In the morning (17th) we landed on Chatham Island, which, like the others, rises with a tame and rounded outline, broken here and there by scattered hillocks, the remains of former craters.
The Beagle sailed round Chatham Island, and anchored in several bays.
In the first part of the road we passed through leafless thickets, as in Chatham Island. Higher up, the woods gradually became greener; and as soon as we crossed the ridge of the island, we were cooled by a fine southerly breeze, and our sight refreshed by a green and thriving vegetation.
Of terrestrial mammals, there is only one which must be considered as indigenous, namely, a mouse (Mus Galapagoensis), and this is confined, as far as I could ascertain, to Chatham Island, the most easterly island of the group.
When I landed at Chatham Island, I could not imagine what animal travelled so methodically along well-chosen tracks.
Now let us suppose the mocking-thrush of Chatham Island
to be blown to Charles Island, which has its own mocking-thrush: why should it succeed in establishing itself there?