tion of seeds; now after a bird has found and
devoured a large supply of food, it is positively asserted that all the
grains do not pass into the gizzard for 12 or even 18 hours. A bird in this
interval might easily be blown to the distance of 500 miles, and hawks are
known to look out for tired birds, and the contents of their torn crops
might thus readily get scattered. Mr. Brent informs me that a friend of his
had to give up flying carrier-pigeons from France to England, as the hawks
on the English coast destroyed so many on their arrival. Some hawks and
owls bolt their prey whole, and after an interval of from twelve to twenty
hours, disgorge pellets, which, as I know from experiments made in the
Zoological Gardens, include seeds capable of germination. Some seeds of the
oat, wheat, millet, canary, hemp, clover, and beet germinated after having
been from twelve to twenty-one hours in the stomachs of different birds of
prey; and two seeds of beet grew after having been thus retained for two
days and fourteen hours. Freshwater fish, I find, eat seeds of many land
and water plants: fish are frequently devoured by birds, and thus the seeds
might be transported from place to place. I forced many kinds of seeds into
the stomachs of dead fish, and then gave their bodies to fishing-eagles,
storks, and pelicans; these birds after an interval of many hours, either
rejected the seeds in pellets or passed them in their excrement; and
several of these seeds retained their power of germination. Certain seeds,
however, were always killed by this process.

Although the beaks and feet of birds are generally quite clean, I can show
that earth sometimes adheres to them: in one instance I removed twenty-two
grains {363} of dry argillaceous earth from one foot of a partridge, and in
this earth there was a pebble quite as large as the seed of a vetch. Thus
seeds might occasionally be transported to great distances; for many facts
could be given showing that soil almost everywhere is charged with seeds.
Reflect for a moment on the millions of quails which annually cross the
Mediterranean; and can we doubt that the earth adhering to their feet would
sometimes include a few minute seeds? But I shall presently 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, I can
hardly doubt that they must occasionally have transported see