in a boat,
we were so entangled by these shallows that we could hardly find
our way. Nothing was visible but the flat beds of mud; the day was
not very clear, and there was much refraction, or, as the sailors
expressed it, "things loomed high." The only object within our view
which was not level was the horizon; rushes looked like bushes
unsupported in the air, and water like mudbanks, and mudbanks like
water.

We passed the night in Punta Alta, and I employed myself in
searching for fossil bones; this point being a perfect catacomb for
monsters of extinct races. The evening was perfectly calm and
clear; the extreme monotony of the view gave it an interest even in
the midst of mudbanks and gulls, sand-hillocks and solitary
vultures. In riding back in the morning we came across a very fresh
track of a Puma, but did not succeed in finding it. We saw also a
couple of Zorillos, or skunks,--odious animals, which are far from
uncommon. In general appearance the Zorillo resembles a polecat,
but it is rather larger, and much thicker in proportion. Conscious
of its power, it roams by day about the open plain, and fears
neither dog nor man. If a dog is urged to the attack, its courage
is instantly checked by a few drops of the fetid oil, which brings
on violent sickness and running at the nose. Whatever is once
polluted by it, is for ever useless. Azara says the smell can be
perceived at a league distant; more than once, when entering the
harbour of Monte Video, the wind being off shore, we have perceived
the odour on board the "Beagle." Certain it is, that every animal
most willingly makes room for the Zorillo.

(PLATE 20. BRINGING IN A PRISONER.)

(PLATE 21. IRREGULAR TROOPS.)

CHAPTER V.

Bahia Blanca.
Geology.
Numerous gigantic extinct Quadrupeds.
Recent Extinction.
Longevity of Species.
Large Animals do not require a luxuriant Vegetation.
Southern Africa.
Siberian Fossils.
Two Species of Ostrich.
Habits of Oven-bird.
Armadilloes.
Venomous Snake, Toad, Lizard.
Hybernation of Animals.
Habits of Sea-Pen.
Indian Wars and Massacres.
Arrowhead, antiquarian Relic.

BAHIA BLANCA.

The "Beagle" arrived here on the 24th of August, and a week
afterwards sailed for the Plata. With Captain Fitz Roy's consent I
was left behind, to travel by land to Buenos Ayres. I will here add
some observations, which were made during this visit and on a
previous occasion, when the "Beagle" was employed in surveying the