The Voyage Of The Beagle

Chapter II

 

(PLATE 8. BOTOFOGO BAY, RIO DE JANEIRO.)

Rio de Janeiro.
Excursion north of Cape Frio.
Great Evaporation.
Slavery.
Botofogo Bay.
Terrestrial Planariae.
Clouds on the Corcovado.
Heavy Rain.
Musical Frogs.
Phosphorescent Insects.
Elater, springing powers of.
Blue Haze.
Noise made by a Butterfly.
Entomology.
Ants.
Wasp killing a Spider.
Parasitical Spider.
Artifices of an Epeira.
Gregarious Spider.
Spider with an unsymmetrical Web.

RIO DE JANEIRO.

APRIL 4 TO JULY 5, 1832.

A few days after our arrival I became acquainted with an Englishman
who was going to visit his estate, situated rather more than a
hundred miles from the capital, to the northward of Cape Frio. I
gladly accepted his kind offer of allowing me to accompany him.

APRIL 8, 1832.

Our party amounted to seven. The first stage was very interesting.
The day was powerfully hot, and as we passed through the woods,
everything was motionless, excepting the large and brilliant
butterflies, which lazily fluttered about. The view seen when
crossing the hills behind Praia Grande was most beautiful; the
colours were intense, and the prevailing tint a dark blue; the sky
and the calm waters of the bay vied with each other in splendour.
After passing through some cultivated country, we entered a forest
which in the grandeur of all its parts could not be exceeded. We
arrived by midday at Ithacaia; this small village is situated on a
plain, and round the central house are the huts of the negroes.
These, from their regular form and position, reminded me of the
drawings of the Hottentot habitations in Southern Africa. As the
moon rose early, we determined to start the same evening for our
sleeping-place at the Lagoa Marica. As it was growing dark we
passed under one of the massive, bare, and steep hills of granite
which are so common in this country. This spot is notorious from
having been, for a long time, the residence of some runaway slaves,
who, by cultivating a little ground near the top, contrived to eke
out a subsistence. At length they were discovered, and a party of
soldiers being sent, the whole were seized with the exception of
one old woman, who, sooner than again be led into slavery, dashed
herself to pieces from the summit of the mountain. In a Roman
matron this would have been called the noble love of freedom: in a
poor negress it is mere brutal obstinacy. We continued riding for
some hours. For the few last miles the road was intricate, and it
passed through a desert waste of marshes and lagoons. The scene by
the dimmed light of the moon was most desolate. A few fireflies
flitted by us; and the solitary snipe, as it rose, uttered its
plaintive cry. The distant and sullen roar of the sea scarcely
broke the stillness of the night.

APRIL 9, 1832.

We left our miserable sleeping-place before sunrise. The road
passed through a narrow sandy plain, lying between the sea and the
interior salt lagoons. The number of beautiful fishing birds, such
as egrets and cranes, and the succulent plants assuming most
fantastical forms, gave to the scene an interest which it would not
otherwise have possessed. The few stunted trees were loaded with
parasitical plants, among which the beauty and delicious fragrance
of some of the orchideae were most to be admired.

The great site of climbing parasitic plants reminds us of the parasitic nutrition where the parasite gets it readymade food from the host plant. This is established by maintaining a lower water potential than the host. These plants do not contain chlorophyll, the necessary elements required for photosynthesis. Some examples of this include the

  • Cuscuta
  • Santalaceae

As the sun rose,
the day became extremely hot, and the reflection of the light and
heat from the white sand was very distressing. We dined at
Mandetiba; the thermometer in the shade being 84 degrees. The
beautiful view of the distant wooded hills, reflected in the
perfectly calm water of an extensive lagoon, quite refreshed us. As
the vênda here was a very good one, and I have the pleasant, but
rare remembrance, of an excellent dinner, I will be grateful and
presently describe it, as the type of its class. (2/1. Vênda, the
Portuguese name for an inn.) These houses are often large, and are
built of thick upright posts, with boughs interwoven, and
afterwards plastered. They seldom have floors, and never glazed
windows; but are generally pretty well roofed. Universally the
front part is open, forming a kind of verandah, in which tables and
benches are placed. The bedrooms join on each side, and here the
passenger may sleep as comfortably as he can, on a wooden platform
covered by a thin straw mat. The vênda stands in a courtyard, where
the horses are fed. On first arriving, it was our custom to
unsaddle the horses and give them their Indian corn; then, with a
low bow, to ask the senhôr to do us the favour to give us something
to eat. “Anything you choose, sir,” was his usual answer. For the
few first times, vainly I thanked providence for having guided us
to so good a man. The conversation proceeding, the case universally
became deplorable. “Any fish can you do us the favour of giving
?”–“Oh no, sir.”–“Any soup?”–“No, sir.”–“Any bread?”–“Oh no,
sir.”–“Any dried meat?”–“Oh no, sir.” If we were lucky, by
waiting a couple of hours, we obtained fowls, rice, and farinha. It
not unfrequently happened that we were obliged to kill, with
stones, the poultry for our own supper. When, thoroughly exhausted
by fatigue and hunger, we timorously hinted that we should be glad
of our meal, the pompous, and (though true) most unsatisfactory
answer was, “It will be ready when it is ready.” If we had dared to
remonstrate any further, we should have been told to proceed on our
journey, as being too impertinent. The hosts are most ungracious
and disagreeable in their manners; their houses and their persons
are often filthily dirty; the want of the accommodation of forks,
knives, and spoons is common; and I am sure no cottage or hovel in
England could be found in a state so utterly destitute of every
comfort. At Campos Novos, however, we fared sumptuously; having
rice and fowls, biscuit, wine, and spirits, for dinner; coffee in
the evening, and fish with coffee for breakfast. All this, with
good food for the horses, only cost 2 shillings 6 pence per head.
Yet the host of this vênda, being asked if he knew anything of a
whip which one of the party had lost, gruffly answered, “How should
I know? why did you not take care of it?–I suppose the dogs have
eaten it.”

Leaving Mandetiba, we continued to pass through an intricate
wilderness of lakes; in some of which were fresh, in others salt
water shells. Of the former kind, I found a Limnaea in great
numbers in a lake, into which the inhabitants assured me that the
sea enters once a year, and sometimes oftener, and makes the water
quite salt. I have no doubt many interesting facts in relation to
marine and fresh-water animals might be observed in this chain of
lagoons which skirt the coast of Brazil. M. Gay has stated that he
found in the neighbourhood of Rio shells of the marine genera solen
and mytilus, and fresh-water ampullariae, living together in
brackish water. (2/2. “Annales des Sciences Naturelles” for 1833.)
I also frequently observed in the lagoon near the Botanic Garden,
where the water is only a little less salt than in the sea, a
species of hydrophilus, very similar to a water-beetle common in
the ditches of England: in the same lake the only shell belonged to
a genus generally found in estuaries.

(PLATE 9. VAMPIRE BAT (Desmodus D’Orbigny). Caught on back of
Darwin’s horse near Coquimbo. Head, full size.)

Leaving the coast for a time, we again entered the forest. The
trees were very lofty, and remarkable, compared with those of
Europe, from the whiteness of their trunks. I see by my notebook,
“wonderful and beautiful flowering parasites,” invariably struck me
as the most novel object in these grand scenes. Travelling onwards
we passed through tracts of pasturage, much injured by the enormous
conical ants’ nests, which were nearly twelve feet high. They gave
to the plain exactly the appearance of the mud volcanoes at
Jorullo, as figured by Humboldt. We arrived at Engenhodo after it
was dark, having been ten hours on horseback. I never ceased,
during the whole journey, to be surprised at the amount of labour
which the horses were capable of enduring; they appeared also to
recover from any injury much sooner than those of our English
breed. The Vampire bat is often the cause of much trouble, by
biting the horses on their withers. The injury is generally not so
much owing to the loss of blood, as to the inflammation which the
pressure of the saddle afterwards produces. The whole circumstance
has lately been doubted in England; I was therefore fortunate in
being present when one (Desmodus d’orbignyi, Wat.) was actually
caught on a horse’s back. We were bivouacking late one evening near
Coquimbo, in Chile, when my servant, noticing that one of the
horses was very restive, went to see what was the matter, and
fancying he could distinguish something, suddenly put his hand on
the beast’s withers, and secured the vampire. In the morning the
spot where the bite had been inflicted was easily distinguished
from being slightly swollen and bloody. The third day afterwards we
rode the horse, without any ill effects.

APRIL 13, 1832.

After three days’ travelling we arrived at Socêgo, the estate of
Senhôr Manuel Figuireda, a relation of one of our party. The house
was simple, and, though like a barn in form, was well suited to the
climate. In the sitting-room gilded chairs and sofas were oddly
contrasted with the whitewashed walls, thatched roof, and windows
without glass. The house, together with the granaries, the stables,
and workshops for the blacks, who had been taught various trades,
formed a rude kind of quadrangle; in the centre of which a large
pile of coffee was drying. These buildings stand on a little hill,
overlooking the cultivated ground, and surrounded on every side by
a wall of dark green luxuriant forest. The chief produce of this
part of the country is coffee. Each tree is supposed to yield
annually, on an average, two pounds; but some give as much as
eight. Mandioca or cassava is likewise cultivated in great
quantity. Every part of this plant is useful: the leaves and stalks
are eaten by the horses, and the roots are ground into a pulp,
which, when pressed dry and baked, forms the farinha, the principal
article of sustenance in the Brazils. It is a curious, though
well-known fact, that the juice of this most nutritious plant is
highly poisonous. A few years ago a cow died at this Fazênda, in
consequence of having drunk some of it. Senhôr Figuireda told me
that he had planted, the year before, one bag of feijaô or beans,
and three of rice; the former of which produced eighty, and the
latter three hundred and twenty fold. The pasturage supports a fine
stock of cattle, and the woods are so full of game that a deer had
been killed on each of the three previous days. This profusion of
food showed itself at dinner, where, if the tables did not groan,
the guests surely did; for each person is expected to eat of every
dish. One day, having, as I thought, nicely calculated so that
nothing should go away untasted, to my utter dismay a roast turkey
and a pig appeared in all their substantial reality. During the
meals, it was the employment of a man to drive out of the room
sundry old hounds, and dozens of little black children, which
crawled in together, at every opportunity. As long as the idea of
slavery could be banished, there was something exceedingly
fascinating in this simple and patriarchal style of living: it was
such a perfect retirement and independence from the rest of the
world. As soon as any stranger is seen arriving, a large bell is
set tolling, and generally some small cannon are fired. The event
is thus announced to the rocks and woods, but to nothing else. One
morning I walked out an hour before daylight to admire the solemn
stillness of the scene; at last, the silence was broken by the
morning hymn, raised on high by the whole body of the blacks; and
in this manner their daily work is generally begun. On such
fazêndas as these, I have no doubt the slaves pass happy and
contented lives. On Saturday and Sunday they work for themselves,
and in this fertile climate the labour of two days is sufficient to
support a man and his family for the whole week.

APRIL 14, 1832.

(PLATE 10. VIRGIN FOREST.)

Leaving Socˆgo, we rode to another estate on the Rio Macƒe, which
was the last patch of cultivated ground in that direction. The
estate was two and a half miles long, and the owner had forgotten
how many broad. Only a very small piece had been cleared, yet
almost every acre was capable of yielding all the various rich
productions of a tropical land. Considering the enormous area of
Brazil, the proportion of cultivated ground can scarcely be
considered as anything compared to that which is left in the state
of nature: at some future age, how vast a population it will
support! During the second day’s journey we found the road so shut
up that it was necessary that a man should go ahead with a sword to
cut away the creepers. The forest abounded with beautiful objects;
among which the tree ferns, though not large, were, from their
bright green foliage, and the elegant curvature of their fronds,
most worthy of admiration. In the evening it rained very heavily,
and although the thermometer stood at 65 degrees, I felt very cold.
As soon as the rain ceased, it was curious to observe the
extraordinary evaporation which commenced over the whole extent of
the forest. At the height of a hundred feet the hills were buried
in a dense white vapour, which rose like columns of smoke from the
most thickly-wooded parts, and especially from the valleys. I
observed this phenomenon on several occasions: I suppose it is
owing to the large surface of foliage, previously heated by the
sun’s rays.

While staying at this estate, I was very nearly being an
eye-witness to one of those atrocious acts which can only take
place in a slave country. Owing to a quarrel and a lawsuit, the
owner was on the point of taking all the women and children from
the male slaves, and selling them separately at the public auction
at Rio. Interest, and not any feeling of compassion, prevented this
act. Indeed, I do not believe the inhumanity of separating thirty
families, who had lived together for many years, even occurred to
the owner. Yet I will pledge myself, that in humanity and good
feeling he was superior to the common run of men. It may be said
there exists no limit to the blindness of interest and selfish
habit. I may mention one very trifling anecdote, which at the time
struck me more forcibly than any story of cruelty. I was crossing a
ferry with a negro who was uncommonly stupid. In endeavouring to
make him understand, I talked loud, and made signs, in doing which
I passed my hand near his face. He, I suppose, thought I was in a
passion, and was going to strike him; for instantly, with a
frightened look and half-shut eyes, he dropped his hands. I shall
never forget my feelings of surprise, disgust, and shame, at seeing
a great powerful man afraid even to ward off a blow, directed, as
he thought, at his face. This man had been trained to a degradation
lower than the slavery of the most helpless animal.

APRIL 18, 1832.

(PLATE 11. CABBAGE PALM.)

In returning we spent two days at Socˆgo, and I employed them in
collecting insects in the forest. The greater number of trees,
although so lofty, are not more than three or four feet in
circumference. There are, of course, a few of much greater
dimension. Senhôr Manuel was then making a canoe 70 feet in length
from a solid trunk, which had originally been 110 feet long, and of
great thickness. The contrast of palm trees, growing amidst the
common branching kinds, never fails to give the scene an
intertropical character. Here the woods were ornamented by the
Cabbage Palm–one of the most beautiful of its family. With a stem
so narrow that it might be clasped with the two hands, it waves its
elegant head at the height of forty or fifty feet above the ground.
The woody creepers, themselves covered by other creepers, were of
great thickness: some which I measured were two feet in
circumference. Many of the older trees presented a very curious
appearance from the tresses of a liana hanging from their boughs,
and resembling bundles of hay. If the eye was turned from the world
of foliage above, to the ground beneath, it was attracted by the
extreme elegance of the leaves of the ferns and mimosae. The
latter, in some parts, covered the surface with a brushwood only a
few inches high. In walking across these thick beds of mimosae, a
broad track was marked by the change of shade, produced by the
drooping of their sensitive petioles. It is easy to specify the
individual objects of admiration in these grand scenes; but it is
not possible to give an adequate idea of the higher feelings of
wonder, astonishment, and devotion, which fill and elevate the
mind.

(PLATE 12. MANDIOCA OR CASSAVA.)

APRIL 19, 1832.

Leaving Socˆgo, during the two first days we retraced our steps. It
was very wearisome work, as the road generally ran across a glaring
hot sandy plain, not far from the coast. I noticed that each time
the horse put its foot on the fine siliceous sand, a gentle
chirping noise was produced. On the third day we took a different
line, and passed through the gay little village of Madre de De“s.
This is one of the principal lines of road in Brazil; yet it was in
so bad a state that no wheel vehicle, excepting the clumsy
bullock-wagon, could pass along. In our whole journey we did not
cross a single bridge built of stone; and those made of logs of
wood were frequently so much out of repair that it was necessary to
go on one side to avoid them. All distances are inaccurately known.
The road is often marked by crosses, in the place of milestones, to
signify where human blood has been spilled. On the evening of the
23rd we arrived at Rio, having finished our pleasant little
excursion.

During the remainder of my stay at Rio, I resided in a cottage at
Botofogo Bay. It was impossible to wish for anything more
delightful than thus to spend some weeks in so magnificent a
country. In England any person fond of natural history enjoys in
his walks a great advantage, by always having something to attract
his attention; but in these fertile climates, teeming with life,
the attractions are so numerous, that he is scarcely able to walk
at all.

The few observations which I was enabled to make were almost
exclusively confined to the invertebrate animals. The existence of
a division of the genus Planaria, which inhabits the dry land,
interested me much. These animals are of so simple a structure,
that Cuvier has arranged them with the intestinal worms, though
never found within the bodies of other animals. Numerous species
inhabit both salt and fresh water; but those to which I allude were
found, even in the drier parts of the forest, beneath logs of
rotten wood, on which I believe they feed. In general form they
resemble little slugs, but are very much narrower in proportion,
and several of the species are beautifully coloured with
longitudinal stripes. Their structure is very simple: near the
middle of the under or crawling surface there are two small
transverse slits, from the anterior one of which a funnel-shaped
and highly irritable mouth can be protruded. For some time after
the rest of the animal was completely dead from the effects of salt
water or any other cause, this organ still retained its vitality.

I found no less than twelve different species of terrestrial
Planariae in different parts of the southern hemisphere. (2/3. I
have described and named these species in the “Annals of Natural
History” volume 14 page 241.) Some specimens which I obtained at
Van Dieman’s Land, I kept alive for nearly two months, feeding them
on rotten wood. Having cut one of them transversely into two nearly
equal parts, in the course of a fortnight both had the shape of
perfect animals. I had, however, so divided the body, that one of
the halves contained both the inferior orifices, and the other, in
consequence, none. In the course of twenty-five days from the
operation, the more perfect half could not have been distinguished
from any other specimen. The other had increased much in size; and
towards its posterior end, a clear space was formed in the
parenchymatous mass, in which a rudimentary cup-shaped mouth could
clearly be distinguished; on the under surface, however, no
corresponding slit was yet open. If the increased heat of the
weather, as we approached the equator, had not destroyed all the
individuals, there can be no doubt that this last step would have
completed its structure. Although so well known an experiment, it
was interesting to watch the gradual production of every essential
organ, out of the simple extremity of another animal. It is
extremely difficult to preserve these Planariae; as soon as the
cessation of life allows the ordinary laws of change to act, their
entire bodies become soft and fluid, with a rapidity which I have
never seen equalled.

I first visited the forest in which these Planariae were found, in
company with an old Portuguese priest who took me out to hunt with
him. The sport consisted in turning into the cover a few dogs, and
then patiently waiting to fire at any animal which might appear. We
were accompanied by the son of a neighbouring farmer–a good
specimen of a wild Brazilian youth. He was dressed in a tattered
old shirt and trousers, and had his head uncovered: he carried an
old-fashioned gun and a large knife. The habit of carrying the
knife is universal; and in traversing a thick wood it is almost
necessary, on account of the creeping plants. The frequent
occurrence of murder may be partly attributed to this habit. The
Brazilians are so dexterous with the knife that they can throw it
to some distance with precision, and with sufficient force to cause
a fatal wound. I have seen a number of little boys practising this
art as a game of play, and from their skill in hitting an upright
stick, they promised well for more earnest attempts. My companion,
the day before, had shot two large bearded monkeys. These animals
have prehensile tails, the extremity of which, even after death,
can support the whole weight of the body. One of them thus remained
fast to a branch, and it was necessary to cut down a large tree to
procure it. This was soon effected, and down came tree and monkey
with an awful crash. Our day’s sport, besides the monkey, was
confined to sundry small green parrots and a few toucans. I
profited, however, by my acquaintance with the Portuguese padre,
for on another occasion he gave me a fine specimen of the
Yagouaroundi cat.

Every one has heard of the beauty of the scenery near Botofogo. The
house in which I lived was seated close beneath the well-known
mountain of the Corcovado. It has been remarked, with much truth,
that abruptly conical hills are characteristic of the formation
which Humboldt designates as gneiss-granite. Nothing can be more
striking than the effect of these huge rounded masses of naked rock
rising out of the most luxuriant vegetation.

I was often interested by watching the clouds, which, rolling in
from seaward, formed a bank just beneath the highest point of the
Corcovado. This mountain, like most others, when thus partly
veiled, appeared to rise to a far prouder elevation than its real
height of 2300 feet. Mr. Daniell has observed, in his
meteorological essays, that a cloud sometimes appears fixed on a
mountain summit, while the wind continues to blow over it. The same
phenomenon here presented a slightly different appearance. In this
case the cloud was clearly seen to curl over, and rapidly pass by
the summit, and yet was neither diminished nor increased in size.
The sun was setting, and a gentle southerly breeze, striking
against the southern side of the rock, mingled its current with the
colder air above; and the vapour was thus condensed: but as the
light wreaths of cloud passed over the ridge, and came within the
influence of the warmer atmosphere of the northern sloping bank,
they were immediately redissolved.

The climate, during the months of May and June, or the beginning of
winter, was delightful. The mean temperature, from observations
taken at nine o’clock, both morning and evening, was only 72
degrees. It often rained heavily, but the drying southerly winds
soon again rendered the walks pleasant. One morning, in the course
of six hours, 1.6 inches of rain fell. As this storm passed over
the forests which surround the Corcovado, the sound produced by the
drops pattering on the countless multitude of leaves was very
remarkable, it could be heard at the distance of a quarter of a
mile, and was like the rushing of a great body of water. After the
hotter days, it was delicious to sit quietly in the garden and
watch the evening pass into night. Nature, in these climes, chooses
her vocalists from more humble performers than in Europe. A small
frog, of the genus Hyla, sits on a blade of grass about an inch
above the surface of the water, and sends forth a pleasing chirp:
when several are together they sing in harmony on different notes.
I had some difficulty in catching a specimen of this frog. The
genus Hyla has its toes terminated by small suckers; and I found
this animal could crawl up a pane of glass, when placed absolutely
perpendicular. Various cicadae and crickets, at the same time, keep
up a ceaseless shrill cry, but which, softened by the distance, is
not unpleasant. Every evening after dark this great concert
commenced; and often have I sat listening to it, until my attention
has been drawn away by some curious passing insect.

At these times the fireflies are seen flitting about from hedge to
hedge. On a dark night the light can be seen at about two hundred
paces distant. It is remarkable that in all the different kinds of
glowworms, shining elaters, and various marine animals (such as the
crustacea, medusae, nereidae, a coralline of the genus Clytia, and
Pyrosoma), which I have observed, the light has been of a
well-marked green colour. All the fireflies, which I caught here,
belonged to the Lampyridae (in which family the English glowworm is
included), and the greater number of specimens were of Lampyris
occidentalis. (2/4. I am greatly indebted to Mr. Waterhouse for his
kindness in naming for me this and many other insects, and giving
me much valuable assistance.) I found that this insect emitted the
most brilliant flashes when irritated: in the intervals, the
abdominal rings were obscured. The flash was almost coinstantaneous
in the two rings, but it was just perceptible first in the anterior
one. The shining matter was fluid and very adhesive: little spots,
where the skin had been torn, continued bright with a slight
scintillation, whilst the uninjured parts were obscured. When the
insect was decapitated the rings remained uninterruptedly bright,
but not so brilliant as before: local irritation with a needle
always increased the vividness of the light. The rings in one
instance retained their luminous property nearly twenty-four hours
after the death of the insect. From these facts it would appear
probable, that the animal has only the power of concealing or
extinguishing the light for short intervals, and that at other
times the display is involuntary. On the muddy and wet gravel-walks
I found the larvae of this lampyris in great numbers: they
resembled in general form the female of the English glowworm. These
larvae possessed but feeble luminous powers; very differently from
their parents, on the slightest touch they feigned death, and
ceased to shine; nor did irritation excite any fresh display. I
kept several of them alive for some time: their tails are very
singular organs, for they act, by a well-fitted contrivance, as
suckers or organs of attachment, and likewise as reservoirs for
saliva, or some such fluid. I repeatedly fed them on raw meat; and
I invariably observed, that every now and then the extremity of the
tail was applied to the mouth, and a drop of fluid exuded on the
meat, which was then in the act of being consumed. The tail,
notwithstanding so much practice, does not seem to be able to find
its way to the mouth; at least the neck was always touched first,
and apparently as a guide.

When we were at Bahia, an elater or beetle (Pyrophorus luminosus,
Illig.) seemed the most common luminous insect. The light in this
case was also rendered more brilliant by irritation. I amused
myself one day by observing the springing powers of this insect,
which have not, as it appears to me, been properly described. (2/5.
Kirby’s “Entomology” volume 2 page 317.) The elater, when placed on
its back and preparing to spring, moved its head and thorax
backwards, so that the pectoral spine was drawn out, and rested on
the edge of its sheath. The same backward movement being continued,
the spine, by the full action of the muscles, was bent like a
spring; and the insect at this moment rested on the extremity of
its head and wing-cases. The effort being suddenly relaxed, the
head and thorax flew up, and in consequence, the base of the
wing-cases struck the supporting surface with such force, that the
insect by the reaction was jerked upwards to the height of one or
two inches. The projecting points of the thorax, and the sheath of
the spine, served to steady the whole body during the spring. In
the descriptions which I have read, sufficient stress does not
appear to have been laid on the elasticity of the spine: so sudden
a spring could not be the result of simple muscular contraction,
without the aid of some mechanical contrivance.

On several occasions I enjoyed some short but most pleasant
excursions in the neighbouring country. One day I went to the
Botanic Garden, where many plants, well known for their great
utility, might be seen growing. The leaves of the camphor, pepper,
cinnamon, and clove trees were delightfully aromatic; and the
bread-fruit, the jaca, and the mango, vied with each other in the
magnificence of their foliage. The landscape in the neighbourhood
of Bahia almost takes its character from the two latter trees.
Before seeing them, I had no idea that any trees could cast so
black a shade on the ground. Both of them bear to the evergreen
vegetation of these climates the same kind of relation which
laurels and hollies in England do to the lighter green of the
deciduous trees. It may be observed that the houses within the
tropics are surrounded by the most beautiful forms of vegetation,
because many of them are at the same time most useful to man. Who
can doubt that these qualities are united in the banana, the
cocoa-nut, the many kinds of palm, the orange, and the bread-fruit
tree?

During this day I was particularly struck with a remark of
Humboldt’s, who often alludes to “the thin vapour which, without
changing the transparency of the air, renders its tints more
harmonious, and softens its effects.” This is an appearance which I
have never observed in the temperate zones. The atmosphere, seen
through a short space of half or three-quarters of a mile, was
perfectly lucid, but at a greater distance all colours were blended
into a most beautiful haze, of a pale French grey, mingled with a
little blue. The condition of the atmosphere between the morning
and about noon, when the effect was most evident, had undergone
little change, excepting in its dryness. In the interval, the
difference between the dew point and temperature had increased from
7.5 to 17 degrees.

On another occasion I started early and walked to the Gavia, or
topsail mountain. The air was delightfully cool and fragrant; and
the drops of dew still glittered on the leaves of the large
liliaceous plants, which shaded the streamlets of clear water.
Sitting down on a block of granite, it was delightful to watch the
various insects and birds as they flew past. The humming-bird seems
particularly fond of such shady retired spots. Whenever I saw these
little creatures buzzing round a flower, with their wings vibrating
so rapidly as to be scarcely visible, I was reminded of the sphinx
moths: their movements and habits are indeed in many respects very
similar.

(PLATE 13. RIO DE JANEIRO.)

Following a pathway I entered a noble forest, and from a height of
five or six hundred feet, one of those splendid views was
presented, which are so common on every side of Rio. At this
elevation the landscape attains its most brilliant tint; and every
form, every shade, so completely surpasses in magnificence all that
the European has ever beheld in his own country, that he knows not
how to express his feelings. The general effect frequently recalled
to my mind the gayest scenery of the Opera-house or the great
theatres. I never returned from these excursions empty-handed. This
day I found a specimen of a curious fungus, called Hymenophallus.
Most people know the English Phallus, which in autumn taints the
air with its odious smell: this, however, as the entomologist is
aware, is to some of our beetles a delightful fragrance. So was it
here; for a Strongylus, attracted by the odour, alighted on the
fungus as I carried it in my hand. We here see in two distant
countries a similar relation between plants and insects of the same
families, though the species of both are different. When man is the
agent in introducing into a country a new species this relation is
often broken: as one instance of this I may mention that the leaves
of the cabbages and lettuces, which in England afford food to such
a multitude of slugs and caterpillars, in the gardens near Rio are
untouched.

During our stay at Brazil I made a large collection of insects. A
few general observations on the comparative importance of the
different orders may be interesting to the English entomologist.
The large and brilliantly-coloured Lepidoptera bespeak the zone
they inhabit, far more plainly than any other race of animals. I
allude only to the butterflies; for the moths, contrary to what
might have been expected from the rankness of the vegetation,
certainly appeared in much fewer numbers than in our own temperate
regions. I was much surprised at the habits of Papilio feronia.
This butterfly is not uncommon, and generally frequents the
orange-groves. Although a high flier, yet it very frequently
alights on the trunks of trees. On these occasions its head is
invariably placed downwards; and its wings are expanded in a
horizontal plane, instead of being folded vertically, as is
commonly the case. This is the only butterfly which I have ever
seen that uses its legs for running. Not being aware of this fact,
the insect, more than once, as I cautiously approached with my
forceps, shuffled on one side just as the instrument was on the
point of closing, and thus escaped. But a far more singular fact is
the power which this species possesses of making a noise. (2/6. Mr.
Doubleday has lately described (before the Entomological Society,
March 3, 1845) a peculiar structure in the wings of this butterfly,
which seems to be the means of its making its noise. He says, “It
is remarkable for having a sort of drum at the base of the fore
wings, between the costal nervure and the subcostal. These two
nervures, moreover, have a peculiar screw-like diaphragm or vessel
in the interior.” I find in Langsdorff’s travels (in the years
1803-7 page 74) it is said, that in the island of St. Catherine’s
on the coast of Brazil, a butterfly called Februa Hoffmanseggi,
makes a noise, when flying away, like a rattle.) Several times when
a pair, probably male and female, were chasing each other in an
irregular course, they passed within a few yards of me; and I
distinctly heard a clicking noise, similar to that produced by a
toothed wheel passing under a spring catch. The noise was continued
at short intervals, and could be distinguished at about twenty
yards’ distance: I am certain there is no error in the observation.

I was disappointed in the general aspect of the Coleoptera. The
number of minute and obscurely coloured beetles is exceedingly
great. (2/7. I may mention, as a common instance of one day’s (June
23rd) collecting, when I was not attending particularly to the
Coleoptera, that I caught sixty-eight species of that order. Among
these, there were only two of the Carabidae, four Brachelytra,
fifteen Rhyncophora, and fourteen of the Chrysomelidae.
Thirty-seven species of Arachnidae, which I brought home, will be
sufficient to prove that I was not paying overmuch attention to the
generally favoured order of Coleoptera.) The cabinets of Europe
can, as yet, boast only of the larger species from tropical
climates. It is sufficient to disturb the composure of an
entomologist’s mind, to look forward to the future dimensions of a
complete catalogue. The carnivorous beetles, or Carabidae, appear
in extremely few numbers within the tropics: this is the more
remarkable when compared to the case of the carnivorous quadrupeds,
which are so abundant in hot countries. I was struck with this
observation both on entering Brazil, and when I saw the many
elegant and active forms of the Harpalidae reappearing on the
temperate plains of La Plata. Do the very numerous spiders and
rapacious Hymenoptera supply the place of the carnivorous beetles?
The carrion-feeders and Brachelytra are very uncommon; on the other
hand, the Rhyncophora and Chrysomelidae, all of which depend on the
vegetable world for subsistence, are present in astonishing
numbers. I do not here refer to the number of different species,
but to that of the individual insects; for on this it is that the
most striking character in the entomology of different countries
depends. The orders Orthoptera and Hemiptera are particularly
numerous; as likewise is the stinging division of the Hymenoptera;
the bees, perhaps, being excepted. A person, on first entering a
tropical forest, is astonished at the labours of the ants:
well-beaten paths branch off in every direction, on which an army
of never-failing foragers may be seen, some going forth, and others
returning, burdened with pieces of green leaf, often larger than
their own bodies.

A small dark-coloured ant sometimes migrates in countless numbers.
One day, at Bahia, my attention was drawn by observing many
spiders, cockroaches, and other insects, and some lizards, rushing
in the greatest agitation across a bare piece of ground. A little
way behind, every stalk and leaf was blackened by a small ant. The
swarm having crossed the bare space, divided itself, and descended
an old wall. By this means many insects were fairly enclosed; and
the efforts which the poor little creatures made to extricate
themselves from such a death were wonderful. When the ants came to
the road they changed their course, and in narrow files reascended
the wall. Having placed a small stone so as to intercept one of the
lines, the whole body attacked it, and then immediately retired.
Shortly afterwards another body came to the charge, and again
having failed to make any impression, this line of march was
entirely given up. By going an inch round, the file might have
avoided the stone, and this doubtless would have happened, if it
had been originally there: but having been attacked, the
lion-hearted little warriors scorned the idea of yielding.

Certain wasp-like insects, which construct in the corners of the
verandahs clay cells for their larvae, are very numerous in the
neighbourhood of Rio. These cells they stuff full of half-dead
spiders and caterpillars, which they seem wonderfully to know how
to sting to that degree as to leave them paralysed but alive, until
their eggs are hatched; and the larvae feed on the horrid mass of
powerless, half-killed victims–a sight which has been described by
an enthusiastic naturalist as curious and pleasing! (2/8. In a
Manuscript in the British Museum by Mr. Abbott, who made his
observations in Georgia; see Mr. A. White’s paper in the “Annals of
Natural History” volume 7 page 472. Lieutenant Hutton has described
a sphex with similar habits in India, in the “Journal of the
Asiatic Society” volume 1 page 555.) I was much interested one day
by watching a deadly contest between a Pepsis and a large spider of
the genus Lycosa. The wasp made a sudden dash at its prey, and then
flew away: the spider was evidently wounded, for, trying to escape,
it rolled down a little slope, but had still strength sufficient to
crawl into a thick tuft of grass. The wasp soon returned, and
seemed surprised at not immediately finding its victim. It then
commenced as regular a hunt as ever hound did after fox; making
short semicircular casts, and all the time rapidly vibrating its
wings and antennae. The spider, though well concealed, was soon
discovered, and the wasp, evidently still afraid of its adversary’s
jaws, after much manoeuvring, inflicted two stings on the under
side of its thorax. At last, carefully examining with its antennae
the now motionless spider, it proceeded to drag away the body. But
I stopped both tyrant and prey. (2/9. Don Felix Azara volume 1 page
175, mentioning a hymenopterous insect, probably of the same genus,
says he saw it dragging a dead spider through tall grass, in a
straight line to its nest, which was one hundred and sixty-three
paces distant. He adds that the wasp, in order to find the road,
every now and then made “demi-tours d’environ trois palmes.”)

The number of spiders, in proportion to other insects, is here
compared with England very much larger; perhaps more so than with
any other division of the articulate animals. The variety of
species among the jumping spiders appears almost infinite. The
genus, or rather family of Epeira, is here characterized by many
singular forms; some species have pointed coriaceous shells, others
enlarged and spiny tibiae. Every path in the forest is barricaded
with the strong yellow web of a species, belonging to the same
division with the Epeira clavipes of Fabricius, which was formerly
said by Sloane to make, in the West Indies, webs so strong as to
catch birds. A small and pretty kind of spider, with very long
fore-legs, and which appears to belong to an undescribed genus,
lives as a parasite on almost every one of these webs. I suppose it
is too insignificant to be noticed by the great Epeira, and is
therefore allowed to prey on the minute insects, which, adhering to
the lines, would otherwise be wasted. When frightened, this little
spider either feigns death by extending its front legs, or suddenly
drops from the web. A large Epeira of the same division with Epeira
tuberculata and conica is extremely common, especially in dry
situations. Its web, which is generally placed among the great
leaves of the common agave, is sometimes strengthened near the
centre by a pair or even four zigzag ribbons, which connect two
adjoining rays. When any large insect, as a grasshopper or wasp, is
caught, the spider, by a dexterous movement, makes it revolve very
rapidly, and at the same time emitting a band of threads from its
spinners, soon envelops its prey in a case like the cocoon of a
silkworm. The spider now examines the powerless victim, and gives
the fatal bite on the hinder part of its thorax; then retreating,
patiently waits till the poison has taken effect. The virulence of
this poison may be judged of from the fact that in half a minute I
opened the mesh, and found a large wasp quite lifeless. This Epeira
always stands with its head downwards near the centre of the web.
When disturbed, it acts differently according to circumstances: if
there is a thicket below, it suddenly falls down; and I have
distinctly seen the thread from the spinners lengthened by the
animal while yet stationary, as preparatory to its fall. If the
ground is clear beneath, the Epeira seldom falls, but moves quickly
through a central passage from one to the other side. When still
further disturbed, it practises a most curious manoeuvre: standing
in the middle, it violently jerks the web, which is attached to
elastic twigs, till at last the whole acquires such a rapid
vibratory movement, that even the outline of the spider’s body
becomes indistinct.

It is well known that most of the British spiders, when a large
insect is caught in their webs, endeavour to cut the lines and
liberate their prey, to save their nets from being entirely
spoiled. I once, however, saw in a hot-house in Shropshire a large
female wasp caught in the irregular web of a quite small spider;
and this spider, instead of cutting the web, most perseveringly
continued to entangle the body, and especially the wings, of its
prey. The wasp at first aimed in vain repeated thrusts with its
sting at its little antagonist. Pitying the wasp, after allowing it
to struggle for more than an hour, I killed it and put it back into
the web. The spider soon returned; and an hour afterwards I was
much surprised to find it with its jaws buried in the orifice
through which the sting is protruded by the living wasp. I drove
the spider away two or three times, but for the next twenty-four
hours I always found it again sucking at the same place. The spider
became much distended by the juices of its prey, which was many
times larger than itself.

I may here just mention, that I found, near St. Fé Bajada, many
large black spiders, with ruby-coloured marks on their backs,
having gregarious habits. The webs were placed vertically, as is
invariably the case with the genus Epeira: they were separated from
each other by a space of about two feet, but were all attached to
certain common lines, which were of great length, and extended to
all parts of the community. In this manner the tops of some large
bushes were encompassed by the united nets. Azara has described a
gregarious spider in Paraguay, which Walckanaer thinks must be a
Theridion, but probably it is an Epeira, and perhaps even the same
species with mine. (2/10. Azara’s “Voyage” volume 1 page 213.) I
cannot, however, recollect seeing a central nest as large as a hat,
in which, during autumn, when the spiders die, Azara says the eggs
are deposited. As all the spiders which I saw were of the same
size, they must have been nearly of the same age. This gregarious
habit, in so typical a genus as Epeira, among insects, which are so
bloodthirsty and solitary that even the two sexes attack each
other, is a very singular fact.

In a lofty valley of the Cordillera, near Mendoza, I found another
spider with a singularly-formed web. Strong lines radiated in a
vertical plane from a common centre, where the insect had its
station; but only two of the rays were connected by a symmetrical
mesh-work; so that the net, instead of being, as is generally the
case, circular, consisted of a wedge-shaped segment. All the webs
were similarly constructed.

(PLATE 14. DARWIN’S PAPILIO FERONIA, 1833, NOW CALLED AGERONIA
FERONIA, 1889.)

 

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