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Although the beaks and feet of birds are generally
clean,
→OMIT
earth sometimes adheres to them: in one
I removed
→and in another case twenty-two grains of
dry argillaceous earth from
foot of a partridge, and in
earth there was a pebble
as large as the seed of a vetch. Here is a better case: the leg of a woodcock was sent to me by a friend, with a little cake of dry earth attached to the shank, weighing only nine grains; and this contained a seed of the toad-rush (Juncus bufonius) which germinated and flowered. Mr. Swaysland, of Brighton, who during the last forty years has paid close attention to our migratory birds, informs me that he has often shot wagtails (Motacillæ), wheatears, and whin-chats (Saxicolæ), on their first arrival on our shores, before they had alighted; and he has several times noticed little cakes of earth attached to their feet. Many facts could be given showing how
soil is
charged with seeds. ↑
→For instance, Prof.
Newton sent me the leg of a red-legged partridge (Caccabis rufa) which had been wounded and could not
→with
a ball of hard earth
→adhering to it, and weighing
six and a half ounces.
earth had been kept for three years, but when broken, watered and placed under a bell glass, no less than 82 plants sprung
from it: these consisted of
monocotyledons, including the common oat, and at least one kind of grass, and of 70 dicotyledons, which
judging from the young leaves,
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,
can hardly
that they must
→as suggested by Lyell, have
transported seeds from one part to another of the arctic and
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and during the Glacial period from one part of the now temperate regions to another. In the Azores, from the large number of
→OMIT
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. H. C. Watson) from
somewhat northern character
→OMIT
in comparison with the latitude, I suspected that these islands had been partly stocked by ice-borne seeds, during the Glacial epoch. At my request Sir C. Lyell wrote to
Hartung to inquire whether he had observed erratic boulders on these islands, and he answered that he
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