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When laying-time is at hand, the Spider changes her residence;
she
abandons her web in excellent condition; she does not return to
it. Whoso
will can take possession of the house. The hour has come to found
the
family-establishment. But where? The Spider knows right well; I am
in
the dark. Mornings are spent in fruitless searches. In vain I
ransack
the bushes that carry the webs: I never find aught that realizes
my
hopes.
I learn the secret at last. I chance upon a web which,
though deserted,
is not yet dilapidated, proving that it has been but lately
quitted.
Instead of hunting in the brushwood whereon it rests, let us inspect
the
neighbourhood, to a distance of a few paces. If these contain a
low,
thick cluster, the nest is there, hidden from the eye. It carries
an
authentic certificate of its origin, for the mother invariably
occupies
it.
By this method of investigation, far from the
labyrinth-trap, I become
the owner of as many nests as are needed to satisfy
my curiosity. They
do not by a long way come up to my idea of the maternal
talent. They are
clumsy bundles of dead leaves, roughly drawn together with
silk threads.
Under this rude covering is a pouch of fine texture containing
the egg-
casket, all in very bad condition, because of the inevitable
tears
incurred in its extrication from the brushwood. No, I shall not be
able
to judge of the artist's capacity by these rags and tatters.
The
insect, in its buildings, has its own architectural rules, rules
as
unchangeable as anatomical peculiarities. Each group builds according
to
the same set of principles, conforming to the laws of a very
elementary
system of aesthetics; but often circumstances beyond the
architect's
control--the space at her disposal, the unevenness of the site,
the
nature of the material and other accidental causes--interfere with
the
worker's plans and disturb the structure. Then virtual regularity
is
translated into actual chaos; order degenerates into disorder.
We
might discover an interesting subject of research in the type adopted
by each
species when the work is accomplished without hindrances. The
Banded Epeira
weaves the wallet of her eggs in the open, on a slim branch
that does not get
in her way; and her work is a superbly artistic jar.
The Silky Epeira also
has all the elbow-room she needs; and her
paraboloid is not without
elegance. Can the Labyrinth Spider, that other
spinstress of accomplished
merit, be ignorant of the precepts of beauty
when the time comes for her to
weave a tent for her offspring? As yet,
what I have seen of her work is but
an unsightly bundle. Is that all she
can do?
I look for better things
if circumstances favour her. Toiling in the
midst of a dense thicket, among
a tangle of dead leaves and twigs, she
may well produce a very inaccurate
piece of work; but compel her to
labour when free from all impediment: she
will then--I am convinced of it
beforehand--apply her talents without
constraint and show herself an
adept in the building of graceful
nests.
As laying-time approaches, towards the middle of August, I instal
half-a-
dozen Labyrinth Spiders in large wire-gauze cages, each standing in
an
earthen pan filled with sand. A sprig of thyme, planted in the
centre,
will furnish supports for the structure, together with the
trellis-work
of the top and sides. There is no other furniture, no dead
leaves, which
would spoil the shape of the nest if the mother were minded to
employ
them as a covering. By way of provision, Locusts, every day. They
are
readily accepted, provided they be tender and not too large.
The
experiment works perfectly. August is hardly over before I am in
possession
of six nests, magnificent in shape and of a dazzling
whiteness. The latitude
of the workshop has enabled the spinstress to
follow the inspiration of her
instinct without serious obstacles; and the
result is a masterpiece of
symmetry and elegance, if we allow for a few
angularities demanded by the
suspension-points.
It is an oval of exquisite white muslin, a diaphanous
abode wherein the
mother must make a long stay to watch over the brood. The
size is nearly
that of a Hen's egg. The cabin is open at either
end. The
front-entrance broadens into a gallery; the back-entrance tapers
into a
funnel-neck. I fail to see the object of this neck. As for the
opening
in front, which is wider, this is, beyond a doubt, a
victualling-door. I
see the Spider, at intervals, standing here on the
look-out for the
Locust, whom she consumes outside, taking care not to soil
the spotless
sanctuary with corpses.
The structure of the nest is not
without a certain similarity to that of
the home occupied during the
hunting-season. The passage at the back
represents the funnel-neck, that ran
almost down to the ground and
afforded an outlet for flight in case of grave
danger. The one in front,
expanding into a mouth kept wide open by cords
stretched backwards and
forwards, recalls the yawning gulf into which the
victims used to fall.
Every part of the old dwelling is repeated: even the
labyrinth, though
this, it is true, is on a much smaller scale. In front of
the
bell-shaped mouth is a tangle of threads wherein the passers-by
are
caught. Each species, in this way, possesses a primary
architectural
model which is followed as a whole, in spite of altered
conditions. The
animal knows its trade thoroughly, but it does not know and
will never
know aught else, being incapable of originality.
Now this
palace of silk, when all is said, is nothing more than a
guard-
house. Behind the soft, milky opalescence of the wall glimmers the
egg-
tabernacle, with its form vaguely suggesting the star of some order
of
knighthood. It is a large pocket, of a splendid dead-white, isolated
on
every side by radiating pillars which keep it motionless in the centre
of
the tapestry. These pillars are about ten in number and are slender
in
the middle, expanding at one end into a conical capital and at the
other
into a base of the same shape. They face one another and mark
the
position of the vaulted corridors which allow free movement in
every
direction around the central chamber. The mother walks gravely to
and
fro under the arches of her cloisters, she stops first here, then
there;
she makes a lengthy auscultation of the egg-wallet; she listens to
all
that happens inside the satin wrapper. To disturb her would
be
barbarous.
For a closer examination, let us use the dilapidated
nests which we
brought from the fields. Apart from its pillars, the
egg-pocket is an
inverted conoid, reminding us of the work of the Silky
Epeira. Its
material is rather stout; my pincers, pulling at it, do not tear
it
without difficulty. Inside the bag there is nothing but an
extremely
fine, white wadding and, lastly, the eggs, numbering about a
hundred and
comparatively large, for they measure a millimetre and a half.
{37} They
are very pale amber-yellow beads, which do not stick together and
which
roll freely as soon as I remove the swan's-down shroud. Let us
put
everything into a glass-tube to study the hatching.
We will now
retrace our steps a little. When laying-time comes, the
mother forsakes her
dwelling, her crater into which her falling victims
dropped, her labyrinth in
which the flight of the Midges was cut short;
she leaves intact the apparatus
that enabled her to live at her ease.
Thoughtful of her natural duties, she
goes to found another establishment
at a distance. Why at a
distance?
She has still a few long months to live and she needs
nourishment. Were
it not better, then, to lodge the eggs in the immediate
neighbourhood of
the present home and to continue her hunting with the
excellent snare at
her disposal? The watching of the nest and the easy
acquisition of
provender would go hand in hand. The Spider is of another
opinion; and I
suspect the reason.
The sheet-net and the labyrinth
that surmounts it are objects visible
from afar, owing to their whiteness and
the height whereat they are
placed. Their scintillation in the sun, in
frequented paths, attracts
Mosquitoes and Butterflies, like the lamps in our
rooms and the fowler's
looking-glass. Whoso comes to look at the bright
thing too closely dies
the victim of his curiosity. There is nothing better
for playing upon
the folly of the passer-by, but also nothing more dangerous
to the safety
of the family.
Harpies will not fail to come running at
this signal, showing up against
the green; guided by the position of the web,
they will assuredly find
the precious purse; and a strange grub, feasting on
a hundred new-laid
eggs, will ruin the establishment. I do not know these
enemies, not
having sufficient materials at my disposal for a register of
the
parasites; but, from indications gathered elsewhere, I suspect
them.
The Banded Epeira, trusting to the strength of her stuff, fixes her
nest
in the sight of all, hangs it on the brushwood, taking no
precautions
whatever to hide it. And a bad business it proves for her. Her
jar
provides me with an Ichneumon {38} possessed of the inoculating
larding-
pin: a _Cryptus_ who, as a grub, had fed on Spiders' eggs. Nothing
but
empty shells was left inside the central keg; the germs were
completely
exterminated. There are other Ichneumon-flies, moreover, addicted
to
robbing Spiders' nests; a basket of fresh eggs is their
offspring's
regular food.
Like any other, the Labyrinth Spider dreads
the scoundrelly advent of the
pickwallet; she provides for it and, to shield
herself against it as far
as possible, chooses a hiding-place outside her
dwelling, far removed
from the tell-tale web. When she feels her ovaries
ripen, she shifts her
quarters; she goes off at night to explore the
neighbourhood and seek a
less dangerous refuge. The points selected are, by
preference, the low
brambles dragging along the ground, keeping their dense
verdure during
the winter and crammed with dead leaves from the oaks hard
by. Rosemary-
tufts, which gain in thickness what they lose in height on
the
unfostering rock, suit her particularly. This is where I usually
find
her nest, not without long seeking, so well is it hidden.
So far,
there is no departure from current usage. As the world is full
of creatures
on the prowl for tender mouthfuls, every mother has her
apprehensions; she
also has her natural wisdom, which advises her to
establish her family in
secret places. Very few neglect this precaution;
each, in her own manner,
conceals the eggs she lays.
In the case of the Labyrinth Spider, the
protection of the brood is
complicated by another condition. In the vast
majority of instances, the
eggs, once lodged in a favourable spot, are
abandoned to themselves, left
to the chances of good or ill fortune. The
Spider of the brushwood, on
the contrary, endowed with greater maternal
devotion, has, like the Crab
Spider, to mount guard over hers until they
hatch.
With a few threads and some small leaves joined together, the Crab
Spider
builds, above her lofty nest, a rudimentary watch-tower where she
stays
permanently, greatly emaciated, flattened into a sort of wrinkled
shell
through the emptying of her ovaries and the total absence of
food. And
this mere shred, hardly more than a skin that persists in living
without
eating, stoutly defends her egg-sack, shows fight at the approach of
any
tramp. She does not make up her mind to die until the little ones
are
gone.
The Labyrinth Spider is better treated. After laying her
eggs, so far
from becoming thin, she preserves an excellent appearance and a
round
belly. Moreover, she does not lose her appetite and is always
prepared
to bleed a Locust. She therefore requires a dwelling with a
hunting-box
close to the eggs watched over. We know this dwelling, built in
strict
accordance with artistic canons under the shelter of my
cages.
Remember the magnificent oval guard-room, running into a vestibule
at
either end; the egg-chamber slung in the centre and isolated on
every
side by half a score of pillars; the front-hall expanding into a
wide
mouth and surmounted by a network of taut threads forming a
trap. The
semi-transparency of the walls allows us to see the Spider engaged
in her
household affairs. Her cloister of vaulted passages enables her
to
proceed to any point of the star-shaped pouch containing the
eggs.
Indefatigable in her rounds, she stops here and there; she fondly
feels
the satin, listens to the secrets of the wallet. If I shake the net
at
any point with a straw, she quickly runs up to enquire what is
happening.
Will this vigilance frighten off the Ichneumon and other lovers
of
omelettes? Perhaps so. But, though this danger be averted, others
will
come when the mother is no longer there.
Her attentive watch does
not make her overlook her meals. One of the
Locusts whereof I renew the
supply at intervals in the cages is caught in
the cords of the great
entrance-hall. The Spider arrives hurriedly,
snatches the giddy-pate and
disjoints his shanks, which she empties of
their contents, the best part of
the insect. The remainder of the
carcass is afterwards drained more or less,
according to her appetite at
the time. The meal is taken outside the
guard-room, on the threshold,
never indoors.
These are not capricious
mouthfuls, serving to beguile the boredom of the
watch for a brief while;
they are substantial repasts, which require
several sittings. Such an
appetite astonishes me, after I have seen the
Crab Spider, that no less
ardent watcher, refuse the Bees whom I give her
and allow herself to die of
inanition. Can this other mother have so
great a need as that to eat? Yes,
certainly she has; and for an
imperative reason.
At the beginning of
her work, she spent a large amount of silk, perhaps
all that her reserves
contained; for the double dwelling--for herself and
for her offspring--is a
huge edifice, exceedingly costly in materials;
and yet, for nearly another
month, I see her adding layer upon layer both
to the wall of the large cabin
and to that of the central chamber, so
much so that the texture, which at
first was translucent gauze, becomes
opaque satin. The walls never seem
thick enough; the Spider is always
working at them. To satisfy this lavish
expenditure, she must
incessantly, by means of feeding, fill her silk-glands
as and when she
empties them by spinning. Food is the means whereby she
keeps the
inexhaustible factory going.
A month passes and, about the
middle of September, the little ones hatch,
but without leaving their
tabernacle, where they are to spend the winter
packed in soft wadding. The
mother continues to watch and spin,
lessening her activity from day to
day. She recruits herself with a
Locust at longer intervals; she sometimes
scorns those whom I myself
entangle in her trap. This increasing
abstemiousness, a sign of
decrepitude, slackens and at last stops the work of
the spinnerets.
For four or five weeks longer, the mother never ceases
her leisurely
inspection-rounds, happy at hearing the new-born Spiders
swarming in the
wallet. At length, when October ends, she clutches her
offspring's
nursery and dies withered. She has done all that maternal
devotion can
do; the special providence of tiny animals will do the
rest. When spring
comes, the youngsters will emerge from their snug
habitation, disperse
all over the neighbourhood by the expedient of the
floating thread and
weave their first attempts at a labyrinth on the tufts of
thyme.
Accurate in structure and neat in silk-work though they be, the
nests of
the caged captives do not tell us everything; we must go back to
what
happens in the fields, with their complicated conditions. Towards
the
end of December, I again set out in search, aided by all my
youthful
collaborators. We inspect the stunted rosemaries along the edge of
a
path sheltered by a rocky, wooded slope; we lift the branches that
spread
over the ground. Our zeal is rewarded with success. In a couple
of
hours, I am the owner of some nests.
Pitiful pieces of work are
they, injured beyond recognition by the
assaults of the weather! It needs
the eyes of faith to see in these
ruins the equivalent of the edifices built
inside my cages. Fastened to
the creeping branch, the unsightly bundle lies
on the sand heaped up by
the rains. Oak-leaves, roughly joined by a few
threads, wrap it all
round. One of these leaves, larger than the others,
roofs it in and
serves as a scaffolding for the whole of the ceiling. If we
did not see
the silky remnants of the two vestibules projecting and feel a
certain
resistance when separating the parts of the bundle, we might take
the
thing for a casual accumulation, the work of the rain and the
wind.
Let us examine our find and look more closely into its
shapelessness.
Here is the large room, the maternal cabin, which rips as the
coating of
leaves is removed; here are the circular galleries of the
guard-room;
here are the central chamber and its pillars, all in a fabric
of
immaculate white. The dirt from the damp ground has not penetrated
to
this dwelling protected by its wrapper of dead leaves.
Now open the
habitation of the offspring. What is this? To my utter
astonishment, the
contents of the chamber are a kernel of earthy matters,
as though the muddy
rain-water had been allowed to soak through. Put
aside that idea, says the
satin wall, which itself is perfectly clean
inside. It is most certainly the
mother's doing, a deliberate piece of
work, executed with minute care. The
grains of sand are stuck together
with a cement of silk; and the whole
resists the pressure of the fingers.
If we continue to unshell the
kernel, we find, below this mineral layer,
a last silken tunic that forms a
globe around the brood. No sooner do we
tear this final covering than the
frightened little ones run away and
scatter with an agility that is singular
at this cold and torpid season.
To sum up, when working in the natural
state, the Labyrinth Spider builds
around the eggs, between two sheets of
satin, a wall composed of a great
deal of sand and a little silk. To stop
the Ichneumon's probe and the
teeth of the other ravagers, the best thing
that occurred to her was this
hoarding which combines the hardness of flint
with the softness of
muslin.
This means of defence seems to be pretty
frequent among Spiders. Our own
big House Spider, _Tegenaria domestica_,
encloses her eggs in a globule
strengthened with a rind of silk and of
crumbly wreckage from the mortar
of the walls. Other species, living in the
open under stones, work in
the same way. They wrap their eggs in a mineral
shell held together with
silk. The same fears have inspired the same
protective methods.
Then how comes it that, of the five mothers reared in
my cages, not one
has had recourse to the clay rampart? After all, sand
abounded: the pans
in which the wire-gauze covers stood were full of it. On
the other hand,
under normal conditions, I have often come across nests
without any
mineral casing. These incomplete nests were placed at some
height from
the ground, in the thick of the brushwood; the others, on the
contrary,
those supplied with a coating of sand, lay on the
ground.
The method of the work explains these differences. The concrete
of our
buildings is obtained by the simultaneous manipulation of gravel
and
mortar. In the same way, the Spider mixes the cement of the silk
with
the grains of sand; the spinnerets never cease working, while the
legs
fling under the adhesive spray the solid materials collected in
the
immediate neighbourhood. The operation would be impossible if,
after
cementing each grain of sand, it were necessary to stop the work of
the
spinnerets and go to a distance to fetch further stony
elements. Those
materials have to be right under her legs; otherwise the
Spider does
without and continues her work just the same.
In my cages,
the sand is too far off. To obtain it, the Spider would
have to leave the
top of the dome, where the nest is being built on its
trellis-work support;
she would have to come down some nine inches. The
worker refuses to take
this trouble, which, if repeated in the case of
each grain, would make the
action of the spinnerets too irksome. She
also refuses to do so when, for
reasons which I have not fathomed, the
site chosen is some way up in the tuft
of rosemary. But, when the nest
touches the ground, the clay rampart is
never missing.
Are we to see in this fact proof of an instinct capable of
modification,
either making for decadence and gradually neglecting what was
the
ancestors' safeguard, or making for progress and advancing,
hesitatingly,
towards perfection in the mason's art? No inference is
permissible in
either direction. The Labyrinth Spider has simply taught us
that
instinct possesses resources which are employed or left latent
according
to the conditions of the moment. Place sand under her legs and
the
spinstress will knead concrete; refuse her that sand, or put it out
of
her reach, and the Spider will remain a simple silk-worker, always
ready,
however, to turn mason under favourable conditions. The aggregate
of
things that come within the observer's scope proves that it were mad
to
expect from her any further innovations, such as would utterly change
her
methods of manufacture and cause her, for instance, to abandon her
cabin,
with its two entrance-halls and its star-like tabernacle, in favour
of
the Banded Epeira's pear-shaped gourd.
CHAPTER XVI: THE
CLOTHO SPIDER
She is named Durand's Clotho (_Clotho Durandi_, LATR.),
in memory of him
who first called attention to this particular Spider. To
enter on
eternity under the safe-conduct of a diminutive animal which saves
us
from speedy oblivion under the mallows and rockets is no
contemptible
advantage. Most men disappear without leaving an echo to repeat
their
name; they lie buried in forgetfulness, the worst of
graves.
Others, among the naturalists, benefit by the designation given
to this
or that object in life's treasure-house: it is the skiff wherein
they
keep afloat for a brief while. A patch of lichen on the bark of an
old
tree, a blade of grass, a puny beastie: any one of these hands down
a
man's name to posterity as effectively as a new comet. For all
its
abuses, this manner of honouring the departed is eminently
respectable.
If we would carve an epitaph of some duration, what could we
find better
than a Beetle's wing-case, a Snail's shell or a Spider's
web? Granite is
worth none of them. Entrusted to the hard stone, an
inscription becomes
obliterated; entrusted to a Butterfly's wing, it is
indestructible.
'Durand,' therefore, by all means.
But why drag in
'Clotho'? Is it the whim of a nomenclator, at a loss for
words to denote the
ever-swelling tide of beasts that require
cataloguing? Not entirely. A
mythological name came to his mind, one
which sounded well and which,
moreover, was not out of place in
designating a spinstress. The Clotho of
antiquity is the youngest of the
three Fates; she holds the distaff whence
our destinies are spun, a
distaff wound with plenty of rough flocks, just a
few shreds of silk and,
very rarely, a thin strand of gold.
Prettily
shaped and clad, as far as a Spider can be, the Clotho of the
naturalists is,
above all, a highly talented spinstress; and this is the
reason why she is
called after the distaff-bearing deity of the infernal
regions. It is a pity
that the analogy extends no further. The
mythological Clotho, niggardly with
her silk and lavish with her coarse
flocks, spins us a harsh existence; the
eight-legged Clotho uses naught
but exquisite silk. She works for herself;
the other works for us, who
are hardly worth the trouble.
Would we
make her acquaintance? On the rocky slopes in the oliveland,
scorched and
blistered by the sun, turn over the flat stones, those of a
fair size;
search, above all, the piles which the shepherds set up for a
seat whence to
watch the sheep browsing amongst the lavender below. Do
not be too easily
disheartened: the Clotho is rare; not every spot suits
her. If fortune smile
at last upon our perseverance, we shall see,
clinging to the lower surface of
the stone which we have lifted, an
edifice of a weather-beaten aspect, shaped
like an over-turned cupola and
about the size of half a tangerine
orange. The outside is encrusted or
hung with small shells, particles of
earth and, especially, dried
insects.
The edge of the cupola is
scalloped into a dozen angular lobes, the
points of which spread and are
fixed to the stone. In between these
straps is the same number of spacious
inverted arches. The whole
represents the Ishmaelite's camel-hair tent, but
upside down. A flat
roof, stretched between the straps, closes the top of
the dwelling.
Then where is the entrance? All the arches of the edge
open upon the
roof; not one leads to the interior. The eye seeks in vain;
there is
nothing to point to a passage between the inside and the
outside. Yet
the owner of the house must go out from time to time, were it
only in
search of food; on returning from her expedition, she must go in
again.
How does she make her exits and her entrances? A straw will tell us
the
secret.
Pass it over the threshold of the various
arches. Everywhere, the
searching straw encounters resistance; everywhere,
it finds the place
rigorously closed. But one of the scallops, differing in
no wise from
the others in appearance, if cleverly coaxed, opens at the edge
into two
lips and stands slightly ajar. This is the door, which at once
shuts
again of its own elasticity. Nor is this all: the Spider, when
she
returns home, often bolts herself in, that is to say, she joins
and
fastens the two leaves of the door with a little silk.
The Mason
Mygale is no safer in her burrow, with its lid
undistinguishable from the
soil and moving on a hinge, than is the Clotho
in her tent, which is
inviolable by any enemy ignorant of the device. The
Clotho, when in danger,
runs quickly home; she opens the chink with a
touch of her claw, enters and
disappears. The door closes of itself and
is supplied, in case of need, with
a lock consisting of a few threads. No
burglar, led astray by the
multiplicity of arches, one and all alike,
will ever discover how the
fugitive vanished so suddenly.
While the Clotho displays a more simple
ingenuity as regards her
defensive machinery, she is incomparably ahead of
the Mygale in the
matter of domestic comfort. Let us open her cabin. What
luxury! We are
taught how a Sybarite of old was unable to rest, owing to the
presence of
a crumpled rose-leaf in his bed. The Clotho is quite as
fastidious. Her
couch is more delicate than swan's-down and whiter than the
fleece of the
clouds where brood the summer storms. It is the ideal
blanket. Above is
a canopy or tester of equal softness. Between the two
nestles the
Spider, short-legged, clad in sombre garments, with five yellow
favours
on her back.
Rest in this exquisite retreat demands perfect
stability, especially on
gusty days, when sharp draughts penetrate beneath
the stone. This
condition is admirably fulfilled. Take a careful look at
the habitation.
The arches that gird the roof with a balustrade and bear the
weight of
the edifice are fixed to the slab by their extremities. Moreover,
from
each point of contact, there issues a cluster of diverging threads
that
creep along the stone and cling to it throughout their length,
which
spreads afar. I have measured some fully nine inches long. These are
so
many cables; they represent the ropes and pegs that hold the Arab's
tent
in position. With such supports as these, so numerous and
so
methodically arranged, the hammock cannot be torn from its bearings
save
by the intervention of brutal methods with which the Spider need
not
concern herself, so seldom do they occur.
Another detail attracts
our attention: whereas the interior of the house
is exquisitely clean, the
outside is covered with dirt, bits of earth,
chips of rotten wood, little
pieces of gravel. Often there are worse
things still: the exterior of the
tent becomes a charnel-house. Here,
hung up or embedded, are the dry
carcasses of Opatra, Asidae and other
Tenebrionidae {39} that favour
underrock shelters; segments of Iuli, {40}
bleached by the sun; shells of
Pupae, {41} common among the stones; and,
lastly, Snail-shells, selected from
among the smallest.
These relics are obviously, for the most part,
table-leavings, broken
victuals. Unversed in the trapper's art, the Clotho
courses her game and
lives upon the vagrants who wander from one stone to
another. Whoso
ventures under the slab at night is strangled by the hostess;
and the
dried-up carcass, instead of being flung to a distance, is hung to
the
silken wall, as though the Spider wished to make a bogey-house of
her
home. But this cannot be her aim. To act like the ogre who hangs
his
victims from the castle battlements is the worst way to disarm
suspicion
in the passers-by whom you are lying in wait to
capture.
There are other reasons which increase our doubts. The shells
hung up
are most often empty; but there are also some occupied by the
Snail,
alive and untouched. What can the Clotho do with a _Pupa cinerea_,
a
_Pupa quadridens_ and other narrow spirals wherein the animal retreats
to
an inaccessible depth? The Spider is incapable of breaking
the
calcareous shell or of getting at the hermit through the
opening. Then
why should she collect those prizes, whose slimy flesh is
probably not to
her taste? We begin to suspect a simple question of ballast
and balance.
The House Spider, or _Tegenaria domestica_, prevents her web,
spun in a
corner of the wall, from losing its shape at the least breath of
air, by
loading it with crumbling plaster and allowing tiny fragments of
mortar
to accumulate. Are we face to face with a similar process? Let us
try
experiment, which is preferable to any amount of conjecture.
To
rear the Clotho is not an arduous undertaking; we are not obliged to
take the
heavy flagstone, on which the dwelling is built, away with us. A
very simple
operation suffices. I loosen the fastenings with my pocket-
knife. The
Spider has such stay-at-home ways that she very rarely makes
off. Besides, I
use the utmost discretion in my rape of the house. And
so I carry away the
building, together with its owner, in a paper bag.
The flat stones, which
are too heavy to move and which would occupy too
much room upon my table, are
replaced either by deal disks, which once
formed part of cheese-boxes, or by
round pieces of cardboard. I arrange
each silken hammock under one of these
by itself, fastening the angular
projections, one by one, with strips of
gummed paper. The whole stands
on three short pillars and gives a very fair
imitation of the underrock
shelter in the form of a small dolmen. Throughout
this operation, if you
are careful to avoid shocks and jolts, the Spider
remains indoors.
Finally, each apparatus is placed under a wire-gauze,
bell-shaped cage,
which stands in a dish filled with sand.
We can have
an answer by the next morning. If, among the cabins swung
from the ceilings
of the deal or cardboard dolmens, there be one that is
all dilapidated, that
was seriously knocked out of shape at the time of
removal, the Spider
abandons it during the night and instals herself
elsewhere, sometimes even on
the trellis-work of the wire cage.
The new tent, the work of a few hours,
attains hardly the diameter of a
two-franc piece. It is built, however, on
the same principles as the old
manor-house and consists of two thin sheets
laid one above the other, the
upper one flat and forming a tester, the lower
curved and pocket-shaped.
The texture is extremely delicate: the least trifle
would deform it, to
the detriment of the available space, which is already
much reduced and
only just sufficient for the recluse.
Well, what has
the Spider done to keep the gossamer stretched, to steady
it and to make it
retain its greatest capacity? Exactly what our static
treatises would advise
her to do: she has ballasted her structure, she
has done her best to lower
its centre of gravity. From the convex
surface of the pocket hang long
chaplets of grains of sand strung
together with slender silken cords. To
these sandy stalactites, which
form a bushy beard, are added a few heavy
lumps hung separately and lower
down, at the end of a thread. The whole is a
piece of ballast-work, an
apparatus for ensuring equilibrium and
tension.
The present edifice, hastily constructed in the space of a
night, is the
frail rough sketch of what the home will afterwards
become. Successive
layers will be added to it; and the partition-wall will
grow into a thick
blanket capable of partly retaining, by its own weight, the
requisite
curve and capacity. The Spider now abandons the stalactites of
sand,
which were used to keep the original pocket stretched, and
confines
herself to dumping down on her abode any more or less heavy
object,
mainly corpses of insects, because she need not look for these and
finds
them ready to hand after each meal. They are weights, not trophies;
they
take the place of materials that must otherwise be collected from
a
distance and hoisted to the top. In this way, a breastwork is
obtained
that strengthens and steadies the house. Additional equilibrium is
often
supplied by tiny shells and other objects hanging a long way
down.
What would happen if one robbed an old dwelling, long since
completed, of
its outer covering? In case of such a disaster, would the
Spider go back
to the sandy stalactites, as a ready means of restoring
stability? This
is easily ascertained. In my hamlets under wire, I select a
fair-sized
cabin. I strip the exterior, carefully removing any foreign
body. The
silk reappears in its original whiteness. The tent looks
magnificent,
but seems to me too limp.
This is also the Spider's
opinion. She sets to work, next evening, to
put things right. And
how? Once more with hanging strings of sand. In
a few nights, the silk bag
bristles with a long, thick beard of
stalactites, a curious piece of work,
excellently adapted to maintain the
web in an unvaried curve. Even so are
the cables of a suspension-bridge
steadied by the weight of the
superstructure.
Later, as the Spider goes on feeding, the remains of the
victuals are
embedded in the wall, the sand is shaken and gradually drops
away and the
home resumes its charnel-house appearance. This brings us to
the same
conclusion as before: the Clotho knows her statics; by means
of
additional weights, she is able to lower the centre of gravity and
thus
to give her dwelling the proper equilibrium and capacity.
Now
what does she do in her softly-wadded home? Nothing, that I know of.
With a
full stomach, her legs luxuriously stretched over the downy
carpet, she does
nothing, thinks of nothing; she listens to the sound of
earth revolving on
its axis. It is not sleep, still less is it waking;
it is a middle state
where naught prevails save a dreamy consciousness of
well-being. We
ourselves, when comfortably in bed, enjoy, just before we
fall asleep, a few
moments of bliss, the prelude to cessation of thought
and its train of
worries; and those moments are among the sweetest in our
lives. The Clotho
seems to know similar moments and to make the most of
them.
If I push
open the door of the cabin, invariably I find the Spider lying
motionless, as
though in endless meditation. It needs the teasing of a
straw to rouse her
from her apathy. It needs the prick of hunger to
bring her out of doors;
and, as she is extremely temperate, her
appearances outside are few and far
between. During three years of
assiduous observation, in the privacy of my
study, I have not once seen
her explore the domain of the wire cage by
day. Not until a late hour at
night does she venture forth in quest of
victuals; and it is hardly
feasible to follow her on her
excursions.
Patience once enabled me to find her, at ten o'clock in the
evening,
taking the air on the flat roof of her house, where she was
doubtless
waiting for the game to pass. Startled by the light of my candle,
the
lover of darkness at once returned indoors, refusing to reveal any of
her
secrets. Only, next day, there was one more corpse hanging from the
wall
of the cabin, a proof that the chase was successfully resumed after
my
departure.
The Clotho, who is not only nocturnal, but also
excessively shy, conceals
her habits from us; she shows us her works, those
precious historical
documents, but hides her actions, especially the laying,
which I estimate
approximately to take place in October. The sum total of
the eggs is
divided into five or six small, flat, lentiform pockets, which,
taken
together, occupy the greater part of the maternal home. These
capsules
have each their own partition-wall of superb white satin, but they
are so
closely soldered, both together and to the floor of the house, that it
is
impossible to part them without tearing them, impossible, therefore,
to
obtain them separately. The eggs in all amount to about a
hundred.
The mother sits upon the heap of pockets with the same devotion
as a
brooding hen. Maternity has not withered her. Although decreased
in
bulk, she retains an excellent look of health; her round belly and
her
well-stretched skin tell us from the first that her part is not
yet
wholly played.
The hatching takes place early. November has not
arrived before the
pockets contain the young: wee things clad in black, with
five yellow
specks, exactly like their elders. The new-born do not leave
their
respective nurseries. Packed close together, they spend the whole of
the
wintry season there, while the mother, squatting on the pile of
cells,
watches over the general safety, without knowing her family other than
by
the gentle trepidations felt through the partitions of the tiny
chambers.
The Labyrinth Spider has shown us how she maintains a permanent
sitting
for two months in her guard-room, to defend, in case of need, the
brood
which she will never see. The Clotho does the same during eight
months,
thus earning the right to set eyes for a little while on her
family
trotting around her in the main cabin and to assist at the final
exodus,
the great journey undertaken at the end of a thread.
When the
summer heat arrives, in June, the young ones, probably aided by
their mother,
pierce the walls of their cells, leave the maternal tent,
of which they know
the secret outlet well, take the air on the threshold
for a few hours and
then fly away, carried to some distance by a
funicular aeroplane, the first
product of their spinning-mill.
The elder Clotho remains behind, careless
of this emigration which leaves
her alone. She is far from being faded
indeed, she looks younger than
ever. Her fresh colour, her robust appearance
suggest great length of
life, capable of producing a second family. On this
subject I have but
one document, a pretty far-reaching one, however. There
were a few
mothers whose actions I had the patience to watch, despite the
wearisome
minutiae of the rearing and the slowness of the result. These
abandoned
their dwellings after the departure of their young; and each went
to
weave a new one for herself on the wire net-work of the cage.
They
were rough-and-ready summaries, the work of a night. Two hangings,
one above
the other, the upper one flat, the lower concave and ballasted
with
stalactites of grains of sand, formed the new home, which,
strengthened daily
by fresh layers, promised to become similar to the old
one. Why does the
Spider desert her former mansion, which is in no way
dilapidated--far from
it--and still exceedingly serviceable, as far as
one can judge? Unless I am
mistaken, I think I have an inkling of the
reason.
The old cabin,
comfortably wadded though it be, possesses serious
disadvantages: it is
littered with the ruins of the children's nurseries.
These ruins are so
close-welded to the rest of the home that my forceps
cannot extract them
without difficulty; and to remove them would be an
exhausting business for
the Clotho and possibly beyond her strength. It
is a case of the resistance
of Gordian knots, which not even the very
spinstress who fastened them is
capable of untying. The encumbering
litter, therefore, will
remain.
If the Spider were to stay alone, the reduction of space, when
all is
said, would hardly matter to her: she wants so little room, merely
enough
to move in! Besides, when you have spent seven or eight months in
the
cramping presence of those bedchambers, what can be the reason of
a
sudden need for greater space? I see but one: the Spider requires
a
roomy habitation, not for herself--she is satisfied with the
smallest
den--but for a second family. Where is she to place the pockets of
eggs,
if the ruins of the previous laying remain in the way? A new
brood
requires a new home. That, no doubt, is why, feeling that her
ovaries
are not yet dried up, the Spider shifts her quarters and founds a
new
establishment.
The facts observed are confined to this change of
dwelling. I regret
that other interests and the difficulties attendant upon
a long
upbringing did not allow me to pursue the question and definitely
to
settle the matter of the repeated layings and the longevity of
the
Clotho, as I did in that of the Lycosa.
Before taking leave of
this Spider, let us glance at a curious problem
which has already been set by
the Lycosa's offspring. When carried for
seven months on the mother's back,
they keep in training as agile
gymnasts without taking any nourishment. It
is a familiar exercise for
them, after a fall, which frequently occurs, to
scramble up a leg of
their mount and nimbly to resume their place in the
saddle. They expend
energy without receiving any material
sustenance.
The sons of the Clotho, the Labyrinth Spider and many others
confront us
with the same riddle: they move, yet do not eat. At any period
of the
nursery stage, even in the heart of winter, on the bleak days of
January,
I tear the pockets of the one and the tabernacle of the other,
expecting
to find the swarm of youngsters lying in a state of complete
inertia,
numbed by the cold and by lack of food. Well, the result is
quite
different. The instant their cells are broken open, the anchorites
run
out and flee in every direction as nimbly as at the best moments of
their
normal liberty. It is marvellous to see them scampering about. No
brood
of Partridges, stumbled upon by a Dog, scatters more
promptly.
Chicks, while still no more than tiny balls of yellow fluff,
hasten up at
the mother's call and scurry towards the plate of rice. Habit
has made
us indifferent to the spectacle of those pretty little animal
machines,
which work so nimbly and with such precision; we pay no attention,
so
simple does it all appear to us. Science examines and looks at
things
differently. She says to herself:
'Nothing is made with
nothing. The chick feeds itself; it consumes or
rather it assimilates and
turns the food into heat, which is converted
into energy.'
Were any
one to tell us of a chick which, for seven or eight months on
end, kept
itself in condition for running, always fit, always brisk,
without taking the
least beakful of nourishment from the day when it left
the egg, we could find
no words strong enough to express our incredulity.
Now this paradox of
activity maintained without the stay of food is
realized by the Clotho Spider
and others.
I believe I have made it sufficiently clear that the young
Lycosae take
no food as long as they remain with their mother. Strictly
speaking,
doubt is just admissible, for observation is needs dumb as to what
may
happen earlier or later within the mysteries of the burrow. It
seems
possible that the repleted mother may there disgorge to her family a
mite
of the contents of her crop. To this suggestion the Clotho undertakes
to
make reply.
Like the Lycosa, she lives with her family; but the
Clotho is separated
from them by the walls of the cells in which the little
ones are
hermetically enclosed. In this condition, the transmission of
solid
nourishment becomes impossible. Should any one entertain a theory
of
nutritive humours cast up by the mother and filtering through
the
partitions at which the prisoners might come and drink, the
Labyrinth
Spider would at once dispel the idea. She dies a few weeks after
her
young are hatched; and the children, still locked in their
satin
bed-chamber for the best part of the year, are none the less
active.
Can it be that they derive sustenance from the silken
wrapper? Do they
eat their house? The supposition is not absurd, for we
have seen the
Epeirae, before beginning a new web, swallow the ruins of the
old. But
the explanation cannot be accepted, as we learn from the Lycosa,
whose
family boasts no silky screen. In short, it is certain that the
young,
of whatever species, take absolutely no nourishment.
Lastly, we
wonder whether they may possess within themselves reserves
that come from the
egg, fatty or other matters the gradual combustion of
which would be
transformed into mechanical force. If the expenditure of
energy were of but
short duration, a few hours or a few days, we could
gladly welcome this idea
of a motor viaticum, the attribute of every
creature born into the
world. The chick possesses it in a high degree:
it is steady on its legs, it
moves for a little while with the sole aid
of the food wherewith the egg
furnishes it; but soon, if the stomach is
not kept supplied, the centre of
energy becomes extinct and the bird
dies. How would the chick fare if it
were expected, for seven or eight
months without stopping, to stand on its
feet, to run about, to flee in
the face of danger? Where would it stow the
necessary reserves for such
an amount of work?
The little Spider, in
her turn, is a minute particle of no size at all.
Where could she store
enough fuel to keep up mobility during so long a
period? The imagination
shrinks in dismay before the thought of an atom
endowed with inexhaustible
motive oils.
We must needs, therefore, appeal to the immaterial, in
particular to heat-
rays coming from the outside and converted into movement
by the organism.
This is nutrition of energy reduced to its simplest
expression: the
motive heat, instead of being extracted from the food, is
utilized
direct, as supplied by the sun, which is the seat of all
life. Inert
matter has disconcerting secrets, as witness radium; living
matter has
secrets of its own, which are more wonderful still. Nothing tells
us
that science will not one day turn the suspicion suggested by the
Spider
into an established truth and a fundamental theory of
physiology.
APPENDIX: THE GEOMETRY OF THE EPEIRA'S
WEB
I find myself confronted with a subject which is not only
highly
interesting, but somewhat difficult: not that the subject is obscure;
but
it presupposes in the reader a certain knowledge of geometry: a
strong
meat too often neglected. I am not addressing geometricians, who
are
generally indifferent to questions of instinct, nor
entomological
collectors, who, as such, take no interest in mathematical
theorems; I
write for any one with sufficient intelligence to enjoy the
lessons which
the insect teaches.
What am I to do? To suppress this
chapter were to leave out the most
remarkable instance of Spider industry; to
treat it as it should be
treated, that is to say, with the whole armoury of
scientific formulae,
would be out of place in these modest pages. Let us
take a middle
course, avoiding both abstruse truths and complete
ignorance.
Let us direct our attention to the nets of the Epeirae,
preferably to
those of the Silky Epeira and the Banded Epeira, so plentiful
in the
autumn, in my part of the country, and so remarkable for their
bulk. We
shall first observe that the radii are equally spaced; the angles
formed
by each consecutive pair are of perceptibly equal value; and this
in
spite of their number, which in the case of the Silky Epeira exceeds
two
score. We know by what strange means the Spider attains her ends
and
divides the area wherein the web is to be warped into a large number
of
equal sectors, a number which is almost invariable in the work of
each
species. An operation without method, governed, one might imagine, by
an
irresponsible whim, results in a beautiful rose-window worthy of
our
compasses.
We shall also notice that, in each sector, the various
chords, the
elements of the spiral windings, are parallel to one another
and
gradually draw closer together as they near the centre. With the
two
radiating lines that frame them they form obtuse angles on one side
and
acute angles on the other; and these angles remain constant in the
same
sector, because the chords are parallel.
There is more than this:
these same angles, the obtuse as well as the
acute, do not alter in value,
from one sector to another, at any rate so
far as the conscientious eye can
judge. Taken as a whole, therefore, the
rope-latticed edifice consists of a
series of cross-bars intersecting the
several radiating lines obliquely at
angles of equal value.
By this characteristic we recognize the
'logarithmic spiral.'
Geometricians give this name to the curve which
intersects obliquely, at
angles of unvarying value, all the straight lines or
'radii vectores'
radiating from a centre called the 'Pole.' The Epeira's
construction,
therefore, is a series of chords joining the intersections of
a
logarithmic spiral with a series of radii. It would become merged
in
this spiral if the number of radii were infinite, for this would
reduce
the length of the rectilinear elements indefinitely and change
this
polygonal line into a curve.
To suggest an explanation why this
spiral has so greatly exercised the
meditations of science, let us confine
ourselves for the present to a few
statements of which the reader will find
the proof in any treatise on
higher geometry.
The logarithmic spiral
describes an endless number of circuits around its
pole, to which it
constantly draws nearer without ever being able to
reach it. This central
point is indefinitely inaccessible at each
approaching turn. It is obvious
that this property is beyond our sensory
scope. Even with the help of the
best philosophical instruments, our
sight could not follow its interminable
windings and would soon abandon
the attempt to divide the invisible. It is a
volute to which the brain
conceives no limits. The trained mind, alone, more
discerning than our
retina, sees clearly that which defies the perceptive
faculties of the
eye.
The Epeira complies to the best of her ability
with this law of the
endless volute. The spiral revolutions come closer
together as they
approach the pole. At a given distance, they stop abruptly;
but, at this
point, the auxiliary spiral, which is not destroyed in the
central
region, takes up the thread; and we see it, not without some
surprise,
draw nearer to the pole in ever-narrowing and scarcely
perceptible
circles. There is not, of course, absolute mathematical
accuracy, but a
very close approximation to that accuracy. The Epeira winds
nearer and
nearer round her pole, so far as her equipment, which, like our
own, is
defective, will allow her. One would believe her to be thoroughly
versed
in the laws of the spiral. |
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