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CHAPTER XV
LOCUSTS

 

I
THEIR VALUE

“Mind you’re ready, children, to-morrow morning before the sun gets too hot. We’re going Locust-hunting.”

This announcement throws the household into great excitement at bed-time. What do my little helpers see in their dreams? Blue wings, red wings, suddenly flung out like fans; long saw-toothed legs, pale blue or pink, which kick out when we hold their owners in our fingers; great shanks that act like springs, and make the insect leap forward as though shot from a catapult.

If there be one peaceful and safe form of hunting, one in which both old age and childhood can share, it is Locust-hunting. What delicious mornings we owe to it! How delightful, when the mulberries are ripe, to pick them from the bushes! What excursions we have had, on the slopes covered with thin, tough grass, burnt yellow by the sun! I have vivid memories of such mornings, and my children will have them too.  

Little Paul has nimble legs, a ready hand, and a piercing eye. He inspects the clumps of everlastings, and peers closely into the bushes. Suddenly a big Grey Locust flies out like a little bird. The hunter first makes off at full speed, then stops and gazes in wonder at this mock Swallow flying far away. He will have better luck another time. We shall not go home without a few of those magnificent prizes.

Marie Pauline, who is younger than her brother, watches patiently for the Italian Locust, with his pink wings and carmine hind-legs; but she really prefers another, the most ornamented of them all. Her favourite wears a St. Andrew’s cross on the small of his back, which is marked by four white, slanting stripes. He wears, too, patches of green, the colour of verdigris on bronze. With her hand raised in the air, ready to swoop down, she approaches very softly, stooping low. Whoosh! That’s done it! The treasure is quickly thrust head-first into a paper funnel, and plunges with one bound to the bottom of it.

One by one our boxes are filled. Before the heat becomes too great to bear we are in possession of a number of specimens. Imprisoned in my cages, perhaps they will teach us something. In any case the Locusts have given pleasure to three people at a small cost.

Locusts have a bad reputation, I know. The textbooks describe them as noxious. I take the liberty of   doubting whether they deserve this reproach, except, of course, in the case of the terrible ravagers who are the scourge of Africa and the East. Their ill repute has been fastened on all Locusts, though they are, I consider, more useful than harmful. As far as I know, our peasants have never complained of them. What damage do they do?

They nibble the tops of the tough grasses which the Sheep refuses to touch; they prefer the thin, poor grass to the fat pastures; they browse on barren land that can support none but them; they live on food that no stomach but theirs could use.

Besides, by the time they frequent the fields the green wheat—the only thing that might tempt them—has long ago yielded its grain and disappeared. If they happen to get into the kitchen-gardens and take a few bites, it is not a crime. A man can console himself for a piece bitten out of a leaf or two of salad.

To measure the importance of things by one’s own turnip-patch is a horrible method. The short-sighted man would upset the order of the universe rather than sacrifice a dozen plums. If he thinks of the insect at all, it is only to kill it.

And yet, think what the consequences would be if all the Locusts were killed. In September and October the Turkeys are driven into the stubble, under charge of a child armed with two long reeds. The expanse over   which the gobbling flock slowly spreads is bare, dry, and burnt by the sun. At the most, a few ragged thistles raise their heads. What do the birds do in this famine-stricken desert? They cram themselves, that they may do honour to the Christmas table; they wax fat; their flesh becomes firm and good to eat. And pray, what do they cram themselves with? With Locusts. They snap them up, one here one there, till their greedy crops are filled with the delicious stuffing, which costs nothing, though its rich flavour will greatly improve the Christmas Turkey.

When the Guinea-fowl roams about the farm, uttering her rasping cry, what is it she seeks? Seeds, no doubt; but above all Locusts, which puff her out under the wings with a pad of fat, and give a better flavour to her flesh. The Hen, too, much to our advantage, is just as fond of them. She well knows the virtues of that dainty dish, which acts as a tonic and makes her lay more eggs. When left at liberty she rarely fails to lead her family to the stubble-fields, so that they may learn to snap up the nice mouthful skilfully. In fact, every bird in the poultry-yard finds the Locust a valuable addition to his bill of fare.

It is still more important outside the poultry-yard. Any who is a sportsman, and knows the value of the Red-legged Patridge, the glory of our southern hills, should open the crop of the bird he has just shot. He will find   it, nine times out of ten, more or less crammed with Locusts. The Partridge dotes on them, preferring them to seeds as long as he can catch them. This highly-flavoured, nourishing fare would almost make him forget the existence of seeds, if it were only there all the year round.

The Wheat-ear, too, who is so good to eat, prefers the Locust to any other food. And all the little birds of passage which, when autumn comes, call a halt in Provence before their great pilgrimage, fatten themselves with Locusts as a preparation for the journey.

Nor does man himself scorn them. An Arab author tells us:

“Grasshoppers”—(he means Locusts)—“are of good nourishment for men and Camels. Their claws, wings, and head are taken away, and they are eaten fresh or dried, either roast or boiled, and served with flesh, flour, and herbs.

”… Camels eat them greedily, and are given them dried or roast, heaped in a hollow between two layers of charcoal. Thus also do the Nubians eat them.…

“Once, when the Caliph Omar was asked if it were lawful to eat Grasshoppers, he made answer:

” ’Would that I had a basket of them to eat.’

“Wherefore, from this testimony, it is very sure that, by the Grace of God, Grasshoppers were given to man for his nourishment.”  

Without going as far as the Arab I feel prepared to say that the Locust is a gift of God to a multitude of birds. Reptiles also hold him in esteem. I have found him in the stomach of the Eyed Lizard, and have often caught the little Grey Lizard of the walls in the act of carrying him off.

Even the fish revel in him, when good fortune brings him to them. The Locust leaps blindly, and without definite aim: he comes down wherever he is shot by the springs in his legs. If the place where he falls happens to be water, a fish gobbles him up at once. Anglers sometimes bait their hooks with a specially attractive Locust.

As for his being fit nourishment for man, except in the form of Partridge and young Turkey, I am a little doubtful. Omar, the mighty Caliph who destroyed the library of Alexandria, wished for a basket of Locusts, it is true, but his digestion was evidently better than his brains. Long before his day St. John the Baptist lived in the desert on Locusts and wild honey; but in his case they were not eaten because they were good.

Wild honey from the pots of the Mason-bees is very agreeable food, I know. Wishing to taste the Locust also I once caught some, and had them cooked as the Arab author advised. We all of us, big and little, tried the queer dish at dinner. It was much nicer than the Cicadæ praised by Aristotle. I would go to the length of saying   it is good—without, however, feeling any desire for more.

 

II
THEIR MUSICAL TALENT

The Locust possesses musical powers wherewith to express his joys. Consider him at rest, blissfully digesting his meal and enjoying the sunshine. With sharp strokes of the bow, three or four times repeated with a pause between, he plays his tune. He scrapes his sides with his great hind-legs, using now one, now the other, and now both at a time.

The result is very poor, so slight indeed that I am obliged to make use of little Paul’s sharp ear to make sure that there is a sound at all. Such as it is, it is like the squeaking of a needle-point pushed across a sheet of paper. There you have the whole song, which is very nearly silence.

We can expect no more than this from the Locust’s very unfinished instrument. There is nothing here like the Cricket’s toothed bow and sounding-board. The lower edge of the wing-cases is rubbed by the thighs, but though both wing-cases and thighs are powerful they have no roughnesses to supply friction, and there is no sign of teeth.

This artless attempt at a musical instrument can produce   no more sound than a dry membrane will emit when you rub it yourself. And for the sake of this small result the insect lifts and lowers its thigh in sharp jerks, and appears perfectly satisfied. It rubs its sides very much as we rub our hands together in sign of contentment, with no intention of making a sound. That is its own particular way of expressing its joy in life.

Observe the Locust when the sky is partly covered with clouds, and the sun shines only at times. There comes a rift in the clouds. At once the thighs begin to scrape, becoming more and more active as the sun grows hotter. The strains are brief, but they are repeated as long as the sunshine continues. The sky becomes overcast. Then and there the song ceases; but is renewed with the next gleam of sunlight, always in brief outburst. There is no mistaking it: here, in these fond lovers of the light, we have a mere expression of happiness. The Locust has his moments of gaiety when his crop is full and the sun is kind.

Not all the Locusts indulge in this joyous rubbing.

The Tryxalis, who has a pair of immensely long hind-legs, keeps up a gloomy silence when even the sunshine is brightest. I have never seen him move his shanks like a bow; he seems unable to use them—so long are they—for anything but hopping.

The big Grey Locust, who often visits me in the enclosure, even in the depth of winter, is also dumb in   consequence of the excessive length of his legs. But he has a peculiar way of diverting himself. In calm weather, when the sun is hot, I surprise him in the rosemary bushes with his wings unfurled and fluttering rapidly, as though for flight. He keeps up this performance for a quarter of an hour at a time. His fluttering is so gentle, in spite of its extreme speed, that it creates hardly any rustling sound.

Others are still worse off. One of these is the Pedestrian Locust, who strolls on foot on the ridges of the Ventoux amid sheets of Alpine flowers, silvery, white, and rosy. His colouring is as fresh as that of the flowers. The sunlight, which is clearer on those heights than it is below, has made him a costume combining beauty with simplicity. His body is pale brown above and yellow below, his big thighs are coral red, his hind-legs a glorious azure-blue, with an ivory anklet in front. But in spite of being such a dandy he wears too short a coat.

His wing-cases are merely wrinkled slips, and his wings no more than stumps. He is hardly covered as far as the waist. Any one seeing him for the first time takes him for a larva, but he is indeed the full-grown insect, and he will wear this incomplete garment to the end.

With this skimpy jacket of course, music is impossible to him. The big thighs are there; but there are no wing-cases, no grating edge for the bow to rub upon.   The other Locusts cannot be described as noisy, but this one is absolutely dumb. In vain have the most delicate ears listened with all their might. This silent one must have other means of expressing his joys. What they are I do not know.

Nor do I know why the insect remains without wings, a plodding wayfarer, when his near kinsmen on the same Alpine slopes have excellent means of flying. He possesses the beginnings of wings and wing-cases, gifts inherited by the larva; but he does not develop these beginnings and make use of them. He persists in hopping, with no further ambition: he is satisfied to go on foot, to remain a Pedestrian Locust, when he might, one would think, acquire wings. To flit rapidly from crest to crest, over valleys deep in snow, to fly from one pasture to another, would certainly be great advantages to him. His fellow-dwellers on the mountain-tops possess wings and are all the better for them. It would be very profitable to extract from their sheaths the sails he keeps packed away in useless stumps; and he does not do it. Why?

No one knows why. Anatomy has these puzzles, these surprises, these sudden leaps, which defy our curiosity. In the presence of such profound problems the best thing is to bow in all humility, and pass on.  

 

III
THEIR EARLY DAYS

The Locust mother is not, in all cases, a model of affection. The Italian Locust, having laboriously half-buried herself in the sand, lays her eggs there and immediately bounds away. She gives not a look at the eggs, nor makes the least attempt to cover the hole where they lie. It closes of its own accord, as best it can, by the natural falling-in of the sand. It is an extremely casual performance, marked by an utter absence of maternal care.

Others do not forsake their eggs so recklessly. The ordinary Locust with the blue-and-black wings, for instance, after leaving her eggs in the sand, lifts her hind-legs high, sweeps some sand into the hole, and presses it down by stamping it rapidly. It is a pretty sight to watch the swift action of her slender legs, giving alternate kicks to the opening they are plugging. With this lively trampling the entrance to the home is closed and hidden away. The hole that contains the eggs completely disappears, so that no ill-intentioned creature could find it by sight alone.

Nor is this all. The power that works the two rammers lies in the hinder thighs, which, as they rise and   fall, scrape lightly against the edge of the wing-cases. This scraping produces a faint sound, similar to that with which the insect placidly lulls itself to sleep in the sun.

The Hen salutes with a song of gladness the egg she just laid; she announces her performance to the whole neighbourhood. The Locust celebrates the same event with her thin scraper. “I have buried underground,” she says, “the treasure of the future.”

img11.jpg
ITALIAN LOCUSTS

“I have buried underground,” she says, “the treasure of the future”

Having made the nest safe she leaves the spot, refreshes herself after her exertions with a few mouthfuls of green stuff, and prepares to begin again.

The Grey Locust mother is armed at the tip of her body—and so are other female Locusts in varying degrees—with four short tools, arranged in pairs and shaped like a hooked fingernail. On the upper pair, which are larger than the others, these hooks are turned upwards; on the lower and smaller pair they are turned downwards. They form a sort of claw, and are scooped out slightly, like a spoon. These are the pick-axes, the boring-tools with which the Grey Locust works. With these she bites into the soil, lifting the dry earth a little, as quietly as if she were digging in soft mould. She might be working in butter; and yet what the bore digs into is hard, unyielding earth.

The best site for laying the eggs is not always found at the first attempt. I have seen the mother make five   wells one after the other before finding a suitable place. When at last the business is over, and the insect begins to rise from the hole in which she is partly buried, one can see that she is covering her eggs with milk-white foam, similar to that of the Mantis.

This foamy matter often forms a button at the entrance to the well, a knot which stands up and attracts the eye by its whiteness against the grey background of the soil. It is soft and sticky, but hardens pretty soon. When this closing button is finished the mother moves away and troubles no more about her eggs, of which she lays a fresh batch elsewhere after a few days.

Sometimes the foamy paste does not reach the surface; it stops some way down, and before long is covered with the sand that slips from the edge. But in the case of my Locusts in captivity I always know, even when it is concealed, exactly where the barrel of eggs lies. Its structure is always the same, though there are variations in detail. It is always a sheath of solidified foam. Inside, there is nothing but foam and eggs. The eggs all lie in the lower portion, packed one on top of another; and the upper part consists only of soft, yielding foam. This portion plays an important part when the young larvæ are hatched. I will call it the ascending-shaft.

The wonderful egg-casket of the Mantis is not the result of any special talent which the mother can exercise   at will. It is due to mechanism. It happens of itself. In the same way the Locusts have no industry of their own, especially devised for laying eggs in a keg of froth. The foam is produced with the eggs, and the arrangement of eggs at the bottom and centre, and froth on the outside and the top, is purely mechanical.

There are many Locusts whose egg-cases have to last through the winter, since they do not open until the fine weather returns. Though the soil is loose and dusty at first, it becomes caked together by the winter rains. Supposing that the hatching takes place a couple of inches below the surface, how is this crust, this hard ceiling, to be broken? How is the larva to come up from below? The mother’s unconscious art has arranged for that.

The young Locust finds above him, when he comes out of the egg, not rough sand and hardened earth, but a straight tunnel, with solid walls that keep all difficulties away. This ascending-shaft is full of foam, which the larva can easily penetrate, and which will bring him quite close to the surface. Here only a finger’s-breadth of serious work remains to be done.

The greater part of the journey, therefore, is accomplished without effort. Though the Locust’s building is done quite mechanically, without the least intelligence, it is certainly singularly well devised.  

The little creature has now to complete his deliverance. On leaving his shell he is of a whitish colour, clouded with light red. His progress is made by worm-like movements; and, so that it may be as easy as possible, he is hatched, like the young Grasshopper, in a temporary jacket which keeps his antennæ and legs closely fixed to his body. Like the White-faced Decticus he keeps his boring-tool at his neck. Here there is a kind of tumour that swells and subsides alternately, and strikes the obstacle before it as regularly as a piston. When I see this soft bladder trying to overcome the hardness of the earth I come to the unhappy creature’s aid, and damp the layer of soil.

Even then the work is terribly hard. How it must labour, the poor little thing, how it must persevere with its throbbing head and writhing loins, before it can clear a passage for itself! The wee mite’s efforts show us plainly that the journey to the light of day is an enormous undertaking, in which the greater number would die but for the help of the exit-tunnel, the mother’s work.

When the tiny insect reaches the surface at last, it rests for a moment to recover from all that fatigue. Then suddenly the blister swells and throbs, and the temporary jacket splits. The rags are pushed back by the hind-legs, which are the last to be stripped. The   thing is done: the creature is free, pale in colouring as yet, but possessing its final form as a larva.

Immediately the hind-legs, hitherto stretched in a straight line, fall into the correct position. The legs fold under the great thighs, and the spring is ready to work. It works, Little Locust makes his entrance into the world, and hops for the first time. I offer him a bit of lettuce the size of my fingernail. He refuses it. Before taking nourishment he must first mature and grow in the sun.

 

IV
THEIR FINAL CHANGE

I have just beheld a stirring sight: the last change of a Locust, the full-grown insect emerging from his larval skin. It is magnificent. The object of my enthusiasm is the Grey Locust, the giant who is so common on the vines at vintage-time, in September. On account of his size—he is as long as my finger—he is easier to observe than any other of his tribe. The event took place in one of my cages.

The fat, ungraceful larva, a rough sketch of the perfect insect, is usually pale green; but some are blue-green, dirty yellow, red-brown, or even ashen-grey, like the grey of the full-grown Locust. The hind-legs, which are as powerful as those of mature age, have a   great haunch striped with red and a long shank shaped like a two-edged saw.

The wing-cases are at present two skimpy, triangular pinions, of which the free ends stand up like pointed gables. These two coat-tails, of which the material seems to have been clipped short with ridiculous meanness, just cover the creature’s nakedness at the small of the back, and shelter two lean strips, the germs of the wings. In brief, the sumptuous slender sails of the near future are at present sheer rags, of such meagre size as to be grotesque. From these miserable envelopes there will come a marvel of stately elegance.

The first thing to be done is to burst the old tunic. All along the corselet of the insect there is a line that is weaker than the rest of the skin. Waves of blood can be seen throbbing within, rising and falling alternately, distending the skin until at last it splits at the line of least resistance, and opens as though the two symmetrical halves had been soldered. The split is continued some little way back, and runs between the fastenings of the wings: it goes up the head as far as the base of the antennæ, where it sends a short branch to right and left.

Through this break the back is seen, quite soft, pale, hardly tinged with grey. Slowly it swells into a larger and larger hunch. At last it is wholly released. The head follows, pulled out of its mask, which remains   in its place, intact in the smallest particular, but looking strange with its great eyes that do not see. The sheaths of the antennæ, without a wrinkle, with nothing out of order, and with their usual position unchanged, hang over this dead face, which is now half transparent.

This means that the antennæ within, although fitted into narrow sheaths that enclose them as precisely as gloves, are able to withdraw without disturbing the covers in the smallest degree, or even wrinkling them. The contents manage to slip out as easily as a smooth, straight object could slip from a loose sheath. This mechanism is even more remarkable in the case of the hind-legs.

Now it is the turn of the fore-legs and intermediary legs to shed their armlets and gauntlets, always without the least rent, however small, without a crease of rumpled material, or a trace of any change in the natural position. The insect is now fixed to the top of the cage only by the claws of the long hind-legs. It hangs perpendicularly by four tiny hooks, head downwards, and it swings like a pendulum if I touch the wire-gauze.

The wing-cases and wings now emerge. These are four narrow strips, faintly grooved and looking like bits of paper ribbon. At this stage they are scarcely a quarter of their final length. They are so limp that they bend under their own weight and sprawl along the insect’s sides in the wrong direction, with their points towards the head   of the Locust. Imagine four blades of thick grass, bent and battered by a rain-storm, and you will have a fair picture of the pitiable bunch formed by the future wings.

The hind-legs are next released. The great thighs appear, tinted on their inner surface with pale pink, which will soon turn into a streak of bright crimson. They come out of the sheath quite easily, for the thick haunch makes way for the tapering knuckle.

The shank is a different matter. The shank of the full-grown insect bristles throughout its length with a double row of hard, pointed spikes. Moreover, the lower extremity ends in four large spurs. It is a genuine saw, but with two parallel sets of teeth.

Now this awkwardly shaped skin is enclosed in a sheath that is formed in exactly the same way. Each spur is fitted into a similar spur, each tooth into the hollow of a similar tooth. And the sheath is as close and as thin as a coat of varnish.

Nevertheless the saw-like skin slips out of its long narrow case without catching in it at any point whatever. If I had not seen this happen over and over again I could never have believed it. The saw does no injury to the dainty scabbard which a puff of my breath is enough to tear; the formidable rake slips through without leaving the least scratch behind it.

One would expect that, because of the spiked armour, the envelope of the leg would strip off in scales coming   loose of themselves, or would be rubbed off like dead skin. But the reality exceeds all possible expectation. From the spurs and spikes of the infinitely thin envelope there are drawn spurs and spikes so strong that they can cut soft wood. This is done without violence, the discarded skin remains where it was, hanging by the claws to the top of the cage, uncreased and untorn. The magnifying-glass shows not a trace of rough usage.

If it were suggested that one should draw out a saw from some sort of gold-beater’s skin sheath which had been exactly moulded on the steel, and that one should perform the operation without making the least tear, one would simply laugh. The thing would be impossible. Yet Nature makes light of such impossibilities; she can realise the absurd, in case of need.

The difficulty is overcome in this way. While the leg is being liberated it is not rigid, as it will presently be. It is soft and highly flexible. Where it is exposed to view I see it bending and curving: it is as supple as elastic cord. And farther on, where it is hidden, it is certainly still softer, it is almost fluid. The teeth of the saw are there, but have none of their future sharpness. The spikes lie backwards when the leg is about to be drawn back: as it emerges they stand up and become solid. A few minutes later the leg has attained the proper state of stiffness.

And now the fine tunic is wrinkled and rumpled, and   pushed back along the body towards the tip. Except at this point the Locust is bare. After a rest of twenty minutes he makes a supreme effort; he raises himself as he hangs, and grabs hold of his cast skin. Then he climbs higher, and fixes himself to the wire of the cage with his four front feet. He loosens the empty husk with one last shake, and it falls to the ground. The Locust’s transformation is conducted in much the same way as the Cicada’s.

The insect is now standing erect, and therefore the flexible wings are in the right position. They are no longer curved backwards like the petals of a flower, they are no longer upside down; but they still look shabby and insignificant. All that we see is a few wrinkles, a few winding furrows, which tell us that the stumps are bundles of cunningly folded material, arranged so as to take up as little space as possible.

Very gradually they expand, so gradually that their unfolding cannot be seen even under the microscope. The process continues for three hours. Then the wings and wing-cases stand up on the Locust’s back like a huge set of sails, sometimes colourless, sometimes pale-green, like the Cicada’s wings at the beginning. One is amazed at their size when one thinks of the paltry bundles that represented them at first. How could so much stuff find room there?

The fairy tale tells us of a grain of hempseed that   contained the under-linen of a princess. Here is a grain that is even more astonishing. The one in the story took years and years to sprout and multiply, till at last it yielded the hemp required for the trousseau: the Locust’s tiny bundle supplies a sumptuous set of sails in three hours. They are formed of exquisitely fine gauze, a network of innumerable tiny bars.

In the wing of the larva we can see only a few uncertain outlines of the future lace-work. There is nothing to suggest the marvellous fabric whose every mesh will have its form and place arranged for it, with absolute exactness. Yet it is there, as the oak is inside the acorn.

There must be something to make the matter of the wing shape itself into a sheet of gauze, into a labyrinth of meshes. There must be an original plan, an ideal pattern which gives each atom its proper place. The stones of our buildings are arranged in accordance with the architect’s plan; they form an imaginary building before they exist as a real one. In the same way a Locust’s wing, that sumptuous piece of lace emerging from a miserable sheath, speaks to us of another Architect, the Author of the plans which Nature must follow in her labours.