with much caution, that the ants should have no idea of our presence;
if they had, they would cease at the moment their plays and their
occupations, would put themselves in a posture of defence, curve their
abdomen and ejaculate their venom. So much is their attention occupied,
when making preparations for war, that they lose sight of all other
objects.
The ants then are acquainted with labours, combats, I was about to
say, pleasures[4]; they possess signs which are of use to them as
a language, give proofs of their affection for each other, and of
devotedness for their colony, and take care of the females and their
little ones. These are well-known traits of civilization; and if
ants were only of the size of beavers, we should think we could not
sufficiently admire them.
[4] They have also their diseases. I have noticed one extremely
singular. The individuals who are attacked, lose the power of advancing
in a straight line; they cannot proceed but by turning in a very
confined circle, and always in the same direction. A virgin female that
was enclosed in one of my sand boxes was suddenly seized in this way;
she described a circle of an inch in diameter, making about a thousand
turns each hour. She turned constantly during seven days, and when
I visited her in the night, I saw her engaged in the same practice.
I gave her some honey, of which I have every reason to believe she
partook. I once discovered three labourers performing these evolutions,
one of them still possessed the faculty of occasionally moving in a
straight line. I took it up and placed it on my hand; it continued its
gyrations, stopped a moment to taste some honey, and recommenced its
circular journey. The second labourer, which was of the Ash-coloured
species, had one of its antennæ cut; it however escaped, before I had
made upon it the experiments I proposed. The third labourer, belonging
to the Fallow Ants, had suffered no external injury. I am unacquainted
with the cause of this malady; the only one I have observed ants to be
affected with.--A.
CHAP. VI.
OF THE RELATION OF ANTS WITH THE PUCERONS AND GALL INSECTS.
1. _Of the Antennal Language._
Let us return to the important question, relative to the language of
ants. If they have a language, I cannot give too many proofs of it; if
I labour under an error, the following facts, in whatever manner they
may be explained, will plead my excuse.
Imagining that I have not presumed too much upon the justness of my
conclusions, I have been under the necessity of admitting, that ants
possess the means of communicating their different impressions, and
I think this faculty consists, in the striking with their head the
corslet of their companions, and in the contact of their mandibles; but
these are the common signs of which they make use. The antennæ, the
organs of touch, and, perhaps, of some other sense which is unknown to
us, are the principal instruments connected with the language of ants:
their situation in the fore-part of the head, their flexibility, their
construction, which presents a series of articulations, endowed with
extreme sensibility; their close connection with instinct, added to the
observations I made, whilst speaking of the conduct of these insects,
in reference to the females, males, and labourers, induce me to believe
that the antennæ perform the most important office among ants. We have
seen insects frequently use them on the field of battle, to intimate
approaching danger, and to ascertain their own party when mingled with
the enemy; they are also employed, in the interior of the ant-hill,
to warn their companions of the presence of the sun, so favourable
to the development of the larvæ; in their excursions and emigrating,
to indicate their route; in their recruitings, to determine the time
of departure, &c. Let us still see of what further service they are
to these insects. As ants do not possess the art of constructing
magazines, and filling them with provisions, they cannot, like bees,
draw their supply from the cells; they are, therefore, obliged to quit
their habitation: those, who remain at home, expect their food from the
labourers, who are gone abroad to procure it; the latter bring back
small insects, or the bodies of such as they have dismembered. When
they fall in with ripe fruit, or animals of tender flesh, as worms,
lizards, &c. and are not able to convey them to the ant-hill, they
feed upon their juices, and on their return to their habitation, their
stomachs being filled with the liquid provision, they disgorge it in
the mouths of their companions, which is effected in this manner:--the
ant, who experiences hunger, begins striking with both its antennæ,
with an extremely rapid movement, the antennæ of the ant from whom
it waits its supply; it then draws closer, with its mouth open, and
its tongue extended, to receive the fluid, which is observed to pass
from the mouth of one to that of the other: during this operation,
the ant who is receiving aliment, does not cease caressing its kind
friend, by continuing to move its antennæ with great quickness; it also
plays upon the lateral parts of the head of its benefactor, with its
fore-feet, which are furnished with very thick brushes, and which, from
the delicacy and rapidity of their movement, yield in no respect to
the antennæ. The ant, who returns from foraging in the fields, is well
acquainted with the mode of informing its companions of the necessity
under which it lies, of discharging a part of the fluid with which it
is provided, and by the aid of its antennæ, appears to invite them to
come and take their portion; but it does not, in this case, make use
of the fore-feet. This language is well understood by these insects;
even the larvæ, who know how to demand their nourishment, (by raising
their head, as we have before remarked,) erect themselves, and present
their mouths, as soon as they perceive the ant striking with its
antennæ the upper part of their body.
The antennal language would require, without doubt, deep study, should
we be desirous to ascertain every impression which it is susceptible of
communicating. It is, like all the other signs I have observed amongst
ants, founded not upon visible gestures, but upon the contact or
approximation of certain parts; since it was necessary it should prove
of utility in the interior of the ant-hill, where the light of day
never penetrates: hence it happens, that an ant can only be understood
by one of its companions at the same time, but the information which
it conveys, passes from one to the other with extreme rapidity. If
it so happen, that we can prove they know how to impart information
to insects, not of their own species, we must conclude they have been
singularly favoured by nature.
2. _The Intimacy of Ants with the Pucerons._
We know that a great number of vegetables furnish provision to the
_Pucerons_ or _Aphides_. These insects fix themselves upon the leaves,
or small branches, and insinuate their trunk or sucker between the
fibres of the bark, where they find the most substantial nourishment.
A portion of this aliment, shortly after being taken, is expelled,
under the form of small limpid drops, either by the natural passage,
or by two horns, that we commonly observe on the posterior part of the
body. This fluid constitutes the principal support of the ants. We have
already noticed, that they wait the moment when the pucerons eject
this precious manna[1], upon which they (the ants) immediately seize;
but this is the least of their talents, for they know how to obtain it
at any time they wish.
[1] This substance may be frequently seen on the leaves of the oak,
lime, and other trees. It has a glossy appearance, and is remarkably
sweet to the taste. The Abbé Boisier de Sauvages states, that bees will
occasionally wage war with ants, to obtain possession of this honied
secretion.--T.
I observed a branch of a thistle, covered with Brown Ants and pucerons,
and noticed that the latter regulated the time when they discharged
this secretion; but I remarked, that it very rarely passed at the
natural period, and that the pucerons, stationed at some distance from
the ants, scattered it afar off, by a movement somewhat resembling the
kicking or wincing of a horse. How happened it, then, that the ants,
wandering upon the branches, displayed bellies remarkable for their
size, and evidently filled with some kind of liquid. This is what I
learned, by watching closely a single ant, whose movements I am about
to describe. I saw it, at first, pass, without stopping, some pucerons,
which it did not however disturb. It shortly after stationed itself
near one of the smallest, and appeared to caress it, by touching the
extremity of its body, alternately with its antennæ, with an extremely
rapid movement. I saw, with much surprise, the fluid proceed from the
body of the puceron, and the ant take it in its mouth. Its antennæ were
afterwards directed to a much larger puceron than the first, which, on
being caressed after the same manner, discharged the nourishing fluid
in greater quantity, which the ant immediately swallowed: it then
passed to a third which it caressed, like the preceding, by giving it
several gentle blows, with the antennæ, on the posterior extremity
of the body; the liquid was ejected at the same moment, and the ant
lapped it up. It then proceeded to a fourth; this, probably already
exhausted, resisted its action. The ant, who in all probability knew
it had nothing to hope for by remaining there, quitted it for a fifth,
from whom it obtained its expected supply. It now returned, perfectly
contented, to its nest.[2] A small number of such repasts will satisfy
an ant. I still observed those which remained upon the thistle; they
presented me the same scene. From that period, I always found, that
the arrival of the ants, and the striking with their antennæ, preceded
the gift of this liquid, and that the attitude of the pucerons (their
head being lowered,) appeared destined to favour this object. I have a
thousand times witnessed these proceedings, which ants always employ
with success. If, however, they neglect for a long time visiting them,
they (the pucerons) deposit the honey upon the leaves, where the ants
find it on their return.
[2] The more we contemplate the works of nature, and observe the means
she employs in her ordinary operations, the more will our admiration
be excited. Who, for one moment, could suppose, that, as in the
instance before us, what is used as food by one animal, should, on
its passage through the body, become the food of another, and thus
discharge a double office! Who could suppose that excrementitious
matter, of whatever kind, _after supporting myriads of living beings_,
should, on undergoing decomposition, and being separated into its
primary elements, enter into those several combinations, that diffuse a
charming variety around us! How wise is this provision! how admirable
this contrivance! Were it otherwise, we should be perpetually breathing
an atmosphere, charged with noisome effluvia, and living in the very
charnel-house of destruction. In the hands of nature nothing is lost;
all is life and activity: even the death of one being, is but a
commencement of the existence of another. Vapours raised from the sea,
and floating in the upper regions of the air, collect into clouds;
these, on a reduction of temperature, yield their contents to the
thirsty earth: the waters, after fulfilling their appointed office,
pass from the mountains by a thousand rills, into the plains; here, by
their junction, they form rivers, which, taking a circuitous course,
empty themselves into the ocean. Thus we see nature engaged in _running
a perpetual round_, and the waters, after cooling the atmosphere and
refreshing the earth, return to that source whence they originally
sprung.--T.
When the ants come frequently to these insects, the latter appear to
accommodate themselves to their wish, by shortening the period of
their evacuations, which may be ascertained by the size of the drops
they produce; and, in that case, they never eject it to a distance. We
might even say, they are very careful in retaining it, for the purpose
of placing it within their immediate reach. It sometimes happens,
that the ants are too abundant upon the same plant, and, therefore,
exhaust the pucerons that cover it. Under this circumstance, they
vainly attempt to play with their antennæ upon the body of these
insects; they are obliged to wait until the pucerons have replenished
themselves by a further ration drawn from the branches. The pucerons
are not avaricious, and never resist the solicitation of the ants,
when in a state to satisfy them. I have often seen the same individual
grant, successively, several drops of this fluid to different ants, who
appeared extremely anxious to obtain it. The Brown Ant is not the only
ant endowed with this art, although it is certainly one of the most
skilful in procuring, in this way, its subsistence. The Fallow, the
Ash-coloured, the Red, and several other ants, possess, in different
degrees, the power of inducing these insects to deliver over to them
this secretion. The Red Ant displays a singular address in receiving
this little drop. It employs its antennæ, the extremity of which is
a little enlarged, to convey it to its mouth, as if they were real
fingers.
It does not appear that it is by importunity ants obtain from the
pucerons their nourishment. I observed some Fuliginous Ants upon the
branches of an oak, which were loaded with large black pucerons. The
latter were walking backward and forward, and appeared to live in the
best intelligence with the ants: they provided them with honey, but
did not attempt to escape, although they were much more nimble than
those of which I have already spoken. I saw one, in this assembly, that
possessed wings: its wings, which were black, ornamented with two
white rays, together with its size, made it very conspicuous amongst
its companions. I saw several ants very busy and restless around it,
because it approached the other pucerons, from whom they were about
to demand their repast. They proceeded toward it, in great haste,
gave it a few blows with their antennæ, and stationed themselves near
the former. I was, at first, of opinion, that the winged pucerons
embarrassed them; but, in a favourable moment, I observed it to be
struck or caressed by the ants, when it yielded to them the food they
solicited. I have often noticed, since that period, other winged
pucerons delivering to the ants, without restraint, this valuable
liquid; they allowed themselves to be touched by the antennæ of
those insects, remained upon the branch where their companions who
were destitute of wings were stationed, and did not appear to avoid
the ants, whose number one would suppose would inconvenience them.
This proves that the neighbourhood of the ants is agreeable to the
pucerons, since those who might easily withdraw from their visits,
prefer resting among them, bestowing upon them what is superfluous of
their nourishment.
I have noticed the same occurrence with respect to the greater part
of the ants of this country. The largest pay their visits also to the
pucerons. One would be astonished to see how they treat them, and with
what delicacy they invite them with their antennæ (which are different
from those of the Red Ants, and more slender at the extremity than
elsewhere) to deliver over the honey.[3] I am not acquainted with any
ants, to whom the art of obtaining from the pucerons their subsistence,
is unknown: we might even venture to affirm that these insects have
been created for their use.
[3] We know that these ants which have two knots on the abdominal
fillet, have their antennæ enlarged; in those of the other classes,
they are filiform and setaceous.--A.
3. _Of the Relation of Ants with the Gall Insects._
We know that the gall insects as well as the pucerons, station
themselves on the leaves and branches of trees, to suck their juices.
The mouth and the sexual parts are applied against the tree; the
orifice, destined to reject the excess of their nourishment, is placed
on the back. The ants are attracted by the gall insects as well as the
pucerons: I am not the first to have observed it. It has been long
known that the kermes, and the cochineal insects, which are generally
allied to our gall insects, are always accompanied by ants, but we
were unacquainted with the reason for this intimacy. It had never
been remarked, that the gall insects delivered over to them, like the
pucerons, a considerable portion of the fluids they extract.
M. de Reaumur himself believed, that the puncture made upon the tree
by the gall insects, continued to pour forth a fluid after they had
withdrawn their sucker, and that the ants came up immediately to lap
the juice which transuded; but this conjecture, however probable it
then appeared, has not been verified. These insects, which had for so
many years escaped our notice, were at all times known by the ants to
be beings endowed with life and sensation. I was very much astonished
when I saw, for the first time, an ant approach a gall insect, and
perform with its antennæ, on its lower extremity, the same manœuvres,
which it executed in respect to the pucerons. After having a few
moments caressed this insect, I saw proceed from its back, a large drop
of fluid, which the ant immediately lapped up. I observed the same
occurrence, with reference to other gall insects on the same tree,
during several seasons. They were stationed in great number upon an
enlarged part of the trunk. The ants came there constantly to receive
their provisions, which was fully confirmed by my observing these
insects upon an orange tree, where I saw the ants obtain from them
their food in the same manner. We can only compare the movements of
ants upon this occasion, to the play of the fingers in a shake upon the
piano-forte.
The kermes, like the pucerons, eject this fluid to a distance when the
ants are not present to receive it; this, however, but rarely happens.
The gall insects of the vine, the peach, and the mulberry-tree, never
failed presenting me with the same spectacle; which gave me some
general ideas respecting the relation which exists between the instinct
of these insects and that of ants. That the pucerons and the gall
insects experience pleasure, when caressed in this way by the ants;
that it is an advantage to them to be earlier rid of their secretions;
or that there really exists between each, some kind of language, is
still one of those questions upon which we cannot well decide: but
we shall not the less admire the manner in which ants procure their
subsistence. This fluid is to them an inexhaustible treasure. It
will be enough, to be convinced of this truth, to station one’s-self
near an oak covered with these insects, where we shall, soon after,
observe thousands of ants ascending and descending the trunk. All those
ascending have small bellies, and walk nimbly; those, on the contrary,
descending, have their abdomen swoln, transparent, full of the fluid
obtained from these insects, and do not move but with difficulty.
4. _The almost Human Industry of Ants._
There are ants that scarcely ever quit their abode; we neither observe
them moving towards trees or their fruit; they do not even go in chace
of other insects; they are, notwithstanding, extremely common in our
meadows and orchards. I allude to the Yellow Ants, called by the common
people Red Ants, and which would merit the surname of _souterraines_.
They are two lines in length, their body is of a pale yellow colour,
slightly transparent, and covered with hair.
I knew where all the other ants sought and obtained their nourishment;
but I could not ascertain what these did to exist, and what aliment
they could furnish themselves with, without quitting their habitation;
when, one day, having turned up the earth of which their nest was
composed, to discover if they had any provision, I found it to contain
the pucerons. I saw them at the roots of the grass which surrounded
the ant-hill. They were assembled in considerable numbers, and were
of different species: the most common, were of a flesh colour and of
a round form; others were white, and had the body more flattened; but
they were of the same genus. There were also some that were green
and violet coloured, others with black and green rays; the latter
stood higher upon their legs, and were much longer. Some were removed
to a great depth, attached to the deeper part of the roots; others
were wandering about in the midst of the ants, either in the upper
or under-ground chambers. The ants appeared to seize the favourable
moment for taking their food; they acted in the ordinary manner, and
always with the same success. This clearly explained, why the ants of
this species did not quit their abode, since they had, without leaving
it, all that was necessary for their support.