of sloping deposits, which, before the elevation of the land, had been
accumulated near the then existing shores. It is, however, a
remarkable coincidence, that in the two large islands cut off by the
Beagle Channel from the rest of Tierra del Fuego, one has cliffs
composed of matter that may be called stratified alluvium, which front
similar ones on the opposite side of the channel,--while the other is
exclusively bordered by old crystalline rocks: in the former, called
Navarin Island, both foxes and guanacos occur; but in the latter, Hoste
Island, although similar in every respect, and only separated by a
channel a little more than half a mile wide, I have the word of Jemmy
Button for saying that neither of these animals are found.
The gloomy woods are inhabited by few birds: occasionally the plaintive
note of a white-tufted tyrant-flycatcher (Myiobius albiceps) may be
heard, concealed near the summit of the most lofty trees; and more
rarely the loud strange cry of a black wood-pecker, with a fine scarlet
crest on its head. A little, dusky-coloured wren (Scytalopus
Magellanicus) hops in a skulking manner among the entangled mass of the
fallen and decaying trunks. But the creeper (Oxyurus tupinieri) is the
commonest bird in the country. Throughout the beech forests, high up
and low down, in the most gloomy, wet, and impenetrable ravines, it may
be met with. This little bird no doubt appears more numerous than it
really is, from its habit of following with seeming curiosity any
person who enters these silent woods: continually uttering a harsh
twitter, it flutters from tree to tree, within a few feet of the
intruder's face. It is far from wishing for the modest concealment of
the true creeper (Certhia familiaris); nor does it, like that bird, run
up the trunks of trees, but industriously, after the manner of a
willow-wren, hops about, and searches for insects on every twig and
branch. In the more open parts, three or four species of finches, a
thrush, a starling (or Icterus), two Opetiorhynchi, and several hawks
and owls occur.
The absence of any species whatever in the whole class of Reptiles, is
a marked feature in the zoology of this country, as well as in that of
the Falkland Islands. I do not ground this statement merely on my own
observation, but I heard it from the Spanish inhabitants of the latter
place, and from Jemmy Button with regard to Tierra del Fuego. On the
banks of the Santa Cruz, in 50 degs. south, I saw a frog; and it is
not improbable that these animals, as well as lizards, may be found as
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