omposed of shells--a white pumiceous stone
like chalk, including gypsum and _infusoria_. At Port St. Julian it is
eight hundred feet thick, and is capped by a mass of gravel forming
probably one of the largest beds of shingle in the world, extending to
the foot of the Cordilleras. For 1,200 miles from the Rio Plata to
Tierra del Fuego the land has been raised by many hundred feet, and the
uprising movement has been interrupted by at least eight long periods of
rest, during which the sea ate deep back into the land, forming at
successive levels the long lines of cliffs, or escarpments, which
separate the different plains as they rise like steps one behind the
other. What a history of geological change does the simply constructed
coast of Patagonia reveal! In some red mud, capping the gravel, I
discovered fossil bones which showed the wonderful relationship in the
same continent between the dead and the living, and will, I have no
doubt, hereafter throw more light on the appearance of organic beings on
our earth and their disappearance from it than any other class of facts.
Patagonia is sterile, but is possessed of a greater stock of rodents
than any other country in the world. The principal animals are the
llamas, in herds up to 500, and the puma, which, with the condor and
other carrion hawks, preys upon them.

From the Strait of Magellan, the Beagle twice made a compass of the
Falkland Islands, and archipelago in nearly the same latitude. It is a
delicate and wretched land, everywhere covered by a peaty soil and wiry
grass of one monotonous colour. The only native quadruped is a large
wolf-like fox, which will soon be as extinct as the dodo. The birds
embrace enormous numbers of sea-fowl, especially geese and penguins. The
wings of a great logger-headed duck called the "steamer" are too weak
for flight; but, by their aid, partly by swimming, partly flapping, they
move very quickly. Thus we found in South America three birds who use
their wings for other purposes besides flight--the penguins as fins, the
"steamers" as paddles, and the ostrich as sails.

Tierra del Fuego may be described as a mountainous land, separated from
the South American continent by the Strait of Magellan, partly submerged
in the sea, so that deep inlets and bays occupy the place where valleys
should exist. The mountain-sides, except on the exposed western coasts,
are covered from the water's edge upwards to the perpetual snow-line by
one great f