of the Yellow Ants, where I always found the pucerons. They may be
readily seen after warm rains; for they at that time keep near the
surface of the ground: the plants upon which they are stationed may be
then readily plucked up by the roots, without crushing these insects,
which happens when the earth is too dry. I soon found that the Yellow
Ants were extremely jealous of these insects; they took them often in
their mouths, and carried them to the bottom of the nest; at other
times, they brought them up among them, or followed them with much
solicitude. I profited by the information I had acquired of their way
of life, so as to nourish, at my own residence, one of their colonies.
I placed the ants in a glazed box, with their pucerons, leaving in the
earth I gave them the roots of some plants, whose branches vegetated
without. I watered from time to time the ant-hill, and in this manner,
the plants, the pucerons, and the ants themselves, found in this
apparatus abundant nourishment. The ants made no attempt to escape;
they appeared to have nothing to desire; they took care of their larvæ
and females, with the same affection as in their own nest; they also
paid great attention to the pucerons, and never injured them. The
latter did not seem to labour under the slightest fear; they allowed
themselves to be carried from place to place, and rested in the spot
chosen by their guardians. When the ants wished to displace them, they
began caressing them with their antennæ, hoping thereby, to induce them
to abandon the roots, or to withdraw their trunk from the cavity in
which it was inserted; they afterwards took them up gently in their
mandibles, and carried them with the same care as the larvæ of their
own species. I witnessed the same ant remove, successively, three of
these insects, much larger than itself, and convey them to a darkened
chamber.[4] There was one which made a long resistance, probably by
not being enabled, at the moment, to withdraw its trunk, which might
have been buried deeply in the wood. I was much amused in observing
the various attempts made by this ant, to induce it to quit its hold;
it caressed and seized it alternately, until it at length yielded
to its wishes. The ants do not employ this gentle method, when they
labour under an apprehension that these insects may be taken away from
them by the ants of another species, living near their habitation, or
when we happen to tread too heavily on the grass under which they are
concealed, for they then seize upon them directly, and carry them off
to the under-ground chambers. I have seen the ants of two neighbouring
nests disputing about their pucerons; when the ants of one nest were
enabled to enter the habitation of their neighbours, they purloined
these insects, which were, after a time, often recovered by their
original possessors. The ants know full well the value of these little
animals, which, it would appear, had been created for them;--they
constitute their sole wealth, an ant-hill being more or less rich,
as it is more or less provided with pucerons; they are in fact their
cattle, their cows, their goats, &c. Who could have imagined that the
ants were a pastoral tribe! But a question here presents itself of some
interest:--Do the pucerons, which I have constantly found in nests of
this species, come of their own free will to reside there, or are they
brought thither by the ants? the latter appears to me most probable,
for the ants are in the habit of carrying them continually from place
to place, and are the individuals who receive all the advantages
attending this relation.
[4] I have often been surprised at the strength, as well as address,
occasionally displayed by ants. At the entrance of a nest of Red
Ants, I placed a large house-fly; several ants came out from time to
time, to examine it. But what was my surprise, to see a solitary ant
attempt the removal of so large a body: it caught hold of one of the
wings forcibly by its pincers, and exerted all its strength to drag
it along. This it did with apparent ease, where the ground was not
uneven; but on meeting any obstruction, and finding the _dragging
system_ useless, it quitted its post for the opposite station, and
overcame the resistance by _pushing_. In this way it removed the fly
to a considerable distance. A difficulty at length presented itself,
which I thought insuperable. The ant, however, did not relax in its
exertions: after attempting to _drag_ it for some time, it endeavoured
to _push_ it forward, going alternately to the several parts of the
body. All these efforts were useless. In this emergency it seized the
fly in its mouth, and by a sudden jerk lifted it from the ground, and
thus overcame the impediment.--“The Mahometans hold, on the relation of
Thevenot (as mentioned by Messrs. Kirby and Spence), that one of the
animals in Paradise is Solomon’s Ant, which, when all creatures, in
obedience to him, brought him presents, dragged before him a locust,
and was therefore preferred before all others, because it had brought a
creature so much bigger than itself.”--T.
I am strongly inclined to believe, that the Yellow Ants, and all those
who are endowed with the same industry, go in search of these insects
through the subterranean galleries they have formed between the roots;
that they find them scattered among the grass, and bring them to the
nest. I cannot conceive, if this be not the case, why there should be
so many of these insects in ant-hills, for they are not equally common
elsewhere. I have seldom discovered them under the grass, but they were
surrounded by Yellow Ants, who arrive at their haunts by subterranean
passages, and who, probably, convey them to their nest in the autumn.
They often seized upon them in my presence, and withdrew with them
by some obscure path, which proves that these insects are at their
complete disposal.
It is more particularly during the bad weather, that they assemble them
at the bottom of the nest. In the summer, we more frequently find them
at the foot of the plant, contiguous to the ant-hill, where the plants
suffer less from drought than when growing upon the very nest; but this
is nearly the same as if they were enclosed with the ants, since their
habitation extends more within the earth than without.
Four or five species of ants keep pucerons in their abode; but less
constantly, and in much smaller number, than the Yellow Ants, as they
obtain a portion of their subsistence from those inhabiting trees.
There are some, who reach the branches, loaded with these insects,
under a covered way of earth, leading directly from their nest. Here
the ants are as well furnished with food as if they kept the pucerons
in their own dwelling; and as often as they wish to bring these insects
to their nest, they can accomplish it without the knowledge of other
ants, and without incurring any risk. The Red, the Brown, the Turf Ant,
and another species, excessively small, are always, during Autumn,
Winter, and Spring, in the possession of pucerons. The latter, which
we might name the microscopic ant, for it is only half a line in
length, equally finds pucerons proportioned to its size: they are of
a white colour, and a little larger than the ant itself. The pucerons
then are the domestic animals of the ants: the latter collect these
insects around them, as we collect those animals which administer to
our wants, near the habitation in which we reside. The animals which
are subject to our controul, know the voice of man; the pucerons and
the gall insects understand, as it should seem, the language of ants,
and furnish them with their aliment, unconstrained. There are several
other insects which live among ants, although they do not appear to be
of any service to them; these are, woodlice, earwigs, and certain larvæ
of the scarabæi. The ants, from being accustomed to their sight, permit
their residence among them; they never do them any injury, which is
the more singular, as ants pass in general for beings of an irritable
disposition.
But what is invariable, what I have always witnessed respecting the
Yellow Ants, and what it is of some importance to know, is, that they
have pucerons in their nests, and that they never destroy them: they,
on the contrary, bring them together, to enjoy more conveniently, the
fluid which these insects furnish them.
If these ants display, in this respect, an industry worthy of man,
there are others, whose proceedings are not less remarkable, and who
appear to take possession of the pucerons, which feed on the branches
of trees, and the stalks of herbaceous plants. The ants, extremely
jealous in preserving these insects, and especially those who reside
near them, will not suffer any strangers to come and dispute with them
the nourishment they offer. They drive them off with their mandibles,
become uneasy and restless, and pass over the branch with every mark
of anger. They sometimes take these insects in their mouths, to guard
them from the attacks of other ants: more frequently, they station a
guard around them; and when they are enabled to do so, they put them
out of the reach of their rivals, by a very ingenious method, of which
I have seen many examples.
I observed one day on the stem of a thistle, a little sphere or
lodgment, which the ants had fabricated with earth; they quitted it by
an extremely narrow aperture formed in the bottom, descended along the
stalk, and passed into a neighbouring ant-hill. I destroyed one part
of this tent, constructed almost in air, to see the interior, which
consisted of a little hall, whose sides of a vaulted form, were smooth
and compact. The ants had availed themselves of the form of the plant,
to sustain this edifice; the stem passed through the centre of the
apartment, and its leaves composed the whole of the _carpentry_. This
retreat contained an extensive family of pucerons, from whom the Brown
Ants peaceably received their food, sheltered from the rain and sun,
and safe from the invasion of foreign ants; no insect could disturb
them, and the pucerons were not exposed to the attacks of their various
enemies. I admired this trait of their industry; but I soon observed it
on a more extensive scale, and with greater interest, among ants of a
different species.
Some Red Ants had constructed around the foot of a thistle a cylinder
of earth, two inches and a half in length, by one and a half in
breadth. The ant-hill lay below, and communicated directly with this
tunnel. I took the branch, with its contents, and found that portion of
the stem comprised in the tunnel, furnished with pucerons. I presently
saw go out, by the opening which I had made at its base, a few ants,
who seemed much astonished at the light appearing in that place. I
perceived they were living there with their larvæ; they transported
them in a hurry, to the upper part of the cylinder, which had not been
injured. It was here they kept at their disposal, their joint stock of
pucerons, and here they nourished their little ones.
In another spot, several stems of a thistle, loaded with pucerons,
rose from the very centre of an ant-hill, inhabited by Brown Ants,
who, availing themselves of the particular disposition of the leaves
of this plant, had constructed around the branches, several little
oblong houses, where they came to procure their food. On my destroying
one of these houses, the ants carried off immediately into their nest
the little animals they so much valued. A few days after, I saw it
repaired, and the cattle brought back to their paddock. These houses
are not always constructed close to the ground: I saw one once five
feet above the surface, which merits being described; it consisted
of a short blackish tunnel, which surrounded a small branch of a
poplar-tree, at that place where it quitted the trunk. The ants
arrived at this spot by passing through the interior of the tree, which
was hollow, and thus screened from observation, they reached their
pucerons by an opening at the beginning of the branch. The tunnel
was formed of decayed wood, and of the earth about the tree. I saw
several ants engaged in bringing pellets in their mouths, to repair
the breaches I had made. These proceedings are by no means of common
occurrence; we cannot attribute them to an habitual routine.
There are some ants who receive their nourishment from the pucerons
inhabiting the common plantain: they are generally stationed under
the flower; but when this falls to the ground, and the stem withers,
which happens about the end of August, they retire for shelter under
the radical leaves of the plant; the ants follow, and enclose them, by
_walling_ up with moist earth all the space between the ground and the
margin of the leaves; they afterwards excavate the ground, to have
more room to approach these insects, and pass from thence to their
habitation, by covered galleries.
5. _Resources of the Ants during Winter._
I am naturally led to speak in this place, of the manner in which ants
subsist in winter, since we have relinquished the opinion that they
amass wheat and other grain, and that they gnaw the corn to hinder it
from germinating. We have endeavoured to explain their preservation,
by supposing them to fall into a state of torpor at this period. They,
in fact, become torpid during the intense cold, but when the season is
not very severe, the depth of their nest guards them from the effects
of the frost: they do not become torpid, unless the temperature is
reduced to the second degree of Reaumur under the freezing point, (27°
Fahrenheit.) I have occasionally seen them walking upon the snow,
engaged in their customary avocations. In so reduced a temperature,
they would be exposed to the horrors of famine, were they not supplied
with food by the pucerons, who, by an admirable concurrence of
circumstances, which we cannot attribute to chance, become torpid at
precisely the same degree of cold as the ants, and recover from this
state also, at the same time: the ants, therefore, always find them
when they need them.
Those ants that do not possess the knowledge of the mode of assembling
these insects, are, at least, acquainted with their retreat; they
follow them to the feet of the trees, and the branches of the shrubs
they before frequented, pass at the first degree of frost along the
hedges, following the paths which conduct to these insects, and bring
back to the republic a small quantity of honey; a very little sufficing
for their support in winter.
As soon as the ants recover from their torpid state, they venture forth
to procure their food. The aliment contained in their stomach is, on
their return, equally distributed to their companions. These juices
scarcely evaporate, during this season, owing to the thickness of the
horny rings investing the body. I have known ants preserve, during a
considerable time, their internal stock of provisions, when they could
not impart it to their companions. When the cold increases in a gradual
manner, (and this is commonly what the ants experience who are screened
from it by a thick wall of earth,) they collect and lie upon each other
by thousands, and appear all hooked together. Is this done, in order to
provide themselves a little heat? I presume this to be the case, but
our thermometers are not sufficiently delicate to indicate if this be
really the fact.
6. _Of the Eggs of the Pucerons._
The pucerons, which are viviparous in the summer, are oviparous during
Autumn. This very remarkable fact is here most fully confirmed.[5] One
day, in November, anxious to know if the Yellow Ants began to bury
themselves in their subterranean chambers, I destroyed, with care,
one of their habitations, story by story. I had not advanced far in
this attempt, when I discovered an apartment containing an assemblage
of little eggs, which were for the most part of the colour of ebony.
Several ants surrounded, and appeared to take great care of them, and
endeavoured, as quickly as possible, to convey them from my sight.
I seized upon this chamber, its inhabitants, and the treasure it
contained.
[5] Although these insects are both oviparous and viviparous, yet
this is not the greatest singularity in their history, for they will
produce, as fully confirmed by Bonnet and other celebrated naturalists,
several young in succession, without intercourse with the male insect.
The common gnat, it is asserted, will produce young, and these, in
their turn, will give birth to others, down to the sixth generation,
without further intercourse with the male. Huber, the father of our
present author, so well known to us from his extensive discoveries in
natural history, thinks, that one impregnation is sufficient to render
fertile all the eggs which a queen bee may produce in the whole course
of her life, usually about two years. And Mons. Audibert has known a
female spider produce young, for several successive generations, from
one single impregnation of the male. The circumstance of the _Aphides_,
or _Pucerons_, being oviparous or viviparous, seems to depend upon the
prevailing temperature. Mr. Curtis having remarked the same species to
be oviparous in the open air, which when sheltered from the wind, in
a green-house, was viviparous. The wood-louse, it has been remarked,
sometimes produces its young in the state of an egg, sometimes brings
them forth perfectly alive. Redi also mentions a similar circumstance,
in his work on the generation of insects, in reference to some of the
flies he describes.--T.
The ants did not abandon these eggs to make their escape; a stronger
instinct retained them: they hastened to conceal them under the small
dwelling, which I held in my hand, and when I reached home, I drew them
from it, to observe them more attentively. Viewed with a microscope,
they appeared nearly of the form of ants’ eggs, but their colour was
entirely different; the greater part were black; others were of a
cloudy yellow. I found them in several ant-hills, and obtained them
of different degrees in shade; they were not all black and yellow;
some were brown, of a slight, and also of a brilliant red and white;
others were of a colour less distinct, as a straw colour, greyish, &c.
I remarked they were not of the same colour at both extremities.
To observe them more closely, I placed them in the cover of a box faced
with glass; they were collected in a heap, like the eggs of ants; their
guardians seemed to value them highly; after having visited them,
they placed one part in the earth, but I witnessed the attention they
bestowed upon the rest: they approached them slightly separating their
pincers, passed their tongue between each, extended them, then walked
alternately over them, depositing, I believe, a liquid substance as
they proceeded. They appeared to treat them exactly as if they were
eggs of their own species; they touched them with their antennæ, and
frequently carried them in their mouths; they did not quit these eggs
a single instant; they took them up, turned them, and after having
surveyed them with affectionate regard, conveyed them, with extreme
tenderness, to the little chamber of earth I had placed at their
disposal. They were not, however, the eggs of ants; we know that these
are extremely white, becoming transparent, as they increase in age,
but never acquire a colour essentially different.[6] I was, for a
long time, unacquainted with the origin of those of which I have just
spoken, and by chance, discovered they contained little pucerons; but
it was not these individual eggs I saw them quit, it was other eggs,
which were a little larger, found in the nests of Yellow Ants, and of
a particular species. On opening the ant-hill, I discovered several
chambers, containing a great number of brown eggs, the ants were
extremely jealous of them, carrying them away, and quickly too, to the
bottom of the nest, disputing and contending for them with a zeal which
left me no doubt of the strong attachment with which they regard them.
[6] Gould has taken notice of these black eggs, which he considers to
be the female eggs of ants: here, however, he labours under a mistake,
for they are evidently the eggs of the _Aphides_, or _Pucerons_. We
learn from Mr. Kirby, that in a nest of yellow ants, which fell under
his observation, he saw near the surface a parcel of the eggs of the
Aphides, and these he knew by their black colour.--T.
Desirous of conciliating their interests, as well as my own, I took the
ants and their treasure, and placed them in such a manner that I might
easily observe them. These eggs were never abandoned. The ants took the
same care of them as the former. The following day I saw one of these
eggs open, and a puceron fully formed, having a large trunk, quit it.
I knew it to be a puceron of the oak: the others were disclosed a few
days after, and the greater number in my presence. They set immediately
about sucking the juice from some branches of the tree I gave them, and
the ants now found, within their reach, a recompense for their care
and attention.
The ant-hill, whence these eggs had been taken, was situated at the
foot of an oak, which readily accounts for their existence in that
place. I discovered them in the spring; the pucerons which quitted them
were very large, for insects just born, but they had not yet obtained
their full size. M. Bonnet, to whom we are indebted for many important
discoveries upon the pucerons and their generation, speaks of their
eggs, which he has often seen affixed to the branches of trees; he
believes that the insect, in a state nearly perfect, quits the body of
its mother in that covering which shelters it from the cold in winter,
and that it is not, as other germs are, in the egg, surrounded by food,
by means of which it is developed and supported. It is nothing more
than an asylum of which the pucerons born at another season have no
need: it is on this account some are produced naked, others enveloped
in a covering. The mothers are not then truly oviparous, since their
young are almost as perfect as they ever will be, in the asylum in
which Nature has placed them at their birth. M. Bonnet vainly attempted
to preserve these kind of eggs in his chamber until the spring; he
imagines, that to have attained this end, they should have been kept in
a certain degree of humidity, which would have happened to them in a
state of nature.
It appears, then, that ants know every thing that is necessary to the
preservation of these eggs; they pass their tongue constantly over
them, and invest them with a glutinous matter, which retains them
together. They, in consequence, are preserved until the period when the
pucerons quit them: they employ then the same means to preserve their
covey, if I may use this expression, that M. Bonnet supposed would
preserve these eggs, and secure their disclosure in the spring. We
have reason to believe that this celebrated man would have admired with
us this part of their industry, if natural history had not lost in him
her most worthy contemplator.
CHAPTER VII.
FIRST HISTORICAL SKETCH OF THE AMAZON ANTS.
We have hitherto treated only of labouring ants, of societies composed
of three sorts of individuals, of operations equally divided among
the labourers, and of transient wars, without any fixed purpose, or
having only for their object common defence. The Amazon Ants present us
manners and habits totally different,--republics peculiarly constituted
and organised,--character dissimilar,--wars regularly instituted,--in
a word, a separate history; and of which no author has yet given any
account.
On the 17th June, 1804, whilst walking in the environs of Geneva,
between four and five in the evening, I observed close at my feet,
traversing the road, a legion of Rufescent Ants.[1]
[1] For a description of this species see the Appendix.
They moved in a body with considerable rapidity, and occupied a space
of from eight to ten inches in length, by three or four in breadth. In
a few minutes they quitted the road, passed a thick hedge, and entered
a pasture ground, where I followed them. They wound along the grass
without straggling, and their column remained unbroken, notwithstanding
the obstacles they had to surmount; at length they approached a nest,
inhabited by dark Ash-coloured Ants, the dome of which rose above
the grass, at a distance of twenty feet from the hedge. Some of its
inhabitants were guarding the entrance; but, on the discovery of an
approaching army, darted forth upon the advanced guard. The alarm
spread at the same moment in the interior, and their companions came
forth in numbers from their underground residence. The Rufescent
Ants, the bulk of whose army lay only at the distance of two paces,
quickened their march to arrive at the foot of the ant-hill; the whole
battalion, in an instant, fell upon and overthrew the Ash-coloured
Ants, who, after a short, but obstinate conflict, retired to the bottom
of their nest. The Rufescent Ants now ascended the hillock, collected
in crowds on the summit, and took possession of the principal avenues,
leaving some of their companions to work an opening in the side of the
ant-hill with their teeth. Success crowned their enterprise, and by
the newly made breach the remainder of the army entered. Their sojourn
was, however, of short duration, for in three or four minutes they
returned by the same apertures which gave them entrance, each bearing
off in its mouth a larva or a pupa; they retraced the route by which
they had arrived, and proceeded one after another, without order or
regularity.[2] The whole army might be readily distinguished in the
grass, by the contrast afforded by the Rufescent Ants, and the white
eggs and pupæ they had captured. They repassed the hedge and the road,
in the place they had previously crossed it, and then directed their
course through a field of ripened corn, where I experienced the regret
of not being able to follow them.
[2] The tactics of these marauders vary with the enemy they have to
contend with; in this instance, conscious of carrying off their booty,
without further opposition from the Ash-coloured Ants, the army no
longer keeps in rank, but separates into straggling parties, each
hastening by a different route, to deposit their spoil in the common
treasury; but, when these intrepid adventurers attack a nest of mining
ants, and return successful, they are then obliged, from the known
spirit and courage of the latter, to keep close order, and march in
a body to the very gates of their citadel; as it not unfrequently
happens, they are followed and harassed the whole way by the mining
ants, who leave no exertion untried to recover their treasure.--T.
I now retraced my steps towards the scene of the recent assault, and
there found a small number of Ash-coloured labourers, perched upon
the stalks of plants, holding in their mouths the few larvæ they had
rescued from pillage; these they shortly carried back to their former
station.
This feature, so prominent in the history of Rufescent Ants, of whose
real name I was then ignorant, induced me to give them the appellation
of Amazon or Legionary Ants, as being most analogous to their martial
character; these denominations I still retain; therefore, when I speak
of Rufescent, Amazon, or Legionary Ants, it will be understood that I
am treating of the same species.[3]