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 will 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. 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 germination 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
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