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swamps and saline marshes. Changing horses for the last time, we
again began wading through the mud. My animal fell, and I was well
soused in black mire - a very disagreeable accident, when one does
not possess a change of clothes. Some miles from the fort we met a
man, who told us that a great gun had been fired, which is a signal
that Indians are near. We immediately left the road, and followed
the edge of a marsh, which when chased offers the best mode of
escape. We were glad to arrive within the walls, when we found all
the alarm was about nothing, for the Indians turned out to be
friendly ones, who wished to join General Rosas.

Bahia Blanca scarcely deserves the name of a village. A few houses
and the barracks for the troops are enclosed by a deep ditch and
fortified wall. The settlement is only of recent standing (since
1828); and its growth has been one of trouble. The government of
Buenos Ayres unjustly occupied it by force, instead of following
the wise example of the Spanish Viceroys, who purchased the land
near the older settlement of the Rio Negro, from the Indians. Hence
the need of the fortifications; hence the few houses and little
cultivated land without the limits of the walls; even the cattle
are not safe from the attacks of the Indians beyond the boundaries
of the plain on which the fortress stands.

The part of the harbour where the "Beagle" intended to anchor being
distant twenty-five miles, I obtained from the Commandant a guide
and horses, to take me to see whether she had arrived. Leaving the
plain of green turf, which extended along the course of a little
brook, we soon entered on a wide level waste consisting either of
sand, saline marshes, or bare mud. Some parts were clothed by low
thickets, and others with those succulent plants which luxuriate
only where salt abounds. Bad as the country was, ostriches, deers,
agoutis, and armadilloes, were abundant. My guide told me, that two
months before he had a most narrow escape of his life: he was out
hunting with two other men, at no great distance from this part of
the country, when they were suddenly met by a party of Indians, who
giving chase, soon overtook and killed his two friends. His own
horse's legs were also caught by the bolas, but he jumped off, and
with his knife cut them free: while doing this he was obliged to
dodge round his horse, and received two severe wounds from their
chuzos. Springing on the saddle, he managed, by a most wonderful
exertion, just to keep ahead of the long spears of his pursuers,
who followed him to within sight of the fort. From that time there
was an order that no one should stray far from the settlement. I
did not know of this when I started, and was surprised to observe
how earnestly my guide watched a deer, which appeared to have been
frightened from a distant quarter.

We found the "Beagle" had not arrived, and consequently set out on
our return, but the horses soon tiring, we were obliged to bivouac
on the plain. In the morning we had caught an armadillo, which,
although a most excellent dish when roasted in its shell, did not
make a very substantial breakfast and dinner for two hungry men.
The ground at the place where we stopped for the night was
incrusted with a layer of sulphate of soda, and hence, of course,
was without water. Yet many of the smaller rodents managed to exist
even here, and the tucutuco was making its odd little grunt beneath
my head, during half the night. Our horses were very poor ones, and
in the morning they were soon exhausted from not having had
anything to drink, so that we were obliged to walk. About noon the
dogs killed a kid, which we roasted. I ate some of it, but it made
me intolerably thirsty. This was the more distressing as the road,
from some recent rain, was full of little puddles of clear water,
yet not a drop was drinkable. I had scarcely been twenty hours
without water, and only part of the time under a hot sun, yet the
thirst rendered me very weak. How people survive two or three days
under such circumstances, I cannot imagine: at the same time, I
must confess that my guide did not suffer at all, and was
astonished that one day's deprivation should be so troublesome to
me.

I have several times alluded to the surface of the ground being
incrusted with salt. This phenomenon is quite different from that
of the salinas, and more extraordinary. In many parts of South
America, wherever the climate is moderately dry, these
incrustations occur; but I have nowhere seen them so abundant as
near Bahia Blanca. The salt here, and in other parts of Patagonia,
consists chiefly of sulphate of soda with some common salt. As long
as the ground remains moist in the salitrales (as the Spaniards
improperly call them, mistaking this substance for saltpetre),
nothing is to be seen but an extensive plain composed of a black,
muddy soil, supporting scattered tufts of succulent plants. On
returning through one of these tracts, after a week's hot weather,
one is surprised to see square miles of the plain white, as if from
a slight fall of snow, here and there heaped up by the wind into
little drifts. This latter appearance is chiefly caused by the
salts being drawn up, during the slow evaporation of the moisture,
round blades of dead grass, stumps of wood, and pieces of broken
earth, instead of being crystallised at the bottoms of the puddles
of water.

The salitrales occur either on level tracts elevated only a few
feet above the level of the sea, or on alluvial land bordering
rivers. M. Parchappe found that the saline incrustation on the
plain, at the distance of some miles from the sea, consisted
chiefly of sulphate of soda, with only seven per cent of common
salt; whilst nearer to the coast, the common salt increased to 37
parts in a hundred. (4/7. "Voyage dans l'Amerique Merid." par M. A.
d'Orbigny. Part. Hist. tome 1 page 664.) This circumstance would
tempt one to believe that the sulphate of soda is generated in the
soil, from the muriate left on the surface during the slow and
recent elevation of this dry country. The whole phenomenon is well
worthy the attention of naturalists. Have the succulent,
salt-loving plants, which are well known to contain much soda, the
power of decomposing the muriate? Does the black fetid mud,
abounding with organic matter, yield the sulphur and ultimately the
sulphuric acid?

Two days afterwards I again rode to the harbour: when not far from
our destination, my companion, the same man as before, spied three
people hunting on horseback. He immediately dismounted, and
watching them intently, said, "They don't ride like Christians, and
nobody can leave the fort." The three hunters joined company, and
likewise dismounted from their horses. At last one mounted again
and rode over the hill out of sight. My companion said, "We must
now get on our horses: load your pistol;" and he looked to his own
sword. I asked, "Are they Indians?" - "Quien sabe? (who knows?) if
there are no more than three, it does not signify." It then struck
me, that the one man had gone over the hill to fetch the rest of
his tribe. I suggested this; but all the answer I could extort was,
"Quien sabe?" His head and eye never for a minute ceased scanning
slowly the distant horizon. I thought his uncommon coolness too
good a joke, and asked him why he did not return home. I was
startled when he answered, "We are returning, but in a line so as
to pass near a swamp, into which we can gallop the horses as far as
they can go, and then trust to our own legs; so that there is no
danger." I did not feel quite so confident of this, and wanted to
increase our pace. He said, "No, not until they do." When any
little inequality concealed us, we galloped; but when in sight,
continued walking. At last we reached a valley, and turning to the
left, galloped quickly to the foot of a hill; he gave me his horse
to hold, made the dogs lie down, and then crawled on his hands and
knees to reconnoitre. He remained in this position for some time,
and at last, bursting out in laughter, exclaimed, "Mugeres!"
(women!) He knew them to be the wife and sister-in-law of the
major's son, hunting for ostrich's eggs.

I have described this man's conduct, because he acted under the
full impression that they were Indians. As soon, however, as the
absurd mistake was found out, he gave me a hundred reasons why they
could not have been Indians; but all these were forgotten at the
time. We then rode on in peace and quietness to a low point called
Punta Alta, whence we could see nearly the whole of the great
harbour of Bahia Blanca.

The wide expanse of water is choked up by numerous great mudbanks,
which the inhabitants call Cangrejales, or crabberies, from the
number of small crabs. The mud is so soft that it is impossible to
walk over them, even for the shortest distance. Many of the banks
have their surfaces covered with long rushes, the tops of which
alone are visible at high water. On one occasion, when 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
harbour.

The plain, at the distance of a few miles from the coast, belongs
to the great Pampean formation, which consists in part of a reddish
clay, and in part of a highly calcareous marly rock. Nearer the
coast there are some plains formed from the wreck of the upper
plain, and from mud, gravel, and sand thrown up by the sea during
the slow elevation of the land, of which elevation we have evidence
in upraised beds of recent shells, and in rounded pebbles of pumice
scattered over the country. At Punta Alta we have a section of one
of these later-formed little plains, which is highly interesting
from the number and extraordinary character of the remains of
gigantic land-animals embedded in it. These have been fully
described by Professor Owen, in the "Zoology of the Voyage of the
'Beagle,'" and are deposited in the College of Surgeons. I will
here give only a brief outline of their nature.

First, parts of three heads and other bones of the Megatherium, the
huge dimensions of which are expressed by its name. Secondly, the
Megalonyx, a great allied animal. Thirdly, the Scelidotherium, also
an allied animal, of which I obtained a nearly perfect skeleton. It
must have been as large as a rhinoceros: in the structure of its
head it comes, according to Mr. Owen, nearest to the Cape
Ant-eater, but in some other respects it approaches to the
armadilloes. Fourthly, the Mylodon Darwinii, a closely related
genus of little inferior size. Fifthly, another gigantic edental
quadruped. Sixthly, a large animal, with an osseous coat in
compartments, very like that of an armadillo. Seventhly, an extinct
kind of horse, to which I shall have again to refer. Eighthly, a
tooth of a Pachydermatous animal, probably the same with the
Macrauchenia, a huge beast with a long neck like a camel, which I
shall also refer to again. Lastly, the Toxodon, perhaps one of the
strangest animals ever discovered: in size it equalled an elephant
or megatherium, but the structure of its teeth, as Mr. Owen states,
proves indisputably that it was intimately related to the Gnawers,
the order which, at the present day, includes most of the smallest
quadrupeds: in many details it is allied to the Pachydermata:
judging from the position of its eyes, ears, and nostrils, it was
probably aquatic, like the Dugong and Manatee, to which it is also
allied. How wonderfully are the different Orders, at the present
time so well separated, blended together in different points of the
structure of the Toxodon!

The remains of these nine great quadrupeds and many detached bones
were found embedded on the beach, within the space of about 200
yards square. It is a remarkable circumstance that so many
different species should be found together; and it proves how
numerous in kind the ancient inhabitants of this country must have
been. At the distance of about thirty miles from Punta Alta, in a
cliff of red earth, I found several fragments of bones, some of
large size. Among them were the teeth of a gnawer, equalling in
size and closely resembling those of the Capybara, whose habits
have been described; and therefore, probably, an aquatic animal.
There was also part of the head of a Ctenomys; the species being
different from the Tucutuco, but with a close general resemblance.
The red earth, like that of the Pampas, in which these remains were
embedded, contains, according to Professor Ehrenberg, eight
fresh-water and one salt-water infusorial animalcule; therefore,
probably, it was an estuary deposit.

The remains at Punta Alta were embedded in stratified gravel and
reddish mud, just such as the sea might now wash up on a shallow
bank. They were associated with twenty-three species of shells, of
which thirteen are recent and four others very closely related to
recent forms. (5/1. Since this was written, M. Alcide d'Orbigny has
examined these shells, and pronounces them all to be recent.) From
the bones of the Scelidotherium, including even the kneecap, being
entombed in their proper relative positions, and from the osseous
armour of the great armadillo-like animal being so well preserved,
together with the bones of one of its legs, we may feel assured
that these remains were fresh and united by their ligaments, when
deposited in the gravel together with the shells. (5/2. M. Aug.
Bravard has described, in a Spanish work "Observaciones Geologicas"
1857, this district, and he believes that the bones of the extinct
mammals were washed out of the underlying Pampean deposit, and
subsequently became embedded with the still existing shells; but I
am not convinced by his remarks. M. Bravard believes that the whole
enormous Pampean deposit is a sub-aerial formation, like
sand-dunes: this seems to me to be an untenable doctrine.) Hence we
have good evidence that the above enumerated gigantic quadrupeds,
more different from those of the present day than the oldest of the
tertiary quadrupeds of Europe, lived whilst the sea was peopled
with most of its present inhabitants; and we have confirmed that
remarkable law so often insisted on by Mr. Lyell, namely, that the
"longevity of the species in the mammalia is upon the whole
inferior to that of the testacea." (5/3. "Principles of Geology"
volume 4 page 40.)

The great size of the bones of the Megatheroid animals, including
the Megatherium, Megalonyx, Scelidotherium, and Mylodon, is truly
wonderful. The habits of life of these animals were a complete
puzzle to naturalists, until Professor Owen solved the problem with
remarkable ingenuity. (5/4. This theory was first developed in the
"Zoology of the Voyage of the 'Beagle,'" and subsequently in
Professor Owen's "Memoir on Mylodon robustus.") The teeth indicate,
by their simple structure, that these Megatheroid animals lived on
vegetable food, and probably on the leaves and small twigs of
trees; their ponderous forms and great strong curved claws seem so
little adapted for locomotion, that some eminent naturalists have
actually believed that, like the sloths, to which they are
intimately related, they subsisted by climbing back downwards on
trees, and feeding on the leaves. It was a bold, not to say
preposterous, idea to conceive even antediluvian trees, with
branches strong enough to bear animals as large as elephants.
Professor Owen, with far more probability, believes that, instead
of climbing on the trees, they pulled the branches down to them,
and tore up the smaller ones by the roots, and so fed on the
leaves. The colossal breadth and weight of their hinder quarters,
which can hardly be imagined without having been seen, become, on
this view, of obvious service, instead of being an encumbrance:
their apparent clumsiness disappears. With their great tails and
their huge heels firmly fixed like a tripod on the ground, they
could freely exert the full force of their most powerful arms and
great claws. Strongly rooted, indeed, must that tree have been,
which could have resisted such force! The Mylodon, moreover, was
furnished with a long extensile tongue like that of the giraffe,
which, by one of those beautiful provisions of nature, thus reaches
with the aid of its long neck its leafy food. I may remark, that in
Abyssinia the elephant, according to Bruce, when it cannot reach
with its proboscis the branches, deeply scores with its tusks the
trunk of the tree, up and down and all round, till it is
sufficiently weakened to be broken down.

The beds including the above fossil remains stand only from fifteen
to twenty feet above the level of high water; and hence the
elevation of the land has been small (without there has been an
intercalated period of subsidence, of which we have no evidence)
since the great quadrupeds wandered over the surrounding plains;
and the external features of the country must then have been very
nearly the same as now. What, it may naturally be asked, was the
character of the vegetation at that period; was the country as
wretchedly sterile as it now is? As so many of the co-embedded
shells are the same with those now living in the bay, I was at
first inclined to think that the former vegetation was probably
similar to the existing one; but this would have been an erroneous
inference, for some of these same shells live on the luxuriant
coast of Brazil; and generally, the characters of the inhabitants
of the sea are useless as guides to judge of those on the land.
Nevertheless, from the following considerations, I do not believe
that the simple fact of many gigantic quadrupeds having lived on
the plains round Bahia Blanca, is any sure guide that they formerly
were clothed with a luxuriant vegetation: I have no doubt that the
sterile country a little southward, near the Rio Negro, with its
scattered thorny trees, would support many and large quadrupeds.

That large animals require a luxuriant vegetation, has been a
general assumption which has passed from one work to another; but I
do not hesitate to say that it is completely false, and that it has
vitiated the reasoning of geologists on some points of great
interest in the ancient history of the world. The prejudice has
probably been derived from India, and the Indian islands, where
troops of elephants, noble forests, and impenetrable jungles, are
associated together in every one's mind. If, however, we refer to
any work of travels through the southern parts of Africa, we shall
find allusions in almost every page either to the desert character
of the country, or to the numbers of large animals inhabiting it.
The same thing is rendered evident by the many engravings which
have been published of various parts of the interior. When the
"Beagle" was at Cape Town, I made an excursion of some days' length
into the country, which at least was sufficient to render that
which I had read more fully intelligible.

Dr. Andrew Smith, who, at the head of his adventurous party, has
lately succeeded in passing the Tropic of Capricorn, informs me
that, taking into consideration the whole of the southern part of
Africa, there can be no doubt of its being a sterile country. On
the southern and south-eastern coasts there are some fine forests,
but with these exceptions, the traveller may pass for days together
through open plains, covered by a poor and scanty vegetation. It is
difficult to convey any accurate idea of degrees of comparative
fertility; but it may be safely said that the amount of vegetation
supported at any one time by Great Britain, exceeds, perhaps even
tenfold, the quantity on an equal area in the interior parts of
Southern Africa. (5/5. I mean by this to exclude the total amount
which may have been successively produced and consumed during a
given period.) The fact that bullock-waggons can travel in any
direction, excepting near the coast, without more than occasionally
half an hour's delay in cutting down bushes, gives, perhaps, a more
definite notion of the scantiness of the vegetation. Now, if we
look to the animals inhabiting these wide plains, we shall find
their numbers extraordinarily great, and their bulk immense. We
must enumerate the elephant, three species of rhinoceros, and
probably, according to Dr. Smith, two others, the hippopotamus, the
giraffe, the bos caffer - as large as a full-grown bull, and the
elan - but little less, two zebras, and the quaccha, two gnus, and
several antelopes even larger than these latter animals. It may be
supposed that although the species are numerous, the individuals of
each kind are few. By the kindness of Dr. Smith, I am enabled to
show that the case is very different. He informs me, that in
latitude 24 degrees, in one day's march with the bullock-waggons,
he saw, without wandering to any great distance on either side,
between one hundred and one hundred and fifty rhinoceroses, which
belonged to three species: the same day he saw several herds of
giraffes, amounting together to nearly a hundred; and that,
although no elephant was observed, yet they are found in this
district. At the distance of a little more than one hour's march
from their place of encampment on the previous night, his party
actually killed at one spot eight hippopotamuses, and saw many
more. In this same river there were likewise crocodiles. Of course
it was a case quite extraordinary, to see so many great animals
crowded together, but it evidently proves that they must exist in
great numbers. Dr. Smith describes the country passed through that
day, as "being thinly covered with grass, and bushes about four
feet high, and still more thinly with mimosa-trees." The waggons
were not prevented travelling in a nearly straight line.

Besides these large animals, every one the least acquainted with
the natural history of the Cape has read of the herds of antelopes,
which can be compared only with the flocks of migratory birds. The
numbers indeed of the lion, panther, and hyaena, and the multitude
of birds of prey, plainly speak of the abundance of the smaller
quadrupeds: one evening seven lions were counted at the same time
prowling round Dr. Smith's encampment. As this able naturalist
remarked to me, the carnage each day in Southern Africa must indeed
be terrific! I confess it is truly surprising how such a number of



Online LibraryCharles DarwinThe Voyage of the Beagle → online text (page 9 of 51)