had here a complete
victory. The few eggs which I have tried both sink and are killed. No
one doubts that salt water would be eminently destructive to them; and I
was really in despair, when I thought I would try them when torpid; and
this day I have taken a lot out of the sea-water, after exactly seven
days' immersion. (337/1. This method of dispersal is not given in the
"Origin"; it seems, therefore, probable that further experiments upset
the conclusion drawn in 1856. This would account for the satisfaction
expressed in the following year at the discovery of another method, on
which Darwin wrote to Sir J.D. Hooker: "The distribution of fresh-water
molluscs has been a horrid incubus to me, but I think I know my way now.
When first hatched they are very active, and I have had thirty or forty
crawl on a dead duck's foot; and they cannot be jerked off, and
will live fifteen or even twenty-four hours out of water" ("Life and
Letters," II., page 93). The published account of these experiments is
in the "Origin," Edition I., page 385.) Some sink and some swim; and in
both cases I have had (as yet) one come to life again, which has quite
astonished and delighted me. I feel as if a thousand-pound weight was
taken off my back. Adios, my dear, kind friend.

I must tell you another of my profound experiments! [Frank] said to me:
"Why should not a bird be killed (by hawk, lightning, apoplexy, hail,
etc.) with seed in its crop, and it would swim?" No sooner said than
done: a pigeon has floated for thirty days in salt water with seeds in
its crop, and they have grown splendidly; and to my great surprise even
tares (Leguminosae, so generally killed by sea-water), which the bird
had naturally eaten, have grown well. You will say gulls and dog-fish,
etc., would eat up the carcase, and so they would 999 times out of
a thousand, but one might escape: I have seen dead land-birds in
sea-drift.

LETTER 338. ASA GRAY TO CHARLES DARWIN.

(338/1. In reply to Darwin's letter given in "Life and Letters," II.,
page 88.)

Cambridge, Mass., February 16th, 1857.

I meant to have replied to your interesting letter of January 1st long
before this time, and also that of November 24th, which I doubt if I
have ever acknowledged. But after getting my school-book, Lessons in
Botany, off my hands--it taking up time far beyond what its size would
seem to warrant--I had to fall hard at work upon a collection of small
size from Japan--mostly N. Japan,