TWO STRANGE GRASSHOPPERS
I
THE EMPUSA
The sea, where life first appeared, still preserves in its depths many
of those curious shapes which were the earliest specimens of the animal
kingdom. But the land has almost entirely lost the strange forms of
other days. The few that remain are mostly insects. One of these is the
Praying Mantis, whose remarkable shape and habits I have already
described to you. Another is the Empusa.
This insect, in its undeveloped or larval state, is certainly the
strangest creature in all Provence: a slim, swaying thing of so
fantastic an appearance that unaccustomed fingers dare not lay hold of
it. The children of my neighbourhood are so much impressed by its
startling shape that they call it “the Devilkin.” They imagine it to be
in some way connected with witchcraft. One comes across it, though
never in great numbers, in the spring up to May; in autumn; and
sometimes in winter if the sun be strong. The tough grasses of the
waste-lands, the stunted bushes which catch the sunshine and are
sheltered from the wind by a few heaps of stones, are the chilly
Empusa’s favourite dwelling.
I will tell you, as well as I can, what she looks like. The tail-end of
her body is always twisted and curved up over her back so as to form a
crook, and the lower surface of her body (that is to say, of course,
the upper surface of the crook) is covered with pointed, leaf-shaped
scales, arranged in three rows. The crook is propped on four long, thin
legs, like stilts; and on each of these legs, at the point where the
thigh joins the shin, is a curved, projecting blade not unlike that of
a cleaver.
In front of this crook on stilts, this four-legged stool, there rises
suddenly—very long and almost perpendicular—the stiff corselet or bust.
It is round and slender as a straw, and at the end of it is the
hunting-trap, copied from that of the Mantis. This consists of a
harpoon sharper than a needle, and a cruel vice with jaws toothed like
a saw. The jaw, or blade formed by the upper arm, is hollowed into a
groove and carries five long spikes on each side, with smaller
indentations in between. The jaw formed by the fore-arm is grooved in
the same way, but the teeth are finer, closer, and more regular. When
at rest, the saw of the fore-arm fits into the groove of the upper arm.
If the machine were only larger it would be a fearful instrument of
torture.
The head is in keeping with this arsenal. What a queer head it is! A
pointed face, with curled moustaches; large goggle eyes; between them
the blade of a dirk; and on the forehead a mad, unheard-of thing—a sort
of tall mitre, an extravagant head-dress that juts forward, spreading
right and left into peaked wings. What does the Devilkin want with that
monstrous pointed cap, as magnificent as any ever worn by astrologer of
old? The use of it will appear presently.
The creature’s colouring at this time is commonplace—chiefly grey. As
it develops it becomes faintly striped with pale green, white, and
pink.
If you come across this fantastic object in the bramble-bushes, it
sways upon its four stilts, it wags its head at you knowingly, it
twists its mitre round and peers over its shoulder. You seem to see
mischief in its pointed face. But if you try to take hold of it this
threatening attitude disappears at once; the raised corselet is
lowered, and the creature makes off with mighty strides, helping itself
along with its weapons, with which it clutches the twigs. If you have a
practiced eye, however, the Empusa is easily caught, and penned in a
cage of wire-gauze.
At first I was uncertain how to feed them. My Devilkins were very
little, a month or two old at most. I gave them Locusts suited to their
size, the smallest I could find. They not only refused them, but were
afraid of them. Any thoughtless Locust that meekly approached an Empusa
met with a bad reception. The pointed mitre was lowered, and an angry
thrust sent the Locust rolling. The wizard’s cap, then, is a defensive
weapon. As the Ram charges with his forehead, so the Empusa butts with
her mitre.
I next offered her a live House-fly, and this time the dinner was
accepted at once. The moment the Fly came within reach the watchful
Devilkin turned her head, bent her corselet slantwise, harpooned the
Fly, and gripped it between her two saws. No Cat could pounce more
quickly on a Mouse.
To my surprise I found that the Fly was not only enough for a meal, but
enough for the whole day, and often for several days. These
fierce-looking insects are extremely abstemious. I was expecting them
to be ogres, and found them with the delicate appetites of invalids.
After a time even a Midge failed to tempt them, and through the winter
months they fasted altogether. When the spring came, however, they were
ready to indulge in a small piece of Cabbage Butterfly or Locust;
attacking their prey invariably in the neck, like the Mantis.
The young Empusa has one very curious habit when in captivity. In its
cage of wire-gauze its attitude is the same from first to last, and a
most strange attitude it is. It grips the wire by the claws of its four
hind-legs, and hangs motionless, back downwards, with the whole of its
body suspended from those four points. If it wishes to move, its
harpoons open in front, stretch out, grasp a mesh of the wire, and
pull. This process naturally draws the insect along the wire, still
upside down. Then the jaws close back against the chest.
And this upside-down position, which seems to us so trying, lasts for
no short while. It continues, in my cages, for ten months without a
break. The Fly on the ceiling, it is true, adopts the same position;
but she has her moments of rest. She flies, she walks in the usual way,
she spreads herself flat in the sun. The Empusa, on the other hand,
remains in her curious attitude for ten months on end, without a pause.
Hanging from the wire netting, back downwards, she hunts, eats,
digests, dozes, gets through all the experiences of an insect’s life,
and finally dies. She clambers up while she is still quite young; she
falls down in her old age, a corpse.
This custom is all the more remarkable in that it is practised only in
captivity. It is not an instinctive habit of the race; for out of doors
the insect, except at rare intervals, stands on the bushes back
upwards.
Strange as the performance is, I know of a similar case that is even
more peculiar: the attitude of certain Wasps and Bees during the
night’s rest. A particular Wasp, an Ammophila with red fore-legs, is
plentiful in my enclosure towards the end of August, and likes to sleep
in one of the lavender borders. At dusk, especially after a stifling
day when a storm is brewing, I am sure to find the strange sleeper
settled there. Never was a more eccentric attitude chosen for a night’s
rest. The jaws bite right into the lavender-stem. Its square shape
supplies a firmer hold than a round stalk would give. With this one and
only prop the Wasp’s body juts out stiffly at full length, with legs
folded. It forms a right angle with the stalk, so that the whole weight
of the insect rests upon the mandibles.
The Ammophila is enabled by its mighty jaws to sleep in this way,
extended in space. It takes an animal to think of a thing like that,
which upsets all our previous ideas of rest. Should the threatening
storm burst and the stalk sway in the wind, the sleeper is not troubled
by her swinging hammock; at most, she presses her fore-legs for a
moment against the tossing stem. Perhaps the Wasp’s jaws, like the
Bird’s toes, possess the power of gripping more tightly in proportion
to the violence of the wind. However that may be, there are several
kinds of Wasps and Bees who adopt this strange position,—gripping a
stalk with their mandibles, and sleeping with their bodies outstretched
and their legs folded back. This state of things makes us wonder what
it is that really constitutes rest.
About the middle of May the Empusa is transformed into her full-grown
condition. She is even more remarkable in figure and attire than the
Praying Mantis. She still keeps some of her youthful eccentricities—the
bust, the weapons on her knees, and the three rows of scales on the
lower surface of her body. But she is now no longer twisted into a
crook, and is comelier to look upon. Large pale-green wings, pink at
the shoulder and swift in flight, cover the white and green stripes
that ornament the body below. The male Empusa, who is a dandy, adorns
himself, like some of the Moths, with feathery antennæ.
When, in the spring, the peasant meets the Empusa, he thinks he sees
the common Praying Mantis, who is a daughter of the autumn. They are so
much alike that one would expect them to have the same habits. In fact,
any one might be tempted, led away by the extraordinary armour, to
suspect the Empusa of a mode of life even more atrocious than that of
the Mantis. This would be a mistake: for all their war-like aspect the
Empusæ are peaceful creatures.
Imprisoned in their wire-gauze bell-jar, either in groups of half a
dozen or in separate couples, they at no time lose their placidity.
Even in their full-grown state they are very small eaters, and content
themselves with a fly or two as their daily ration.
Big eaters are naturally quarrelsome. The Mantis, gorged with Locusts,
soon becomes irritated and shows fight. The Empusa, with her frugal
meals, is a lover of peace. She indulges in no quarrels with her
neighbours, nor does she pretend to be a ghost, with a view to
frightening them, after the manner of the Mantis. She never unfurls her
wings suddenly nor puffs like a startled Adder. She has never the least
inclination for the cannibal banquets at which a sister, after being
worsted in a fight, is eaten up. Nor does she, like the Mantis, devour
her husband. Such atrocities are here unknown.
The organs of the two insects are the same. These profound moral
differences, therefore, are not due to any difference in the bodily
form. Possibly they may arise from the difference in food. Simple
living, as a matter of fact, softens character, in animals as in men;
over-feeding brutalises it. The glutton, gorged with meat and strong
drink—a very common cause of savage outbursts—could never be as gentle
as the self-denying hermit who lives on bread dipped into a cup of
milk. The Mantis is a glutton: the Empusa lives the simple life.
And yet, even when this is granted, one is forced to ask a further
question. Why, when the two insects are almost exactly the same in
form, and might be expected to have the same needs, should the one have
an enormous appetite and the other such temperate ways? They tell us,
in their own fashion, what many insects have told us already: that
inclinations and habits do not depend entirely upon anatomy. High above
the laws that govern matter rise other laws that govern instincts.
II
THE WHITE-FACED DECTICUS
The White-faced Decticus stands at the head of the Grasshopper clan in
my district, both as a singer and as an insect of imposing presence. He
has a grey body, a pair of powerful mandibles, and a broad ivory face.
Without being plentiful, he is neither difficult nor wearisome to hunt.
In the height of summer we find him hopping in the long grass,
especially at the foot of the sunny rocks where the turpentine-tree
takes root.
The Greek word dectikos means biting, fond of biting. The Decticus is
well named. It is eminently an insect given to biting. Mind your finger
if this sturdy Grasshopper gets hold of it: he will rip it till the
blood comes. His powerful jaw, of which I have to beware when I handle
him, and the large muscles that swell out his cheeks, are evidently
intended for cutting up leathery prey.
I find, when the Decticus is imprisoned in my menagerie, that any fresh
meat tasting of Locust or Grasshopper suits his needs. The blue-winged
Locust is the most frequent victim. As soon as the food is introduced
into the cage there is an uproar, especially if the Dectici are hungry.
They stamp about, and dart forward clumsily, being hampered by their
long shanks. Some of the Locusts are caught at once, but others with
desperate bounds rush to the top of the cage, and there hang on out of
the reach of the Grasshopper, who is too stout to climb so high. But
they have only postponed their fate. Either because they are tired, or
because they are tempted by the green stuff below, they will come down,
and the Dectici will be after them immediately.
This Grasshopper, though his intellect is dull, possesses the art of
scientific killing of which we have seen instances elsewhere. He always
spears his prey in the neck, and, to make it helpless as quickly as
possible, begins by biting the nerves that enable it to move. It is a
very wise method, for the Locust is hard to kill. Even when beheaded he
goes on hopping. I have seen some who, though half-eaten, kicked out so
desperately that they succeeded in escaping.
With his weakness for Locusts, and also for certain seeds that are
harmful to unripe corn, these Grasshoppers might be of some service to
agriculture if only there were more of them. But nowadays his
assistance in preserving the fruits of the earth is very feeble. His
chief interest in our eyes is the fact that he is a memorial of the
remotest times. He gives us a vague glimpse of habits now out of use.
It was thanks to the Decticus that I first learnt one or two things
about young Grasshoppers.
Instead of packing their eggs in casks of hardened foam, like the
Locust and the Mantis, or laying them in a twig like the Cicada,
Grasshoppers plant them like seeds in the earth.
The mother Decticus has a tool at the end of her body with which she
scrapes out a little hole in the soil. In this hole she lays a certain
number of eggs, then loosens the dust round the side of the hole and
rams it down with her tool, very much as we should pack the earth in a
hole with a stick. In this way she covers up the well, and then sweeps
and smooths the ground above it.
She then goes for a little walk in the neighbourhood, by way of
recreation. Soon she comes back to the place where she has already laid
her eggs, and, very near the original spot, which she recognises quite
well, begins the work afresh. If I watch her for an hour I see her go
through this whole performance, including the short stroll in the
neighbourhood, no less than five times. The points where she lays the
eggs are always very close together.
When everything is finished I examine the little pits. The eggs lie
singly, without any cell or sheath to protect them. There are about
sixty of them altogether, pale lilac-grey in colour, and shaped like a
shuttle.
When I began to observe the ways of the Decticus I was anxious to watch
the hatching, so at the end of August I gathered plenty of eggs, and
placed them in a small glass jar with a layer of sand. Without
suffering any apparent change they spent eight months there under
cover, sheltered from the frosts, the showers, and the overpowering
heat of the sun, which they would be obliged to endure out of doors.
When June came, the eggs in my jar showed no sign of being about to
hatch. They were just as I had gathered them nine months before,
neither wrinkled nor tarnished, but on the contrary wearing a most
healthy look. Yet in June young Dectici are often to be met in the
fields, and sometimes even those of larger growth. What was the reason
of this delay, I wondered.
Then an idea came to me. The eggs of the Grasshopper are planted like
seeds in the earth, where they are exposed, without any protection, to
snow and rain. Those in my jar had spent two-thirds of the year in a
state of comparative dryness. Since they were sown like seeds, perhaps
they needed, to make them hatch, the moisture that seeds require to
make them sprout. I resolved to try.
I placed at the bottom of some glass tubes a pinch of backward eggs
taken from my collection, and on the top I heaped lightly a layer of
fine, damp sand. I closed the tubes with plugs of wet cotton, to keep
the air in them constantly moist. Any one seeing my preparations would
have supposed me to be a botanist experimenting with seeds.
My hopes were fulfilled. In the warmth and moisture the eggs soon
showed signs of hatching. They began to swell, and the bursting of the
shell was evidently close at hand. I spent a fortnight in keeping a
tedious watch at every hour of the day, for I had to surprise the young
Decticus actually leaving the egg, in order to solve a question that
had long been in my mind.
The question was this. The Grasshopper is buried, as a rule, about an
inch below the surface of the soil. Now the new-born Decticus, hopping
awkwardly in the grass at the approach of summer, has, like the
full-grown insect, a pair of very long tentacles, as slender as hairs;
while he carries behind him two extraordinary legs, two enormous hinged
jumping-poles that would be very inconvenient for ordinary walking. I
wished to find out how the feeble little creature set to work, with
this cumbrous luggage, to make its way to the surface of the earth. By
what means could it clear a passage through the rough soil? With its
feathery antennæ, which an atom of sand can break, and its immense
shanks, which are disjointed by the least effort, this mite is plainly
incapable of freeing itself.
As I have already told you, the Cicada and the Praying Mantis, when
issuing, the one from his twig, and the other from his nest, wear a
protective covering like an overall. It seemed to me that the little
Grasshopper, too, must come out through the sand in a simpler, more
compact form than he wears when he hops about the lawn on the day after
his birth.
Nor was I mistaken. The Decticus, like the others, wears an overall for
the occasion. The tiny, flesh-white creature is cased in a scabbard
which keeps the six legs flattened against the body, stretching
backwards, inert. In order to slip more easily through the soil his
shanks are tied up beside him; while the antennæ, those other
inconvenient appendages, are pressed motionless against the parcel.
The head is very much bent against the chest. With the big black specks
that are going to be its eyes, and its inexpressive, rather swollen
mask, it suggests a diver’s helmet. The neck opens wide at the back,
and, with a slow throbbing, by turns swells and sinks. It is by means
of this throbbing protrusion through the opening at the back of the
head that the new-born insect moves. When the lump is flat, the head
pushes back the damp sand a little way and slips into it by digging a
tiny pit. Then the swelling is blown out and becomes a knob which
sticks firmly in the hole. This supplies the resistance necessary for
the grub to draw up its back and push. Thus a step forward is made.
Each thrust of the motor-blister helps the little Decticus upon the
upward path.
It is pitiful to see this tender creature, still almost colourless,
knocking with its swollen neck and ramming the rough soil. With flesh
that is not yet hardened it is painfully fighting stone; and fighting
it so successfully that in the space of a morning it makes a gallery,
either straight or winding, an inch long and as wide as an average
straw. In this way the harassed insect reaches the surface.
Before it is altogether freed from the soil the struggler halts for a
moment, to recover from the effects of the journey. Then, with renewed
strength, it makes a last effort: it swells the protrusion at the back
of its head as far as it will go, and bursts the sheath that has
protected it so far. The creature throws off its overall.
Here, then, is the Decticus in his youthful shape, quite pale still,
but darker the next day, and a regular blackamoor compared with the
full-grown insect. As a prelude to the ivory face of his riper age he
wears a narrow white stripe under his hinder thighs.
Little Decticus, hatched before my eyes, life opens for you very
harshly! Many of your relatives must die of exhaustion before winning
their freedom. In my tubes I see numbers who, being stopped by a grain
of sand, give up the struggle half-way and become furred with a sort of
silky fluff. Mildew soon absorbs their poor little remains. And when
carried out without my help, their journey to the surface must be even
more dangerous, for the soil out of doors is coarse and baked by the
sun.
The little white-striped nigger nibbles at the lettuce-leaf I give him,
and leaps about gaily in the cage where I have housed him. I could
easily rear him, but he would not teach me much more. So I restore him
to liberty. In return for what he has taught me I give him the grass
and the Locusts in the garden.
For he taught me that Grasshoppers, in order to leave the ground where
the eggs are laid, wear a temporary form which keeps those too cumbrous
parts, the long legs and antennæ, swathed together in a sheath. He
taught me, too, that this mummy-like creature, fit only to lengthen and
shorten itself a little, has for its means of travelling a hernia in
the neck, a throbbing blister—an original piece of mechanism which,
when I first observed the Decticus, I had never seen used as an aid to
progression.