marine 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 it
recovered and crawled away.
Baron Aucapitaine has recently
tried similar 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
of fifty-four specimens belonging to four species
of Helix tried by Aucapitaine, recovered.
|
|
| ↑ 1 blocks not present in 1859 1860 1861 1866; present in 1869 1872 |
| It is, however, not at all probable that land-shells have often been thus transported; the feet of birds is
a more probable method.
|
|
| ←Subtitle not present 1859 1860 1861 On
the
Relations
of
the
Inhabitants
of
Islands
to
those
of
the
nearest
Mainland
.
1869 1872 |
| → in regard to the inhabitants of islands, is their affinity 1859 1860 1861 |
| in regard to islands, is the affinity 1866 |
| is the affinity of the species which inhabit islands 1869 1872 |
|
| → to 1859 1860 1861 1869 1872 |
| of their inhabitants to 1866 |
|
| → 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 |
|
