THE CIGALE. THE EGGS AND THEIR HATCHING





The Cigale confides its eggs to dry, slender twigs. All the branches

examined by Reaumur which bore such eggs were branches of the mulberry:

a proof that the person entrusted with the search for these eggs in the

neighbourhood of Avignon did not bring much variety to his quest. I find

these eggs not only on the mulberry-tree, but on the peach, the cherry,

the willow, the Japanese privet, and other trees. But these are

exceptions; what the Cigale really prefers is a slender twig of a

thickness varying from that of a straw to that of a pencil. It should

have a thin woody layer and plenty of pith. If these conditions are

fulfilled the species matters little. I should pass in review all the

semi-ligneous plants of the country were I to catalogue the various

supports which are utilised by the gravid female.



Its chosen twig never lies along the ground; it is always in a more or

less vertical position. It is usually growing in its natural position,

but is sometimes detached; in the latter case it will by chance have

fallen so that it retains its upright position. The insect prefers a

long, smooth, regular twig which can receive the whole of its eggs. The

best batches of eggs which I have found have been laid upon twigs of

the _Spartium junceum_, which are like straws stuffed with pith, and

especially on the upper twigs of the _Asphodelus cerasiferus_, which

rises nearly a yard from the ground before ramifying.



It is essential that the support, no matter what its nature, should be

dead and perfectly dry.



The first operation performed by the Cigale consists in making a series

of slight lacerations, such as one might make with the point of a pin,

which, if plunged obliquely downwards into the twig, would tear the

woody fibres and would compress them so as to form a slight

protuberance.



If the twig is irregular in shape, or if several Cigales have been

working successively at the same point, the distribution of the

punctures is confused; the eye wanders, incapable of recognising the

order of their succession or the work of the individual. One

characteristic is always present, namely, the oblique direction of the

woody fragment which is raised by the perforation, showing that the

Cigale always works in an upright position and plunges its rostrum

downwards in the direction of the twig.



If the twig is regular, smooth, and conveniently long the perforations

are almost equidistant and lie very nearly in a straight line. Their

number varies; it is small when the mother, disturbed in her operations,

has flown away to continue her work elsewhere; but they number thirty or

forty, more or less, when they contain the whole of her eggs.



Each one of the perforations is the entrance to an oblique tunnel, which

is bored in the medullary sheath of the twig. The aperture is not

closed, except by the bunch of woody fibres, which, parted at the moment

when the eggs are laid, recover themselves when the double saw of the

oviduct is removed. Sometimes, but by no means always, you may see

between the fibres a tiny glistening patch like a touch of dried white

of egg. This is only an insignificant trace of some albuminous secretion

accompanying the egg or facilitating the work of the double saw of the

oviduct.



Immediately below the aperture of the perforation is the egg chamber: a

short, tunnel-shaped cavity which occupies almost the whole distance

between one opening and that lying below it. Sometimes the separating

partition is lacking, and the various chambers run into one another, so

that the eggs, although introduced by the various apertures, are

arranged in an uninterrupted row. This arrangement, however, is not the

most usual.



The contents of the chambers vary greatly. I find in each from six to

fifteen eggs. The average is ten. The total number of chambers varying

from thirty to forty, it follows that the Cigale lays from three to four

hundred eggs. Reaumur arrived at the same figures from an examination of

the ovaries.



This is truly a fine family, capable by sheer force of numbers of

surviving the most serious dangers. I do not see that the adult Cigale

is exposed to greater dangers than any other insect: its eye is

vigilant, its departure sudden, and its flight rapid; and it inhabits

heights at which the prowling brigands of the turf are not to be feared.

The sparrow, it is true, will greedily devour it. From time to time he

will deliberately and meditatively descend upon the plane-trees from the

neighbouring roof and snatch up the singer, who squeaks despairingly. A

few blows of the beak and the Cigale is cut into quarters, delicious

morsels for the nestlings. But how often does the bird return without

his prey! The Cigale, foreseeing his attack, empties its intestine in

the eyes of its assailant and flies away.



But the Cigale has a far more terrible enemy than the sparrow. This is

the green grasshopper. It is late, and the Cigales are silent. Drowsy

with light and heat, they have exhausted themselves in producing their

symphonies all day long. Night has come, and with it repose; but a

repose frequently troubled. In the thick foliage of the plane-trees

there is a sudden sound like a cry of anguish, short and strident. It is

the despairing lamentation of the Cigale surprised in the silence by the

grasshopper, that ardent hunter of the night, which leaps upon the

Cigale, seizes it by the flank, tears it open, and devours the contents

of the stomach. After the orgy of music comes night and assassination.



I obtained an insight into this tragedy in the following manner: I was

walking up and down before my door at daybreak when something fell from

the neighbouring plane-tree uttering shrill squeaks. I ran to see what

it was. I found a green grasshopper eviscerating a struggling Cigale. In

vain did the latter squeak and gesticulate; the other never loosed its

hold, but plunged its head into the entrails of the victim and removed

them by little mouthfuls.



This was instructive. The attack was delivered high up above my head, in

the early morning, while the Cigale was resting; and the struggles of

the unfortunate creature as it was dissected alive had resulted in the

fall of assailant and assailed together. Since then I have often been

the witness of similar assassinations.



I have even seen the grasshopper, full of audacity, launch itself in

pursuit of the Cigale, who fled in terror. So the sparrow-hawk pursues

the skylark in the open sky. But the bird of prey is less ferocious than

the insect; it pursues a creature smaller than itself. The locust, on

the contrary, assails a colossus, far larger and far more vigorous than

its enemy; yet the result is a foregone conclusion, in spite of this

disproportion. With its powerful mandibles, like pincers of steel, the

grasshopper rarely fails to eviscerate its captive, which, being

weaponless, can only shriek and struggle.



The Cigale is an easy prey during its hours of somnolence. Every Cigale

encountered by the ferocious grasshopper on its nocturnal round must

miserably perish. Thus are explained those sudden squeaks of anguish

which are sometimes heard in the boughs during the hours of the night

and early morning, although the cymbals have long been silent. The

sea-green bandit has fallen upon some slumbering Cigale. When I wished

to rear some green grasshoppers I had not far to seek for the diet of my

pensioners; I fed them on Cigales, of which enormous numbers were

consumed in my breeding-cages. It is therefore an established fact that

the green grasshopper, the false Cigale of the North, will eagerly

devour the true Cigale, the inhabitant of the Midi.



But it is neither the sparrow nor the green grasshopper that has forced

the Cigale to produce such a vast number of offspring. The real danger

is elsewhere, as we shall see. The risk is enormous at the moment of

hatching and also when the egg is laid.



Two or three weeks after its escape from the earth--that is, about the

middle of July--the Cigale begins to lay. In order to observe the

process without trusting too much to chance, I took certain precautions

which would, I felt sure, prove successful. The dry Asphodelus is the

support preferred by the insect, as previous observations had assured

me. It was also the plant which best lent itself to my experiments, on

account of its long, smooth stems. Now, during the first years of my

residence in the South I replaced the thistles in my paddock by other

native plants of a less stubborn and prickly species. Among the new

occupants was the asphodel. This was precisely what I needed for my

experiments. I left the dry stems of the preceding year in place, and

when the breeding season arrived I inspected them daily.



I had not long to wait. As early as July 15th I found as many Cigales as

I could wish on the stems of the asphodel, all in process of laying. The

gravid female is always solitary. Each mother has her twig to herself,

and is in no danger of being disturbed during the delicate operation of

laying. When the first occupant has departed another may take her place,

and so on indefinitely. There is abundance of room for all; but each

prefers to be alone as her turn arrives. There is, however, no

unpleasantness of any kind; everything passes most peacefully. If a

female Cigale finds a place which has been already taken she flies away

and seeks another twig directly she discovers her mistake.



The gravid female always retains an upright position at this time, as

indeed she does at other times. She is so absorbed in her task that she

may readily be watched, even through a magnifying glass. The ovipositor,

which is about four-tenths of an inch in length, is plunged obliquely

and up to the hilt into the twig. So perfect is the tool that the

operation is by no means troublesome. We see the Cigale tremble

slightly, dilating and contracting the extremity of the abdomen in

frequent palpitations. This is all that can be seen. The boring

instrument, consisting of a double saw, alternately rises and sinks in

the rind of the twig with a gentle, almost imperceptible movement.

Nothing in particular occurs during the process of laying the eggs. The

insect is motionless, and hardly ten minutes elapse between the first

cut of the ovipositor and the filling of the egg-chamber with eggs.



The ovipositor is then withdrawn with methodical deliberation, in order

that it may not be strained or bent. The egg-chamber closes of its own

accord as the woody fibres which have been displaced return to their

position, and the Cigale climbs a little higher, moving upwards in a

straight line, by about the length of its ovipositor. It then makes

another puncture and a fresh chamber for another ten or twelve eggs. In

this way it scales the twig from bottom to top.



These facts being understood, we are able to explain the remarkable

arrangement of the eggs. The openings in the rind of the twig are

practically equidistant, since each time the Cigale moves upward it is

by a given length, namely, that of the ovipositor. Very rapid in flight,

she is a very idle walker. At the most you may see her, on the living

twig from which she is drinking, moving at a slow, almost solemn pace,

to gain a more sunny point close at hand. On the dry twig in which she

deposits her eggs she observes the same formal habits, and even

exaggerates them, in view of the importance of the operation. She moves

as little as possible, just so far as she must in order to avoid running

two adjacent egg-chambers into one. The extent of each movement upwards

is approximately determined by the depth of the perforation.



The apertures are arranged in a straight line when their number is not

very large. Why, indeed, should the insect wander to right or to left

upon a twig which presents the same surface all over? A lover of the

sun, she chooses that side of the twig which is most exposed to it. So

long as she feels the heat, her supreme joy, upon her back, she will

take good care not to change the position which she finds so delightful

for another in which the sun would fall upon her less directly.



The process of depositing the eggs is a lengthy one when it is carried

out entirely on the same twig. Counting ten minutes for each

egg-chamber, the full series of forty would represent a period of six or

seven hours. The sun will of course move through a considerable distance

before the Cigale can finish her work. In such cases the series of

apertures follows a spiral curve. The insect turns round the stalk as

the sun turns.



Very often as the Cigale is absorbed in her maternal task a diminutive

fly, also full of eggs, busily exterminates the Cigale's eggs as fast as

they are laid.



This insect was known to Reaumur. In nearly all the twigs examined he

found its grub, the cause of a misunderstanding at the beginning of his

researches. But he did not, could not see the audacious insect at work.

It is one of the Chalcididae, about one-fifth or one-sixth of an inch in

length; entirely black, with knotty antennae, which are slightly thicker

towards their extremities. The unsheathed ovipositor is implanted in the

under portion of the abdomen, about the middle, and at right angles to

the axis of the body, as in the case of the Leucospis, the pest of the

apiary. Not having taken the precaution to capture it, I do not know

what name the entomologists have bestowed upon it, or even if this dwarf

exterminator of the Cigale has as yet been catalogued. What I am

familiar with is its calm temerity, its impudent audacity in the

presence of the colossus who could crush it with a foot. I have seen as

many as three at once exploiting the unfortunate female. They keep close

behind the Cigale, working busily with their probes, or waiting until

their victim deposits her eggs.



The Cigale fills one of her egg-chambers and climbs a little higher in

order to bore another hole. One of the bandits runs to the abandoned

station, and there, almost under the claws of the giant, and without the

least nervousness, as if it were accomplishing some meritorious action,

it unsheathes its probe and thrusts it into the column of eggs, not by

the open aperture, which is bristling with broken fibres, but by a

lateral fissure. The probes works slowly, as the wood is almost intact.

The Cigale has time to fill the adjacent chamber.



As soon as she has finished one of these midges, the very same that has

been performing its task below her, replaces her and introduces its

disastrous egg. By the time the Cigale departs, her ovaries empty, the

majority of the egg-chambers have thus received the alien egg which will

work the destruction of their contents. A small, quick-hatching grub,

richly nourished on a dozen eggs, will replace the family of the Cigale.



The experience of centuries has taught the Cigale nothing. With her

excellent eyesight she must be able to perceive these terrible sappers

as they hover about her, meditating their crime. Too peaceable giantess!

if you see them why do you not seize them in your talons, crush the

pigmies at their work, so that you may proceed with your travail in

security? But no, you will leave them untouched; you cannot modify your

instincts, even to alleviate your maternal misfortunes.



The eggs of the common Cigale are of a shining ivory white. Conical at

the ends, and elongated in form, they might be compared in shape to the

weaver's shuttle. Their length is about one-tenth of an inch, their

diameter about one-fiftieth. They are packed in a row, slightly

overlapping one another. The eggs of the Cacan are slightly smaller, and

are assembled in regular groups which remind one of microscopical

bundles of cigars. We will consider the eggs of the common Cigale to the

exclusion of the others, as their history is the history of all.



September is not yet over when the shining white as of ivory gives way

to the yellow hue of cheese. During the first days of October you may

see, at the forward end of the egg, two tiny points of chestnut brown,

which are the eyes of the embryo in formation. These two shining eyes,

which almost seem to gaze at one, and the cone-shaped head of the egg,

give it the look of a tiny fish without fins--a fish for whom half a

nut-shell would make a capacious aquarium.



About the same time I notice frequently, on the asphodels in the paddock

and on those of the neighbouring hills, certain indications that the

eggs have recently hatched out. There are certain cast-off articles of

clothing, certain rags and tatters, left on the threshold of the

egg-chamber by the new-born grubs as they leave it and hurry in search

of a new lodging. We shall see in a moment what these vestiges mean.



But in spite of my visits, which were so assiduous as to deserve

success, I had never contrived to see the young Cigales emerge from

their egg-chambers. My domestic researches had been pursued in vain. Two

years running I had collected, in boxes, tubes, and bottles, a hundred

twigs of every kind which were peopled by the eggs of the Cigale; but

not one had shown me what I so desired to witness: the issue of the

new-born Cigales.



Reaumur experienced the same disappointment. He tells us how all the

eggs supplied by his friends were abortive, even when he placed them in

a glass tube thrust under his armpit, in order to keep them at a high

temperature. No, venerable master! neither the temperate shelter of our

studies and laboratories, nor the incubating warmth of our bodies is

sufficient here; we need the supreme stimulant, the kiss of the sun;

after the cool of the mornings, which are already sharp, the sudden

blaze of the superb autumn weather, the last endearments of summer.



It was under such circumstances, when a blazing sun followed a cold

night, that I found the signs of completed incubation; but I always came

too late; the young Cigales had departed. At most I sometimes found one

hanging by a thread to its natal stem and struggling in the air. I

supposed it to be caught in a thread of gossamer, or some shred of

cobweb.



At last, on the 27th of October, despairing of success, I gathered some

asphodels from the orchard, and the armful of dry twigs in which the

Cigales had laid their eggs was taken up to my study. Before giving up

all hope I proposed once more to examine the egg-chambers and their

contents. The morning was cold, and the first fire of the season had

been lit in my room. I placed my little bundle on a chair before the

fire, but without any intention of testing the effect of the heat of the

flames upon the concealed eggs. The twigs, which I was about to cut

open, one by one, were placed there to be within easy reach of my hand,

and for no other reason.



Then, while I was examining a split twig with my magnifying-glass, the

phenomenon which I had given up all hope of observing took place under

my eyes. My bundle of twigs was suddenly alive; scores and scores of the

young larvae were emerging from their egg-chambers. Their numbers were

such that my ambition as observer was amply satisfied. The eggs were

ripe, on the point of hatching, and the warmth of the fire, bright and

penetrating, had the effect of sunlight in the open. I was quick to

profit by the unexpected piece of good fortune.



At the orifice of the egg-chamber, among the torn fibres of the bark, a

little cone-shaped body is visible, with two black eye-spots; in

appearance it is precisely like the fore portion of the butter-coloured

egg; or, as I have said, like the fore portion of a tiny fish. You would

think that an egg had been somehow displaced, had been removed from the

bottom of the chamber to its aperture. An egg to move in this narrow

passage! a walking egg! No, that is impossible; eggs "do not do such

things!" This is some mistake. We will break open the twig, and the

mystery is unveiled. The actual eggs are where they always were, though

they are slightly disarranged. They are empty, reduced to the condition

of transparent skins, split wide open at the upper end. From them has

issued the singular organism whose most notable characteristics are as

follows:--



In its general form, the configuration of the head and the great black

eyes, the creature, still more than the egg, has the appearance of an

extremely minute fish. A simulacrum of a ventral fin increases the

resemblance. This apparent fin in reality consists of the two

fore-limbs, which, packed in a special sheath, are bent backwards,

stretched out against one another in a straight line. Its small degree

of mobility must enable the grub to escape from the egg-shell and, with

greater difficulty, from the woody tunnel leading to the open air.

Moving outwards a little from the body, and then moving back again, this

lever serves as a means of progression, its terminal hooks being already

fairly strong. The four other feet are still covered by the common

envelope, and are absolutely inert. It is the same with the antennae,

which can scarcely be seen through the magnifying-glass. The organism

which has issued from the egg is a boat-shaped body with a fin-shaped

limb pointing backwards on the ventral face, formed by the junction of

the two fore-limbs. The segmentation of the body is very clear,

especially on the abdomen. The whole body is perfectly smooth, without

the least suspicion of hair.



What name are we to give to this initial phase of the Cigale--a phase so

strange, so unforeseen, and hitherto unsuspected? Must I amalgamate some

more or less appropriate words of Greek and fabricate a portentous

nomenclature? No, for I feel sure that barbarous alien phrases are only

a hindrance to science. I will call it simply the _primary larva_, as I

have done in the case of the Meloides, the Leucospis, and the Anthrax.



The form of the primary larva of the Cigale is eminently adapted to its

conditions and facilitates its escape. The tunnel in which the egg is

hatched is very narrow, leaving only just room for passage. Moreover,

the eggs are arranged in a row, not end to end, but partially

overlapping. The larva escaping from the hinder ranks has to squeeze

past the empty shells, still in position, of the eggs which have already

hatched, so that the narrowness of the passage is increased by the empty

egg-shells. Under these conditions the larva as it will be presently,

when it has torn its temporary wrappings, would be unable to effect the

difficult passage. With the encumbrance of antennae, with long limbs

spreading far out from the axis of the body, with curved, pointed talons

which hook themselves into their medium of support, everything would

militate against a prompt liberation. The eggs in one chamber hatch

almost simultaneously. It is therefore essential that the first-born

larvae should hurry out of their shelter as quickly as possible, leaving

the passage free for those behind them. Hence the boat-like shape, the

smooth hairless body without projections, which easily squeezes its way

past obstructions. The primary larva, with its various appendages

closely wrapped against its body by a common sheath, with its fish-like

form and its single and only partially movable limb, is perfectly

adapted to make the difficult passage to the outer air.



This phase is of short duration. Here, for instance, a migrating larva

shows its head, with its big black eyes, and raises the broken fibres of

the entrance. It gradually works itself forward, but so slowly that the

magnifying-glass scarcely reveals its progress. At the end of half an

hour at the shortest we see the entire body of the creature; but the

orifice by which it is escaping still holds it by the hinder end of the

body.



Then, without further delay, the coat which it wears for this rough

piece of work begins to split, and the larva skins itself, coming out of

its wrappings head first. It is then the normal larva; the only form

known to Reaumur. The rejected coat forms a suspensory thread, expanding

at its free end to form a little cup. In this cup is inserted the end of

the abdomen of the larva, which, before allowing itself to fall to

earth, takes a sun-bath, grows harder, stretches itself, and tries its

strength, lightly swinging at the end of its life-line.



This little flea, as Reaumur calls it, first white, then amber-coloured,

is precisely the larva which will delve in the earth. The antennae, of

fair length, are free and waving to and fro; the limbs are bending at

their articulations; the fore-limbs, which are relatively powerful, open

and shut their talons. I can scarcely think of any more curious

spectacle than that of this tiny gymnast hanging by its tail, swinging

to the faintest breath, and preparing in the air for its entry into the

world. It hangs there for a variable period; some larvae let themselves

fall at the end of half an hour; others spend hours in their

long-stemmed cup; some even remain suspended until the following day.



Whether soon or late, the fall of the larva leaves suspended the thread

by which it hung, the wrappings of the primary larva. When all the brood

have disappeared, the aperture of the nest is thus hung with a branch of

fine, short threads, twisted and knotted together, like dried white of

egg. Each thread is expanded into a tiny cup at its free end. These are

very delicate and ephemeral relics, which perish at a touch. The least

wind quickly blows them away.



Let us return to the larva. Sooner or later, as we have seen, it falls

to the ground, either by accident or intention. The tiny creature, no

bigger than a flea, has preserved its tender newly-hatched flesh from

contact with the rough earth by hanging in the air until its tissues

have hardened. Now it plunges into the troubles of life.



I foresee a thousand dangers ahead. A mere breath of wind may carry this

atom away, and cast it on that inaccessible rock in the midst of a rut

in the road which still contains a little water; or on the sand, the

region of famine where nothing grows; or upon a soil of clay, too

tenacious to be tunnelled. These mortal accidents are frequent, for

gusts of wind are frequent in the windy and already severe weather of

the end of October.



This delicate organism requires a very soft soil, which can easily be

entered, so that it may immediately obtain a suitable shelter. The cold

days are coming; soon the frosts will be here. To wander on the surface

would expose it to grave perils. It must contrive without delay to

descend into the earth, and that to no trivial depth. This is the unique

and imperative condition of safety, and in many cases it is impossible

of realisation. What use are the claws of this tiny flea against rock,

sandstone, or hardened clay? The creature must perish if it cannot find

a subterranean refuge in good time.



Everything goes to show that the necessity of this first foothold on the

soil, subject as it is to so many accidents, is the cause of the great

mortality in the Cigale family. The little black parasite, the destroyer

of eggs, in itself evokes the necessity of a large batch of eggs; and

the difficulty which the larva experiences in effecting a safe lodgment

in the earth is yet another explanation of the fact that the maintenance

of the race at its proper strength requires a batch of three or four

hundred eggs from each mother. Subject to many accidents, the Cigale is

fertile to excess. By the prodigality of her ovaries she conjures the

host of perils which threaten her offspring.



During the rest of my experiment I can at least spare the larvae the

worst difficulties of their first establishment underground. I take some

soil from the heath, which is very soft and almost black, and I pass it

through a fine sieve. Its colour will enable me more easily to find the

tiny fair-skinned larvae when I wish to inform myself of passing events;

its lightness makes it a suitable refuge for such weak and fragile

beings. I pack it Pretty firmly in a glass vase; I plant in it a little

tuft of thyme; I sow in it a few grains of wheat. There is no hole at

the bottom of the vase, although there should be one for the benefit of

the thyme and the corn; but the captives would find it and escape by it.

The plantation and the crop will suffer from this lack of drainage, but

at least I am sure of recovering my larvae with the help of patience and

a magnifying-glass. Moreover, I shall go gently in the matter of

irrigation, giving only just enough water to save the plants from

perishing.



When all is in order, and when the wheat is beginning to shoot, I place

six young larvae of the Cigale on the surface of the soil. The tiny

creatures begin to pace hither and thither; they soon explore the

surface of their world, and some try vainly to climb the sides of the

vase. Not one of them seems inclined to bury itself; so that I ask

myself anxiously what can be the object of their prolonged and active

explorations. Two hours go by, but their wanderings continue.



What do they want? Food? I offer them some tiny bulbs with bundles of

sprouting roots, a few fragments of leaves and some fresh blades of

grass. Nothing tempts them; nothing brings them to a standstill.

Apparently they are seeking for a favourable point before descending

into the earth. But there is no need for this hesitating exploration on

the soil I have prepared for them; the whole area, or so it seems to me,

lends itself excellently to the operations which I am expecting to see

them commence. Yet apparently it will not answer the purpose.



Under natural conditions a little wandering might well be indispensable.

Spots as soft as my bed of earth from the roots of the briar-heather,

purged of all hard bodies and finely sifted, are rare in nature. Coarse

soils are more usual, on which the tiny creatures could make no

impression. The larva must wander at hazard, must make a pilgrimage of

indefinite duration before finding a favourable place. Very many, no

doubt, perish, exhausted by their fruitless search. A voyage of

exploration in a country a few inches wide evidently forms part of the

curriculum of young Cigales. In my glass prison, so luxuriously

furnished, this pilgrimage is useless. Never mind: it must be

accomplished according to the consecrated rites.



At last my wanderers grow less excited. I see them attack the earth with

the curved talons of their fore-limbs, digging their claws into it and

making such an excavation as the point of a thick needle would enter.

With a magnifying-glass I watch their picks at work. I see their talons

raking atom after atom of earth to the surface. In a few minutes there

is a little gaping well. The larva climbs downwards and buries itself,

henceforth invisible.



On the morrow I turn out the contents of the vase without breaking the

mould, which is held together by the roots of the thyme and the wheat. I

find all my larvae at the bottom, arrested by the glass. In twenty-four

hours they had sunk themselves through the entire thickness of the

earth--a matter of some four inches. But for obstacle at the bottom they

would have sunk even further.



On the way they have probably encountered the rootlets of my little

plantation. Did they halt in order to take a little nourishment by

implanting their proboscis? This is hardly probable, for a few rootlets

were pressed against the bottom of the glass, but none of my prisoners

were feeding. Perhaps the shock of reversing the pot detached them.



It is obvious that underground there is no other nourishment for them

than the sap of roots. Adult or larva, the Cigale is a strict

vegetarian. As an adult insect it drinks the sap of twigs and branches;

as a larva it sucks the sap of roots. But at what stage does it take the

first sip? That I do not know as yet, but the foregoing experiment seems

to show that the newly hatched larva is in greater haste to burrow deep

into the soil, so as to obtain shelter from the coming winter, than to

station itself at the roots encountered in its passage downwards.



I replace the mass of soil in the vase, and the six exhumed larvae are

once more placed on the surface of the soil. This time they commence to

dig at once, and have soon disappeared. Finally the vase is placed in my

study window, where it will be subject to the influences, good and ill,

of the outer air.



A month later, at the end of November, I pay the young Cigales a second

visit. They are crouching, isolated at the bottom of the mould. They do

not adhere to the roots; they have not grown; their appearance has not

altered. Such as they were at the beginning of the experiment, such they

are now, but rather less active. Does not this lack of growth during

November, the mildest month of winter, prove that no nourishment is

taken until the spring?



The young Sitares, which are also very minute, directly they issue from

the egg at the entrance of the tubes of the Anthrophorus, remain

motionless, assembled in a heap, and pass the whole of the winter in a

state of complete abstinence. The young Cigales apparently behave in a

very similar fashion. Once they have burrowed to such depths as will

safeguard them from the frosts they sleep in solitude in their winter

quarters, and await the return of spring before piercing some

neighbouring root and taking their first repast.



I have tried unsuccessfully to confirm these deductions by observation.

In April I unpotted my plant of thyme for the third time. I broke up the

mould and spread it under the magnifying-glass. It was like looking for

needles in a haystack; but at last I recovered my little Cigales. They

were dead, perhaps of cold, in spite of the bell-glass with which I had

covered the pot, or perhaps of starvation, if the thyme was not a

suitable food-plant. I give up the problem as too difficult of solution.



To rear such larvae successfully one would require a deep, extensive bed

of earth which would shelter them from the winter cold; and, as I do not

know what roots they prefer, a varied vegetation, so that the little

creatures could choose according to their taste. These conditions are by

no means impracticable, but how, in the large earthy mass, containing at

least a cubic yard of soil, should we recover the atoms I had so much

trouble to find in a handful of black soil from the heath? Moreover,

such a laborious search would certainly detach the larva from its root.



The early subterranean life of the Cigale escapes us. That of the

maturer larva is no better known. Nothing is more common, while digging

in the fields to any depth, to find these impetuous excavators under the

spade; but to surprise them fixed upon the roots which incontestably

nourish them is quite another matter. The disturbance of the soil warns

the larva of danger. It withdraws its proboscis in order to retreat

along its galleries, and when the spade uncovers it has ceased to feed.



If the hazards of field-work, with its inevitable disturbance of the

larvae, cannot teach us anything of their subterranean habits, we can at

least learn something of the duration of the larval stage. Some obliging

farmers, who were making some deep excavations in March, were good

enough to collect for me all the larvae, large and small, unearthed in

the course of their labour. The total collection amounted to several

hundreds. They were divided, by very clearly marked differences of size,

into three categories: the large larvae, with rudiments of wings, such as

those larvae caught upon leaving the earth possess; the medium-sized, and

the small. Each of these stages must correspond to a different age. To

these we may add the larvae produced by the last hatching of eggs,

creatures too minute to be noticed by my rustic helpers, and we obtain

four years as the probable term of the larvae underground.



The length of their aerial existence is more easily computed. I hear the

first Cigales about the summer solstice. A month later the orchestra has

attained its full power. A very few late singers execute their feeble

solos until the middle of September. This is the end of the concert. As

all the larvae do not issue from the ground at the same time, it is

evident that the singers of September are not contemporary with those

that began to sing at the solstice. Taking the average between these two

dates, we get five weeks as the probable duration of the Cigales' life

on earth.



Four years of hard labour underground, and a month of feasting in the

sun; such is the life of the Cigale. Do not let us again reproach the

adult insect with his triumphant delirium. For four years, in the

darkness he has worn a dirty parchment overall; for four years he has

mined the soil with his talons, and now the mud-stained sapper is

suddenly clad in the finest raiment, and provided with wings that rival

the bird's; moreover, he is drunken with heat and flooded with light,

the supreme terrestrial joy. His cymbals will never suffice to celebrate

such felicity, so well earned although so ephemeral.





THE CIGALE LEAVES ITS BURROW THE CLOTHO SPIDER facebooktwittergoogle_plusredditpinterestlinkedinmail

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