ter having been dried, could be
floated across a space of sea 900 miles in width, and would then germinate.
The fact of the larger fruits often floating longer than the small, is
interesting; as plants with large seeds or fruit could hardly be
transported by any other means; and Alph. de Candolle has shown that such
plants generally have restricted ranges.

But seeds may be occasionally transported in another manner. Drift timber
is thrown up on most islands, {361} even on those in the midst of the
widest oceans; and the natives of the coral-islands in the Pacific, procure
stones for their tools, solely from the roots of drifted trees, these
stones being a valuable royal tax. I find on examination, that when
irregularly shaped stones are embedded in the roots of trees, small parcels
of earth are very frequently enclosed in their interstices and behind
them,--so perfectly that not a particle could be washed away in the longest
transport: out of one small portion of earth thus _completely_ enclosed by
wood in an oak about 50 years old, three dicotyledonous plants germinated:
I am certain of the accuracy of this observation. Again, I can show that
the carcasses of birds, when floating on the sea, sometimes escape being
immediately devoured; and seeds of many kinds in the crops of floating
birds long retain their vitality: peas and vetches, for instance, are
killed by even a few days' immersion in sea-water; but some taken out of
the crop of a pigeon, which had floated on artificial salt-water for 30
days, to my surprise nearly all germinated.

Living birds can hardly fail to be highly effective agents in the
transportation of seeds. I could give many facts showing how frequently
birds of many kinds are blown by gales to vast distances across the ocean.
We may I think safely assume that under such circumstances their rate of
flight would often be 35 miles an hour; and some authors have given a far
higher estimate. I have never seen an instance of nutritious seeds passing
through the intestines of a bird; but hard seeds of fruit pass uninjured
through even the digestive organs of a turkey. In the course of two months,
I picked up in my garden 12 kinds of seeds, out of the excrement of small
birds, and these seemed perfect, and some of them, which I tried,
germinated. {362} But the following fact is more important: the crops of
birds do not secrete gastric juice, and do not in the least injure, as I
know by trial, the germina