Many facts could be given showing how generally
soil is charged with seeds. For instance, Professor Newton sent me the leg
of a red-legged partridge (Caccabis rufa) which had been wounded and could
not fly, with a ball of hard earth adhering to it, and weighing six and a
half ounces. The earth had been kept for three years, but when broken,
watered and placed under a bell glass, no less than eighty-two plants
sprung from it: these consisted of twelve monocotyledons, including the
common oat, and at least one kind of grass, and of seventy dicotyledons,
which consisted, judging from the young leaves, of at least three distinct
species. With such facts before us, can we doubt that the many birds which
are annually blown by gales across great spaces of ocean, and which
annually migrate--for instance, the millions of quails across the
Mediterranean--must occasionally transport a few seeds embedded in dirt
adhering to their feet or beaks? But I shall have to recur to this
subject.
As icebergs are known to be sometimes loaded with earth and stones, and
have even carried brushwood, bones, and the nest of a land-bird, it can
hardly be doubted that they must occasionally, as suggested by Lyell, have
transported seeds from one part to another of the arctic and antarctic
regions; and during the Glacial period from one part of the now temperate
regions to another. In the Azores, from the large number of plants common
to Europe, in comparison with the species on the other islands of the
Atlantic, which stand nearer to the mainland, and (as remarked by Mr.
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