om the great difference of climate and vegetation I should not have
expected that many insects would have shown such affinity. It is more
remarkable that the birds on the broad and lofty Cordillera of Tropical
S. America show no affinity with European species. The little power of
diffusion with birds has often struck me as a most singular fact--even
more singular than the great power of diffusion with plants. Remember
that we hope to see you in the autumn.

P.S.--There is a capital paper in the September number of "Annals
and Magazine," translated from Pictet and Humbert, on Fossil Fish of
Lebanon, but you will, I daresay, have received the original. (507/2.
"Recent Researches on the Fossil Fishes of Mount Lebanon," "Ann. Mag.
Nat. Hist." Volume XVIII., page 237, 1866.) It is capital in relation to
modification of species; I would not wish for more confirmatory facts,
though there is no direct allusion to the modification of species.
Hooker, by the way, gave an admirable lecture at Nottingham; I read it
in MS., or rather, heard it. I am glad it will be published, for it was
capital. (507/3. Sir Joseph Hooker delivered a lecture at the Nottingham
meeting of the British Association (1866) on "Insular Floras," published
in the "Gardeners' Chronicle," 1867. See Letters 366-377, etc.)

Sunday morning.

P.S.--I have just received a letter from Asa Gray with the following
passage, so that, according to this, I am the chief cause of Agassiz's
absurd views:--

"Agassiz is back (I have not seen him), and he went at once down to the
National Academy of Sciences, from which I sedulously keep away, and, I
hear, proved to them that the Glacial period covered the whole continent
of America with unbroken ice, and closed with a significant gesture and
the remark: 'So here is the end of the Darwin theory.' How do you like
that?

"I said last winter that Agassiz was bent on covering the whole
continent with ice, and that the motive of the discovery he was sure
to make was to make sure that there should be no coming down of any
terrestrial life from Tertiary or post-Tertiary period to ours. You
cannot deny that he has done his work effectually in a truly imperial
way."

LETTER 508. TO C. LYELL. Down, July 14th, 1868.

Mr. Agassiz's book has been read aloud to me, and I am wonderfully
perplexed what to think about his precise statements of the existence of
glaciers in the Ceara Mountains, and about the drift formation near Rio.
(