| ←Subtitle not present 1859 1860 1861 Fresh-water
Productions
.
1866 1869 1872 |
| → I well remember, when first collecting in the fresh waters of Brazil, 1859 1860 1861 1866 1869 |
| When first collecting in the fresh waters of Brazil, I well remember 1872 |
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| → this power in 1859 1860 1861 1866 1869 |
| the wide ranging power of 1872 |
|
| → of ranging widely, though so unexpected, 1859 1860 1861 1866 1869 |
| OMIT 1872 |
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| → and 1859 1860 1861 1866 1869 |
| within their own countries; and 1872 |
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CHAPTER
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| GEOGRAPHICAL DISTRIBUTION—
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| Distribution of fresh-water productions— On the inhabitants of oceanic islands— Absence of Batrachians and of terrestrial Mammals— On the relation of the inhabitants of islands to those of the nearest mainland— On colonisation from the nearest source with subsequent modification— Summary of the last and present
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lakes and
are separated from each other by barriers of land, it might have been thought that fresh-water productions would not have ranged widely within the same country,
as the sea is apparently a still more
barrier, that they
have extended to distant countries. But the case is exactly the reverse. Not only have many fresh-water species, belonging to
different classes, an enormous range, but allied species prevail in a remarkable manner throughout the world.
→I well remember, when first collecting in the fresh waters of Brazil,
feeling much surprise at the similarity of the fresh-water insects, shells, &c., and at the dissimilarity of the surrounding terrestrial beings, compared with those of Britain. |
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| But
→this power in
fresh-water productions
→of ranging widely, though so unexpected,
can, I think, in most cases be explained by their having become fitted, in a manner highly useful to them, for short and frequent migrations from pond to pond, or from stream to
→and
liability to wide dispersal would follow from this capacity as an almost necessary consequence.
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