THE SPANISH COPRIS: THE LAYING OF THE EGGS

If we show instinct doing for the egg what would be done on the advice of reason matured by study and experience, we achieve a result of no small philosophic importance; and an austere scientific conscience begins to trouble me with scruples. Not that I wish to give science a forbidding aspect: I am convinced that one can say the wisest things without employing a barbarous vocabulary. Clearness is the supreme courtesy of the wielder of the pen. I do my best to observe it. No, the scruple that stops me is of another kind.

I begin to wonder if I am not in this case the victim of an illusion. I say to myself:

‘Gymnopleuri and Sacred Beetles, when in the open air, are manufacturers of balls or pills. That is their trade, learnt we know not how, prescribed perhaps by their structure, in particular by their long legs, some of which are slightly curved. When they are making preparations for the egg, is it so wonderful that they continue underground their own ball-making speciality?’

If we leave out of the question the neck of the pear and the projecting tip of the ovoid, details much more difficult to explain, there remains the most important part so far [128]as bulk is concerned, the globular part, a repetition of the thing which the insect makes outside the burrow; there remains the pellet with which the Sacred Beetle plays in the sunshine, sometimes without making any other use of it, the ball which the Gymnopleurus rolls peacefully over the turf.

Then what is the object here of the globular form, the best preventative of desiccation during the heat of summer? This property of the sphere and of its near neighbour, the ovoid, is an accepted physical fact; but it is only by accident that these shapes are the right ones to overcome that difficulty. A creature built for rolling balls across the fields goes on making balls underground. If the grub fare all the better for finding tender foodstuffs under its mandibles to the very end, that is a capital thing for the grub, but it is no reason why we should extol the instinct of the mother.

So I argued, saying to myself that, before I was convinced, I should need to be shown a Dung-beetle who was utterly unfamiliar with the pill-making business in everyday life and who yet, when laying-time was at hand, made an abrupt change in her habits and shaped her provisions into a ball. My Dung-beetle would have to be a good fat one too. Is there any such in my neighbourhood? Yes, there is; and she is one of the handsomest and largest, next to the Sacred Beetle. I speak of the Spanish Copris (C. hispanus, Lin.), who is so remarkable on account of the sharp slope of her corselet and the disproportionate size of the horn surmounting her head.

Round and squat, the Spanish Copris with her ponderous gait is certainly a stranger to gymnastics such as are performed by the Sacred Beetle or the Gymnopleurus. Her legs, which are of insignificant length and folded [129]under her belly at the slightest alarm, bear no comparison with the stilts of the pill-rollers. Their stunted form and lack of flexibility are enough in themselves to tell us that their owner would not care to roam about hampered by a rolling ball.

The Copris is indeed of a sedentary habit. Once he has found his provisions, at night or in the evening twilight, he digs a burrow under the heap. It is a rough cavern, large enough to hold an apple. Here is introduced, bit by bit, the stuff that is just over his head or at any rate lying on the threshold of the cavern; here is engulfed, in no definite shape, an enormous supply of victuals, bearing eloquent witness to the insect’s gluttony. As long as the hoard lasts, the Copris, engrossed in the pleasures of the table, does not return to the surface. The home is not abandoned until the larder is emptied, when the insect recommences its nocturnal quest, finds a new treasure and scoops out another temporary dwelling.

As his trade is merely that of a gatherer of manure, shovelling in the stuff without any preliminary manipulation, the Copris is evidently quite ignorant, for the time being, of the art of kneading and modelling a globular loaf. Besides, his short, clumsy legs seem utterly irreconcilable with any such art.

In May, or June at latest, comes laying-time. The insect, so ready to fill its own belly with the most sordid materials, becomes particular where the portion of its family is concerned. Like the Sacred Beetle, like the Gymnopleurus, it now wants the soft produce of the Sheep, deposited in a single slab. Even when abundant, the cake is buried on the spot in its entirety. Not a trace of it remains outside. Economy demands that it be collected to the very last crumb.[130]

You see: no travelling, no carting, no preparations. The cake is carried down to the cellar by armfuls, at the very spot where it lies. The insect repeats, with an eye to its grubs, what it did when working for itself. As for the burrow, whose presence is indicated by a good-sized mound, it is a roomy cavern excavated to a depth of some eight inches. I observe that it is more spacious and better built than the temporary abodes occupied by the Copris at times of revelry.

But let us turn from the insect in its wild state to the insect in captivity. In the former case the evidence furnished by chance encounters would be incomplete, fragmentary and of dubious relevancy; and we shall do better to watch the Copris in my insect-house, especially as she lends herself admirably to this sort of observation. Let us observe the storing first.

In the soft evening light I see her appear on the threshold of her burrow. She has come up from the depths, she is going to gather in her harvest. She has not far to go: the provisions are there, outside the door, a generous supply which I am careful to replenish. Cautiously, ready to retreat at the least alarm, she makes her way to them with a slow and measured step. Her shield does the rummaging and dissecting, her fore-legs are busy extracting. An armful, quite a modest one, is pulled away, crumbling to pieces. The Copris drags it backwards and disappears underground. In less than two minutes, she is back again. With feathery antennæ outspread, she warily scans the neighbourhood before crossing the threshold of her dwelling.

A distance of two or three inches separates her from the heap of provisions. It is a serious matter for her to venture so far. She would have liked the victuals to be [131]exactly overhead, forming a roof to her house. That would have saved her from having to make these expeditions, which are a source of anxiety. I have decided otherwise. To facilitate observation, I have placed the supplies just on one side. By degrees the nervous creature is reassured; it becomes accustomed to the open air and to my presence, which, of course, I make as unobtrusive as possible. Armful after armful goes down into the cellar. They are always shapeless bits, shreds such as one might pick off with a small pair of pincers.

Having learnt what I want to know about the insect’s method of warehousing its provisions, I leave it to its work, which continues for the best part of the night. On the following days, nothing happens; the Copris goes out no more. Enough treasure has been laid up in a single night. Let us wait a while and leave her time to stow away her stuff as she pleases.

Before the week is out, I dig up the soil in my insect-house and bring to light the burrow whose victualling I have been watching. As in the fields, it is a spacious hall with an irregular, elliptic roof and an almost level floor. In a corner is a round hole, similar to the orifice in the neck of a bottle. This is the goods-entrance, opening on a slanting gallery that runs up to the surface of the soil. The walls of this house, which was hollowed out of fresh earth, have been carefully compressed and are strong enough to resist any seismic disturbances caused by my excavations. It is easy to see that the insect, toiling for the future, has put forth all its skill, all its digging-powers, in order to produce lasting work. The banqueting-tent may be a hole hurriedly scooped out, with irregular and none too stable walls, but the permanent dwelling is of larger dimensions and much more carefully built.[132]

I suspect that both sexes have a share in this architectural masterpiece; at least, I often come upon the pair in the burrows destined for the laying of the eggs. The roomy and luxurious apartment was no doubt once the wedding-hall; the marriage was consummated under the mighty dome in the building of which the lover had cooperated: a gallant way of declaring his passion. I also suspect him of lending his partner a hand with the collecting and storing of the provisions. From what I have gathered, he too, strong as he is, shares in this finicking work, collects his armfuls and descends into the crypt. It is a quicker job when there are two to help. But, once the home is well stocked, he retires discreetly, makes his way back to the surface and goes and settles down elsewhere, leaving the mother to her delicate task. His part in the family-mansion is ended.

Now what do we find in this mansion, to which we have seen so many tiny loads of provisions lowered? A mass of small pieces, heaped together anyhow? Not a bit of it. I always find a simple lump, a huge loaf which fills the dwelling except for a narrow passage all round, just wide enough to give the mother room to move.

This sumptuous portion, a regular Twelfth-Night cake, has no fixed shape. I come across some that are ovoid, suggesting a Turkey’s egg in form and size; I find some that are a flattened ellipsoid, similar to the common onion; I discover some that are almost round, reminding me of a Dutch cheese; I see some that are circular with a slight swelling on the upper surface, like the loaves of the Provençal peasant or, better still, the egg-cake, the fougasso à l’iôu with which he celebrates Easter. In every case the surface is smooth and nicely curved.[133]

There is no mistaking what has happened: the mother has collected and kneaded into one lump the numerous fragments brought down one after the other; out of all those particles she has made a homogeneous thing, by mashing them, working them together and treading on them. Time after time I come across the baker on top of the colossal loaf which makes the Sacred Beetle’s pill look so insignificant; she strolls about on the convex surface, which sometimes measures as much as four inches across; she pats the mass, makes it firm and level. I just catch sight of the curious scene, for, the moment she is perceived, the pastry-cook slips down the curved slope and hides away under her cake.

For a further knowledge of the work, for a study of its innermost detail, we shall have to resort to artifice. There is scarcely any difficulty about it. Either my long practice with the Sacred Beetle has made me more skilful in my methods of research, or else the Copris is less reserved and bears the rigours of captivity more philosophically: at any rate, I succeed, without the slightest trouble, in following all the phases of the nest-making to my heart’s content.

I employ two methods, each of them adapted for enlightening me on some special points. Whenever the vivarium supplies me with a few large cakes, I take these out of the burrows, together with the mother Copris, and place them in my study. The receptacles are of two sorts, according to whether I want light or darkness. In the former case, I use glass jars with a diameter more or less the same as that of the burrows, say four to five inches. At the bottom of each is a thin layer of fresh sand, quite insufficient to allow the Copris to bury herself in it, but still serving the purpose of sparing the insect the slippery [134]foothold of the actual glass and giving it the illusion of a soil similar to that of which I have just deprived it. With this layer the jar becomes a suitable cage for the mother and her loaf.

I need hardly say that the startled insect would not undertake anything while light prevailed, no matter how dim and tempered. It must have complete darkness, which I produce by means of a cardboard sheath enclosing the jar. By carefully raising this sheath a little, I can surprise the captive at her work whenever I feel inclined, the light in my study being a shaded one, and even watch operations for a time. The reader will notice that this arrangement is much less complex than that which I used when I wished to see the Sacred Beetle engaged in modelling her pear, the simpler method being made possible by the different temperament of the Copris, who is more easy-going than her kinswoman. A dozen of these eclipsed appliances are thus arranged on my large laboratory-table. Any one seeing them standing in a row would take them for a collection of groceries in whity-brown paper bags.

For my dark apparatus I use flower-pots filled with fresh, well-packed sand. The mother and her cake occupy the lower part, which is adapted as a niche by means of a cardboard screen forming a ceiling and supporting the sand above. Or else I simply put the mother on the surface of the sand with a supply of provisions. She digs herself a burrow, does her warehousing, makes herself a home; and things follow the usual course. In all cases I rely upon a sheet of glass, which does duty as a lid, to keep my prisoners safe. These different devices will, I trust, give me information on a delicate point of which I will say more later.[135]

What do the glass jars covered with an opaque sheath teach us? A good many things, all of them interesting, and this to begin with: the big loaf does not owe its curve—which is always regular, no matter how much the actual shape may vary—to any rolling process. Our inspection of the natural burrow has already told us that so large a mass could not have been rolled into a cavity of which it fills almost the whole space. Besides, the strength of the insect would be unequal to moving so great a load.

From time to time I go to the jar for information and on every occasion the same evidence is forthcoming. I see the mother, hoisted on top of the lump, feeling here, feeling there, bestowing little taps, smoothing away the projecting points, perfecting the thing; never do I catch her looking as though she wanted to turn the block. It is clear as daylight: rolling has nothing whatever to do with the matter.

The dough-maker’s assiduity, her patient care make me suspect an industrial detail whereof I was far from dreaming. Why so many after-touches to the mass, why so long a wait before making use of it? It is, in fact, a week or more before the insect, still busy with its pressing and polishing, makes up its mind to do something with its hoard.

When the baker has kneaded his dough to the requisite extent, he collects it into a single lump in a corner of the kneading-trough. The leaven will work better in the depths of the voluminous mass. The Copris knows this bakehouse secret. She heaps together all that she has collected in her foraging; she carefully kneads the whole into a provisional loaf and allows it time to improve by virtue of an internal process that gives flavour to the paste [136]and makes it of the right consistency for subsequent manipulations. As long as this chemical process remains unfinished, both the baker and the Copris wait. In the case of the insect, it goes on for some time, a week at least.

At last it is ready. The baker’s man divides his lump into smaller lumps, each of which will become a loaf. The Copris does the same thing. By means of a circular cut made with the sharp edge of her forehead and the saw of her fore-legs, she detaches from the mass a piece of the prescribed size. With this stroke there is no hesitation, no after-touches adding a bit here and taking off a bit there. Straight away and with one sharp, decisive cut, she obtains the proper-sized lump.

It now becomes a question of shaping it. Clasping it as best she can in her short arms, so little adapted, one would think, to work of this kind, the Copris rounds her lump of dough by means of pressure and of pressure only. Gravely she moves about on the still shapeless pill, climbs up, climbs down, turns to right and left, above and below; here she methodically applies a little more pressure, there a little less, touching and retouching with unvarying patience, and finally, after twenty-four hours of it, the piece that was all corners has become a perfect sphere, the size of a plum. There, in her crowded studio, with scarcely room to move, the podgy artist has completed her work without once shaking it on its base; by dint of time and patience she has obtained the geometrical sphere which her clumsy tools and her confined space seemed bound to deny her.

For a long time the insect continues to touch up its globe, polishing it affectionately, passing its foot gently to and fro until the least protuberance has disappeared. These meticulous finishing touches seem endless. Towards [137]the end of the second day, however, the sphere is pronounced satisfactory. The mother climbs to the dome of her edifice and there, still by simple pressure, hollows out a shallow crater. In this basin the egg is laid.

Then, with extreme caution, with a delicacy that is most surprising with such rough tools, the lips of the crater are brought together so as to form a vaulted roof over the egg. The mother turns slowly, does a little raking, draws the stuff upwards and finishes the closing-process. This is the most ticklish work of all. A little too much pressure, a miscalculated thrust might easily jeopardize the life of the germ under its thin ceiling.

Every now and then the mother suspends operations. Motionless, with lowered forehead, she seems to be sounding the cavity beneath, to be listening to what is happening inside. All’s well, it seems; and once again she resumes her patient toil: the careful, delicate scraping of the sides towards the summit, which begins to taper a little and lengthen out. In this way an ovoid with the small end uppermost takes the place of the original sphere. Under the more or less projecting nipple is the hatching-chamber with the egg. Twenty-four hours more are spent in this minute work. Total: four times round the clock and sometimes longer to construct the sphere, scoop out a basin, lay the egg and shut it in by transforming the sphere into an ovoid.

The insect goes back to the cut loaf and helps itself to a second slice, which, by the same manipulations as before, becomes an ovoid tenanted by an egg. The surplus suffices for a third ovoid, sometimes even for a fourth. I have never seen this number exceeded when the mother had at her disposal only the materials which she had accumulated in the burrow.[138]

The laying is over. Here is the mother in her retreat, which is almost filled by the three or four cradles standing one against the other, pointed end upwards. What will she do now? Go away, no doubt, to recruit her strength a little in the open air after her prolonged fast. He who thinks so is mistaken. She stays. And yet she has eaten nothing since she came underground, taking good care not to touch the loaf, which, divided into equal portions, will provide the sustenance of the family. The Copris is touchingly scrupulous where the children’s inheritance is concerned: she is a devoted mother, who braves hunger rather than let her offspring suffer privation.

She braves it for a second reason: to mount guard around the cradles. From the end of June onwards the burrows are difficult to find, because the mounds disappear through the action of storm or wind or the feet of the passers-by. The few which I succeed in discovering always contain the mother dozing beside a group of pills, in each of which a grub, now nearing its complete development, feasts on the fat of the land.

My dark appliances, flower-pots filled with fresh sand, confirm what the fields have taught me. Buried with provisions in the first fortnight in May, the mothers do not reappear on the surface, under the glass lid. They keep hidden in the burrow after laying their eggs; they spend the sultry dog-days with their ovoids, watching them, no doubt, as the glass-jars, with their freedom from subterranean obscurity, tell us.

They come up again at the time of the first autumnal rains in September. But by then the new generation has attained its perfect form. The mother, therefore, enjoys in her underground home that rare privilege for an insect, the joy of knowing her family; she hears her [139]children scratching at the shell to obtain their liberty; she is present at the bursting of the casket which she has fashioned so conscientiously; maybe she helps the exhausted weaklings when the ground has not been cool enough to soften the walls. Mother and progeny leave the underworld together; and together they arrive at the autumn banquets, when the sun is mild and the ovine manna abounds along the paths.

The flower-pots teach us something else. I place on the surface a few separate couples taken from their burrows at the outset of the building-operations. They are given a generous supply of provisions. Each couple buries itself, settles down and starts hoarding; then, after ten days or so, the male reappears on the surface, under the sheet of glass. The other does not stir an inch. The eggs are laid, the food-balls are shaped, patiently rounded and grouped at the bottom of the pot. And all the time, so that he may not disturb the mother in her work, the father remains exiled from the gynæceum. He has climbed to the surface with the intention of going and digging himself a shelter elsewhere. Being unable to do so within the narrow confines of the pot, he stays at the top, barely concealed from view by a modicum of sand or a few scraps of food. A lover of darkness and of the cool underground depths, he remains obstinately for three months exposed to the air and drought and light; he refuses to go to earth, lest he should interfere with the sacred things that are taking place below. The Copris shall have a good mark for thus respecting the maternal apartments.

Let us come back to the jars, where the events hidden from us by the soil are to be enacted before our eyes. The three or four pills, each with its egg, stand one against another and occupy almost the whole enclosure, leaving [140]only narrow passages. Of the original lump very little remains, at the most a few crumbs, which come in handy when appetite returns. But that does not worry the mother much. She is far more concerned about her ovoids.

Assiduously she goes from one to another, feels them, listens to them, touches them up at points where my eye can perceive no flaw. Her clumsy, horn-shod foot, more sensitive in darkness than my retina in broad daylight, is perhaps discovering incipient cracks or defective workmanship in the matter of consistency which must be attended to, in order to prevent the air from entering and drying up the eggs. The prudent mother therefore slips in and out of the narrow spaces between the cradles, inspecting them carefully and remedying any accident, no matter how trifling. If I disturb her, she sometimes rubs the tip of her abdomen against the edge of her wing-cases, producing a soft rustling noise, which is almost a murmur of complaint. Thus, between scrupulous care and brief slumbers beside her group of cradles, the mother passes the three months essential to the evolution of the family.

I seem to catch a glimpse of the reason for this long watch. The pill-rollers, whether Scarabs or Gymnopleuri, never have more than a single pear, a single ovoid in their burrows. The mass of foodstuff, which at times is rolled from a great distance, is necessarily limited by the insect’s own limitations of strength. It is enough for one larva, but not enough for two. An exception must be made with respect to the Broad-necked Scarab, who brings up her family very frugally and divides her rolling booty into two modest portions.

The others are obliged to dig a special burrow for each egg. When everything is in order in the new establishment—and this does not take long—they leave the underground [141]vault and go off somewhere else, wherever chance may lead them, to begin their pill-rolling, excavating and egg-laying once more. With these nomadic habits, any prolonged supervision on the mother’s part becomes impossible.

The Scarab suffers by it. Her pear, which is magnificently regular at the outset, soon shows cracks and becomes scaly and swollen. Various cryptogams invade it and undermine it; the material expands and the resultant splitting causes the pear to lose its shape. We have seen how the grub combats these troubles.

The Copris has other ways. She does not roll her stores from a distance; she warehouses them on the spot, bit by bit, which enables her to accumulate in a single burrow enough to satisfy all her brood. As there is no need for further expeditions, the mother stays and keeps watch. Under her never-failing vigilance, the pill does not crack, for any crevice is stopped up as soon as it appears; nor does it become covered with parasitic vegetation, for nothing can grow on a soil that is constantly being raked. The two or three dozen ovoids which I have before my eyes all bear witness to the mother’s watchfulness: not one of them is split or cracked or infested with tiny fungi. In all of them the surface is irreproachable. But, if I take them away from the mother to put them into a bottle or tin, they suffer the same fate as the Sacred Beetle’s pears: in the absence of supervision, destruction more or less complete overtakes them.

Two examples will be instructive to us here. I take from a mother two or three pills and place them in a tin, which prevents them from getting dry. Before a week has passed, they are covered with a fungous vegetation. More or less everything grows in this fertile soil; the lesser fungi delight in it. To-day it is an infinitesimal [142]crystalline plant swollen into a bobbin-shape, bristling with short, dew-beaded hairs and ending in a little round head as black as jet. I have not the leisure to consult books and microscope and give a name to the tiny apparition which attracts my attention for the first time. This botanical detail is of little importance: all that we need know is that the dark green of the pills has disappeared under the thick white crystalline growth stippled with black specks.

I restore the two pills to the Copris keeping watch over her third. I replace the opaque sheath and leave the insect undisturbed in the dark. In an hour’s time or less, I look to see how things are getting on. The parasitic vegetation has entirely disappeared, cut down, extirpated to the last stalk. The magnifying-glass fails to reveal a trace of what, a little while before, was a dense thicket. The insect has used its rake, those notched legs, to some purpose; and the surface of the pill is once more in the unblemished condition necessary for health.

The other experiment is a more serious one. With the point of my penknife I make a gash in a pill at the upper end and lay bare the egg. Here we have an artificial breach not unlike those which might be caused naturally, but of much greater size. I give back to the mother the violated cradle, threatened with disaster unless she intervenes. But she does intervene and that quickly, once darkness comes. The ragged edges slit by the penknife are brought together and soldered. The small amount of stuff lost is replaced by scrapings taken from the sides. In a very short time the breach is so neatly repaired that not a trace remains of my onslaught.

I repeat it, making the danger graver and attacking all four pills with my desecrating penknife, which cuts right [143]through the hatching-chamber and leaves the egg only an incomplete shelter under the gaping roof. The mother’s counter-move is swift and effective. In one brief spell of work everything is put right again. Yes, I can quite believe that with this vigilant supervisor, who never sleeps except with one eye open, there is no possibility of the cracks and the puffiness which so often disfigure the Sacred Beetle’s pear.

Four pills containing eggs are all that I have been able to obtain from the big loaf which I took from the burrow at the time of the nuptials. Does this mean that the Copris can lay only that number? I think so. I even believe that usually there are less, three, two, or possibly only one. My boarders, installed in separate potfuls of sand at nesting-time, did not reappear on the surface once they had stored away the necessary provisions; they never came out to dip into the replenished stock and enable themselves to increase the always restricted number of ovoids lying at the bottom of the pot under the mother’s watchful care.

This limitation of the family might very well be due partly to lack of space. Three or four pills completely fill the burrow; there is no room for more; and the mother, a stay-at-home alike from duty and inclination, does not dream of digging another dwelling. It is true that greater breadth in the one which she has would solve the problem of room; but then a ceiling of excessive length would be liable to collapse. Suppose I were myself to intervene, suppose I provided space without the risk of the roof falling in, could there be an increase in the number of eggs?

Yes, the number is almost doubled. My trick is quite simple. In one of the glass jars, I take away her three or four pills from a mother who has just finished the last. [144]None of the loaf remains. I substitute for it one of my own making, kneaded with the tip of a paper-knife. A new type of baker, I do over again very nearly what the insect did at the beginning. Reader, do not smile at my baking: science shall give it the odour of sanctity.

My cake is favourably received by the Copris, who sets to work again, starts laying anew and presents me with three of her perfect ovoids, making seven in all, the greatest number that I obtained in my various attempts of this kind. A large piece of the bun remains available. The Copris does not utilize it, at least not for nest-building; she eats it. The ovaries appear to be exhausted. This much is proved: the pillaging of the burrow provides space; and the mother, taking advantage of it, nearly doubles the number of her eggs with the aid of the cake which I make for her.

Under natural conditions nothing of a similar kind can happen. There is no obliging baker at hand, to shape and pat a new cake and slip it into the oven that is the Copris’ cellar. Everything therefore tells us that the stay-at-home Beetle, who makes up her mind not to reappear until the cool autumn days, is of very limited bearing-capacity. Her family consists of three or four at most. Occasionally, in the dog-days, long after laying-time is past, I have even dug up a mother watching over a solitary pill. This one, perhaps for lack of provisions, had reduced her maternal joys to the narrowest limits.

The loaves kneaded with my paper-knife are readily accepted. We will take advantage of this fact to make a few experiments. Instead of the big, substantial cake, I fashion a pill which is a replica in shape and size of the three or four which the mother is guarding after confiding the egg to them. My imitation is a fairly good one. If [145]I were to mix up the two products, the natural and the artificial, I might easily fail to distinguish between them afterwards. The counterfeit pill is placed in the jar, beside the other. The disturbed insect at once hides in a corner, under a little sand. I leave it in peace for a couple of days. Then how great is my surprise to find the mother on the top of my pill, digging a cup into it! In the afternoon the egg is laid and the cup closed. I can only tell my pill from those of the Copris by the place which it occupies. I had put it at the extreme right of the group, and at the extreme right I find it, duly operated on by the insect. How could the Beetle know that this ovoid, so like the others in every respect, was untenanted? How did she allow herself unhesitatingly to scoop the top into a crater when, judging by appearances, there might be an egg just underneath? She takes good care not to do any fresh excavating on the finished pills. What guide leads her to the artificial one, which is extremely deceptive in appearance, and bids her dig into that?

I do it again and yet again. The result is the same: the mother does not confuse her work with mine and takes advantage of the presence of my pill to install an egg in it. On only one occasion, when her appetite seems suddenly to have come back, did I see her feeding on my loaf. But her discrimination between the tenanted and the untenanted was just as clearly marked here as in the previous instance. Instead of attacking, in her hunger, the pills with eggs, by what miracle of divination does she turn, in spite of their exact outward similarity, to the pill which contains nothing?

Can my handiwork be defective? Did the wooden blade not press hard enough to impart the proper consistency? Is there something wrong with the dough as the [146]result of insufficient kneading? These are delicate questions, of which I, who am no expert in this kind of confectionery, am not competent to judge. Let us have recourse to a master of the pastry-cook’s art. I borrow from the Sacred Beetle the pill which he is beginning to roll in the vivarium. I choose a small one, of the size affected by the Copris. True, it is round; but the Copris’ pills also are pretty often round, even after receiving the egg.

Well, the Sacred Beetle’s loaf, that loaf of irreproachable quality, kneaded by the king of bread-makers, meets with the same fate as mine. At one time it is provided with an egg, at another it is eaten, while no accident ever happens by inadvertence to the exactly similar pills kneaded by the Copris.

That the insect, finding itself in this mixed assembly, should rip open what is still inanimate matter and respect what is already a cradle, that it should discriminate between the lawful and the unlawful, in circumstances such as these, seems to me incapable of explanation, if there be no guide but senses resembling our own. It is useless to say that it is a case of sight: the Beetle works in absolute darkness. Even if she worked in the light, that would not lessen the difficulty. The shape and appearance of the pill are alike in both instances; the clearest sight would be at fault once the pills were mixed up.

It is impossible to suggest that smell has anything to do with it: the substance of the pill does not vary; it is always the produce of the Sheep. Impossible likewise to say that she is exercising the sense of touch. What delicacy of touch can there be under a coat of horn? Besides, the most exquisite sensitiveness would be required. Even if we admit that the insect’s feet, particularly the tarsi, or the palpi, or the antennæ, or anything you please, possess [147]a certain faculty for distinguishing between hard and soft, rough and smooth, round and angular, still our experiment with the Sacred Beetle’s sphere warns us to look where we are going. There surely we had the exact equivalent of the Copris’ sphere—made of the same materials, kneaded to the same consistency, given the same outline—and yet the Copris makes no mistake.

To drag the sense of taste into the problem would be absurd. There remains that of hearing. Later on, I might not deny the possibility that this has something to do with it. When the larva is hatched, the mother, ever attentive, might conceivably hear it nibbling the wall of the cell, but for the present the chamber contains merely an egg; and an egg is always silent.

Then what other means does the mother possess, I will not say of thwarting my machinations—the problem is on a loftier plane and animals are not endowed with special aptitudes in order to dodge an experimenter’s wiles—what other means does she possess of obviating the difficulties attendant upon her normal labours? Do not lose sight of this: she begins by shaping a sphere; and the globular mass often does not differ from the pills that have received the egg, in respect of either form or size.

Nowhere is there peace, not even below ground. When, in a moment of panic, the too-timid mother falls off her sphere and forsakes it to seek refuge elsewhere, how can she afterwards find her ball again and distinguish it from the others, without running the risk of crushing an egg when she is pressing in the top of a pill to make the necessary crater? She needs a safe guide here. What is that guide? I do not know.

I have said it many a time and I say it again: insects possess sense-faculties of exquisite delicacy attuned to [148]their special trade, faculties of which we can form no conception because we have nothing similar within ourselves. A man blind from birth can have no notion of colour. We are as men blind from birth in the face of the unfathomable mysteries that surround us; and myriads of questions arise to which no answer can ever be given.