ars so different an aspect from that in the lower
country... To a geologist, also, there are such manifest proofs of
excessive violence; the strata of the highest pinnacles are tossed about
like the crust of a broken pie." ("L.L." I. pages 259-60.)

Darwin anticipated with intense pleasure his visit to the Galapagos
Islands. On July 12th, 1835, he wrote to Henslow: "In a few days' time
the "Beagle" will sail for the Galapagos Islands. I look forward with
joy and interest to this, both as being somewhat nearer to England and
for the sake of having a good look at an active volcano. Although
we have seen lava in abundance, I have never yet beheld the crater."
("M.L." I. page 26.) He could little anticipate, as he wrote these
lines, the important aid in the solution of the "species question" that
would ever after make his visit to the Galapagos Islands so memorable.
In 1832, as we have seen, the great discovery of the relations of living
to extinct mammals in the same area had dawned upon his mind; in 1835
he was to find a second key for opening up the great mystery, by
recognising the variations of similar types in adjoining islands among
the Galapagos.

The final chapter in the second volume of the "Principles" had aroused
in Darwin's mind a desire to study coral-reefs, which was gratified
during his voyage across the Pacific and Indian Oceans. His theory on
the subject was suggested about the end of 1834 or the beginning of
1835, as he himself tells us, before he had seen a coral-reef,
and resulted from his work during two years in which he had "been
incessantly attending to the effects on the shores of South America of
the intermittent elevation of the land, together with denudation and the
deposition of sediment." ("L.L." I. page 70.)

On arriving at the Cape of Good Hope in July, 1836, Darwin was greatly
gratified by hearing that Sedgwick had spoken to his father in high
terms of praise concerning the work done by him in South America.
Referring to the news from home, when he reached Bahia once more, on the
return voyage (August, 1836), he says: "The desert, volcanic rocks, and
wild sea of Ascension... suddenly wore a pleasing aspect, and I set to
work with a good-will at my old work of Geology." ("L.L." I. page 265.)
Writing fifty years later, he says: "I clambered over the mountains of
Ascension with a bounding step and made the volcanic rocks resound under
my geological hammer!" ("L.L." I. page 66.)

That his d