THE MANTIS: HER HATCHING
The eggs of the Praying Mantis usually hatch in bright sunshine, at
about ten o’clock on a mid-June morning. The median band or exit-zone
is the only portion of the nest that affords an outlet to the
youngsters.
From under each scale of that zone we see slowly appearing a blunt,
transparent protuberance, followed by two large black specks, which are
the eyes. Softly the new-born grub slips under the thin plate and
half-releases itself. Is it the little Mantis in his larval form, so
nearly allied to that of the adult? Not yet. It is a transition
organism. The head is opalescent, blunt, swollen, with palpitations
caused by the flow of the blood. The rest is tinted reddish-yellow. It
is quite easy to distinguish, under a general overall, the large black
eyes clouded by the veil that covers them, the mouth-parts flattened
against the chest, the legs plastered to the body from front to back.
Altogether, with the exception of the very obvious legs, the whole
thing, with its big blunt head, its eyes, its delicate abdominal
segmentation and its boatlike shape, reminds us somewhat of the first
state of the Cicadæ on leaving the egg, a state which is pictured
exactly by a tiny, finless fish.
Here then is a second instance of an organization of very brief
duration having as its function to bring into the light of day, through
narrow and difficult passes, a microscopic creature whose limbs, if
free, would, because of their length, be an insurmountable impediment.
To enable him to emerge from the exiguous tunnel of his twig, a tunnel
bristling with woody fibres and blocked with shells already empty, the
Cicada is born swathed in bands and endowed with a boat shape, which is
eminently suited to slipping easily through an awkward passage. The
young Mantis is exposed to similar difficulties. He has to emerge from
the depths of the nest through narrow, winding ways, in which
full-spread, slender limbs would not be able to find room. The high
stilts, the murderous harpoons, the delicate antennæ, organs which will
be most useful presently, in the brushwood, would now hinder the
emergence, would make it very laborious, impossible. The creature
therefore comes into existence swaddled and furthermore takes the shape
of a boat.
The case of the Cicada and the Mantis opens up a new vein to us in the
inexhaustible entomological mine. I extract from it a law which other
and similar facts, picked up more or less everywhere, will certainly
not fail to confirm. The true larva is not always the direct product of
the egg. When the newborn grub is likely to experience special
difficulties in effecting its deliverance, an accessory organism, which
I shall continue to call the primary larva, precedes the genuine larval
state and has as its function to bring to the light of day the tiny
creature which is incapable of releasing itself.
To go on with our story, the primary larvæ show themselves under the
thin plates of the exit-zone. A vigorous flow of humours occurs in the
head, swelling it out and converting it into a diaphanous and
ever-throbbing blister. In this way the splitting-apparatus is
prepared. At the same time, the little creature, half-caught under its
scale, sways, pushes forward, draws back. Each swaying is accompanied
by an increase of the swelling in the head. At last the prothorax
arches and the head is bent low towards the chest. The tunic bursts
across the prothorax. The little animal tugs, wriggles, sways, bends
and straightens itself again. The legs are drawn from their sheaths;
the antennæ, two long parallel threads, are likewise released. The
creature is now fastened to the nest only by a worn-out cord. A few
shakes complete the deliverance.
We here have the insect in its genuine larval form. All that remains
behind is a sort of irregular cord, a shapeless clout which the least
breath blows about like a flimsy bit of fluff. It is the exit-tunic
violently shed and reduced to a mere rag.
For all my watchfulness, I missed the moment of hatching in the case of
the Grey Mantis. The little that I know is reduced to this: at the end
of the spur or promontory with which the nest finishes in front is a
small, dull-white speck, formed of very powdery foam. This round pore
is only just plugged with a frothy stopper and constitutes the sole
outlet from the nest, which is thoroughly strengthened at every other
part. It takes the place of the long band of scales through which the
Praying Mantis is released. It is here that the youngsters must emerge
one by one from their casket. Chance does not favour me and I do not
witness the exodus, but, soon after the family has come forth, I see
dangling at the entrance to the liberating pore a shapeless bunch of
white cast-off clothes, thin skins which a puff of wind would disperse.
These are the garments flung aside by the young as they make their
appearance in the open air; and they testify to the presence of a
transition wrapper which permits of movement inside the maze of the
nest. The Grey Mantis therefore also has her primary larva, which packs
itself up in a narrow sheath, conducive to escape. The period of this
emergence is June.
To return to the Praying Mantis. The hatching does not take place all
over the nest at one time, but rather in sections, in successive swarms
which may be separated by intervals of two days or more. The pointed
end, containing the last eggs, usually begins. This inversion of
chronological order, calling the last to the light of day before the
first, may well be due to the shape of the nest. The thin end, which is
more accessible to the stimulus of a fine day, wakes up before the
blunt end, which is larger and does not so soon acquire the necessary
amount of heat.
Sometimes, however, although still broken up in swarms, the hatching
embraces the whole length of the exit-zone. A striking sight indeed is
the sudden exodus of a hundred young Mantes. Hardly does the tiny
creature show its black eyes under a scale before others appear
instantly, in their numbers. It is as though a certain shock were being
communicated from one to another, as though an awakening signal were
transmitted, so swiftly does the hatching spread all round. Almost in a
moment the median band is covered with young Mantes who run about
feverishly, stripping themselves of their rent garments.
The nimble little creatures do not stay long on the nest. They let
themselves drop off or else clamber into the nearest foliage. All is
over in less than twenty minutes. The common cradle resumes its
peaceful condition, prior to furnishing a new legion a few days later;
and so on until all the eggs are finished.
I have witnessed this exodus as often as I wished to, either out of
doors, in my enclosure, where I had deposited in sunny places the nests
gathered more or less everywhere during my winter leisure, or else in
the seclusion of a greenhouse, where I thought, in my simplicity, that
I should be better able to protect the budding family. I have witnessed
the hatching twenty times if I have once; and I have always beheld a
scene of unforgetable carnage. The round-bellied Mantis may procreate
germs by the thousands: she will never have enough to cope with the
devourers who are destined to decimate the breed from the moment that
it leaves the egg.
The Ants above all are zealous exterminators. Daily I surprise their
ill-omened visits on my rows of nests. It is vain for me to intervene,
however seriously; their assiduity never slackens. They seldom succeed
in making a breach in the fortress: that is too difficult; but, greedy
of the dainty flesh in course of formation inside, they await a
favourable opportunity, they lie in wait for the exit.
Despite my daily watchfulness, they are there the moment that the young
Mantes appear. They grab them by the abdomen, pull them out of their
sheaths, cut them up. You see a piteous fray between tender babes
gesticulating as their only means of defence and ferocious brigands
carrying their spolia opima at the end of their mandibles. In less than
no time the massacre of the innocents is consummated; and all that
remains of the flourishing family is a few scattered survivors who have
escaped by accident.
The future assassin, the scourge of the insect race, the terror of the
Locust on the brushwood, the dread devourer of fresh meat, is herself
devoured, from her birth, by one of the least of that race, the Ant.
The ogress, prolific to excess, sees her family thinned by the dwarf.
But the slaughter is not long continued. So soon as she has acquired a
little firmness from the air and strengthened her legs, the Mantis
ceases to be attacked. She trots about briskly among the Ants, who fall
back as she passes, no longer daring to tackle her. With her
grappling-legs brought close to her chest, like arms ready for
self-defence, already she strikes awe into them by her proud bearing.
A second connoisseur in tender meats pays no heed to these threats.
This is the little Grey Lizard, the lover of sunny walls. Apprised I
know not how of the quarry, here he comes, picking up one by one, with
the tip of his slender tongue, the stray insects that have escaped the
Ants. They make a small mouthful but an exquisite one, so it seems, to
judge by the blinking of the reptile’s eye. For each little wretch
gulped down, its lid half-closes, a sign of profound satisfaction. I
drive away the bold Lizard who ventures to perpetrate his raid before
my eyes. He comes back again and, this time, pays dearly for his
rashness. If I let him have his way, I should have nothing left.
Is this all? Not yet. Another ravager, the smallest of all but not the
least formidable, has anticipated the Lizard and the Ant. This is a
very tiny Hymenopteron armed with a probe, a Chalcis, who establishes
her eggs in the newly-built nest. The Mantis’ brood shares the fate of
the Cicada’s: parasitic vermin attack the eggs and empty the shells.
Out of all that I have collected I often obtain nothing or hardly
anything. The Chalcis has been that way.
Let us gather up what the various exterminators, known or unknown, have
left me. When newly hatched, the larva is of a pale hue, white faintly
tinged with yellow. The swelling of its head soon diminishes and
disappears. Its colour is not long in darkening and turns light-brown
within twenty-four hours. The little Mantis very nimbly lifts up her
grappling-legs, opens and closes them; she turns her head to right and
left; she curls her abdomen. The fully-developed larva has no greater
litheness and agility. For a few minutes the family stops where it is,
swarming over the nest; then it scatters at random on the ground and
the plants hard by.
I instal a few dozen emigrants under bell-covers. On what shall I feed
these future huntresses? On game, obviously. But what game? To these
miniature creatures I can only offer atoms. I serve them up a
rose-branch covered with Green Fly. The plump Aphis, a tender morsel
suited to my feeble guests, is utterly scorned. Not one of the captives
touches it.
I try them with Midges, the smallest that chance flings into my net as
it sweeps the grass, and meet with the same obstinate refusal. I offer
them pieces of Fly, hung here and there on the gauze of the cover. None
accepts my quarters of venison. Perhaps the Locust will tempt them, the
Locust on whom the adult Mantis dotes? A prolonged and minute search
places me in possession of what I want. This time the bill of fare will
consist of a few recently hatched Acridians. Young as they are, they
have already reached the size of my charges. Will the little Mantes
fancy these? They do not fancy them: at the sight of their tiny prey
they run away dismayed.
Then what do you want? What other game do you find on your native
brushwood? I can see nothing. Can you have some special infants’ food,
vegetarian perhaps? Let us even try the improbable. The very tenderest
bit of the heart of a lettuce is declined. So are the different sorts
of grass which I tax my ingenuity in varying; so are the drops of honey
which I place on spikes of lavender. All my endeavours come to nothing;
and my captives die of inanition.
My failure has its lessons. It seems to point to a transition diet
which I have not been able to discover. Long ago, the larvæ of the
Oil-beetles gave me a great deal of trouble, before I knew that they
want as their first food the egg of the Bee whose store of honey they
will afterwards consume. Perhaps the young Mantes also in the beginning
demand a special pap, something more in keeping with their frailty.
Despite its resolute air, I do not quite see the feeble little creature
hunting. The game, whatever it be, kicks out, when attacked, frisks
about, defends itself; and the assailant is not yet in a condition to
ward off even the flap of a Midge’s wing. Then what does it feed on? I
should not be surprised if there were interesting facts to be picked up
in this baby-food question.
These fastidious ones, so difficult to provide with nourishment, meet
with even more pitiful deaths than hunger. When only just born, they
fall a prey to the Ant, the Lizard and other ravagers who lie in wait,
patiently, for the exquisite provender to hatch. The egg itself is not
respected. An infinitesimal perforator inserts her own eggs in the nest
through the barrier of solidified foam, thus settling her offspring,
which, maturing earlier, nips the Mantis’ family in the bud. How many
are called and how few are chosen! There were a thousand of them
perhaps, sprung from one mother who was capable of giving birth to
three broods. One couple alone escapes extermination, one alone keeps
up the breed, seeing that the number remains more or less the same from
year to year.
Here a serious question arises. Can the Mantis have acquired her
present fecundity by degrees? Can she, as the ravages of the Ant and
others reduced her progeny, have increased the output of her ovaries so
as to make up for excessive destruction by excessive production? Could
the enormous brood of to-day be due to the wastage of former days? So
think some, who are ready, without convincing proofs, to see in animals
even more profound changes brought about by circumstances.
In front of my window, on the sloping margin of the pond, stands a
magnificent cherry-tree. It came there by accident, a sturdy wilding,
disregarded by my predecessors and to-day respected far more for its
spreading branches than for its fruit, which is of very indifferent
quality. In April it forms a splendid white-satin dome. Its blossoms
are as snow; their fallen petals carpet the ground. Soon the red
cherries appear in profusion. O my beautiful tree, how lavish you are
and what a number of baskets you will fill!
And for this reason what revelry up above! The Sparrow is the first to
hear of the ripe cherries and comes trooping, morning and evening, to
pilfer and squall; he informs his friends in the neighbourhood, the
Greenfinch and the Warbler, who hasten up and banquet for weeks on end.
Butterflies flit from one nibbled cherry to another, taking delicious
sips at each. Rose-chafers bite great mouthfuls out of the fruit, then
fall asleep sated. Wasps and Hornets burst open the sweet caskets; and
the Gnats follow to get drunk in their wake. A plump maggot, settled in
the very centre of the pulp, blissfully feasts upon its juicy
dwelling-house and waxes big and fat. It will rise from table to change
into a comely Fly.
On the ground there are others at the banquet. A host of footpads is
battening on the fallen cherries. At night, the Field-mice come
gathering the stones stripped by the Wood-lice, Earwigs, Ants and
Slugs; they hoard them in their burrows. During the long winter they
will make holes in them to extract and nibble the kernels. A numberless
throng lives upon the generous cherry-tree.
What would the tree require to provide a successor one day and maintain
its species in a state of harmonious and well-balanced prosperity? A
single seed would be enough; and every year it gives forth bushels and
bushels. Tell me why, please.
Shall we say that the cherry-tree, at first very economical with its
fruit, became lavish by degrees in order thus to escape its
multitudinous ravagers? Shall we say of the tree, as we said of the
Mantis, that excessive destruction gradually induced excessive
production? Who would dare to venture on such rash statements? Is it
not perfectly obvious that the cherry-tree is one of those factories in
which elements are wrought into organic matter, one of those
laboratories in which the dead thing is changed into the thing fitted
to live? No doubt, cherries ripen that they may be perpetuated; but
these are the minority, the very small minority. If all seeds were to
sprout and to develop fully, there would long ago have been no room on
the earth for the cherry-tree alone. The vast majority of its fruits
fulfil another function. They serve as food for a crowd of living
creatures, who are not skilled as the plant is in the transcendental
chemistry that turns the uneatable into the eatable.
Matter, in order to serve in the highest manifestations of life, must
undergo slow and most delicate elaboration. That elaboration begins in
the workshop of the infinitely small, of the microbe, for instance, one
of which, more powerful than the lightning’s might, combines oxygen and
nitrogen and produces nitrates, the primary food of plants. It begins
on the confines of nothingness, is improved in the vegetal, is yet
further refined in the animal and step by step attains the substance of
the brain.
How many hidden labourers, how many unknown manipulators worked perhaps
for centuries, first at getting the rough ore and then at the refining
of that grey matter which becomes the brain, the most marvellous of the
implements of the mind, even if it were capable only of making us say:
“Two and two are four!”
The rocket, when rising, reserves for the culminating point of its
ascent the dazzling fountain of its many-coloured lights. Then all is
dark again. Its smoke, its gases, its oxides will, in the long run, be
able to reconstitute other explosives by vegetable processes. Even so
does matter act in its metamorphoses. From stage to stage, from one
delicate refinement to another yet more delicate, it succeeds in
attaining heights where the splendours of the intellect shine forth
through its agency; then, shattered by the effort, it relapses into the
nameless thing whence it started, into scattered molecules which are
the common origin of living things.
At the head of the assemblers of organic matter stands the plant, the
animal’s senior. Directly or indirectly, it is to-day, as it was in the
geological period, the chief purveyor to beings more generously endowed
with life. In the laboratory of its cell the food of the universe at
least gets its first rough preparation. Comes the animal, which
corrects the preparation, improves it and transmits it to others of a
higher order. Cropped grass becomes mutton; and mutton becomes human
flesh or Wolf-flesh, according to the consumer.
Among those elaborators of nourishing atoms which do not create organic
matter out of any- and everything, starting with the mineral, as the
plant does, the most prolific are the fishes, the first-born of
vertebrate animals. Ask the Cod what she does with her millions of
eggs. Her answer will be that of the beech with its myriads of nuts, or
the oak with its myriads of acorns. She is immensely fruitful in order
to feed an immense number of the hungry. She is continuing the work
which her predecessors performed in remote ages, when nature, not as
yet rich in organic matter, hastened to increase her reserves of life
by bestowing prodigious exuberance upon her primeval workers.
The Mantis, like the fish, dates back to those distant epochs. Her
strange shape and her uncouth habits have told us so. The richness of
her ovaries confirms it. She retains in her entrails a feeble relic of
the procreative fury that prevailed in olden times under the dank shade
of the arborescent ferns; she contributes, in a very humble but none
the less real measure, to the sublime alchemy of living things.
Let us look closely at her work. The grass grows thick and green,
drawing its nourishment from the earth. The Locust crops it. The Mantis
makes a meal of the Locust and swells out with eggs, which are laid, in
three batches, to the number of a thousand. When they hatch, up comes
the Ant and levies an enormous tribute on the brood. We appear to be
retroceding. In vastness of bulk, yes; in refinement of instinct,
certainly not. In this respect how far superior is the Ant to the
Mantis! Besides, the cycle of possible happenings is not closed.
Young Ants still contained in their cocoon—popularly known as
Ants’-eggs—form the food on which the Pheasant’s brood is reared. These
are domestic poultry just as much as the Pullet and the Capon, but
their keep makes greater demands on the owner’s care and purse. When it
grows big, this poultry is let loose in the woods; and people calling
themselves civilized take the greatest pleasure in bringing down with
their guns the poor creatures which have lost the instinct of
self-preservation in the pheasantries, or, to speak plainly, in the
poultry-yard. You cut the throat of the Chicken required for roasting;
you shoot, with all the parade of sport, that other Chicken, the
Pheasant. I fail to understand those insensate massacres.
Tartarin of Tarascon, in the absence of game, used to shoot at his cap.
I prefer that. And above all I prefer the hunting, real hunting, of
another fervent consumer of Ants, the Wryneck, the Tiro-lengo of the
Provençaux, so-called because of his scientific method of darting his
immensely-long and sticky tongue across a procession of Ants and then
suddenly withdrawing it all black with the limed insects. With such
mouthfuls as these, the Wryneck becomes disgracefully fat in autumn; he
plasters himself with butter on his rump and sides and under his wings;
he hangs a string of it round his neck; he pads his skull with it right
down to the beak.
He is then delicious, roasted: small, I admit; no bigger than a Lark,
at the outside; but, small though he be, unlike anything else and
immeasurably superior to the Pheasant, who must begin to go bad before
developing a flavour at all.
Let me for this once do justice to the merit of the humblest! When the
table is cleared after the evening meal and all is quiet and my body
relieved for the time being of its physiological needs, sometimes I
succeed in picking up, here and there, a good idea or two; and it may
well be that the Mantis, the Locust, the Ant and even lesser creatures
contribute to these sudden gleams of light which flash unaccountably
into one’s mind. By strange and devious paths, they have all supplied,
in their respective ways, the drop of oil that feeds the lamp of
thought. Their energies, slowly developed, stored up and handed down by
predecessors, become infused into our veins and sustain our weakness.
We live by their death.
To conclude. The Mantis, prolific to excess, in her turn makes organic
matter, bequeathing it to the Ant, who bequeaths it to the Wryneck, who
bequeaths it perhaps to man. She procreates a thousand, partly to
perpetuate her species, but far more than she may contribute, according
to her means, to the general picnic of the living. She brings us back
to the ancient symbol of the Serpent biting its own tail. The world is
an endless circle: everything finishes so that everything may begin
again; everything dies so that everything may live.