ONTHOPHAGI AND ONITICELLI

After the notabilities of the Dung-beetle tribe, if we omit the Geotrupes, who belong to a different clan, there remains, within the very limited radius of my observation, the Onthophagus rabble, of which I could gather a dozen different species around my house. What will these small fry teach us?

Even more zealous than their big companions, they are the first that hasten to exploit the heap left by the passing Mule. They come in crowds and stay a long time working under the spread table that gives them shade and coolness. Turn over the heap with your foot. You will be surprised at the swarming population whose presence no outward sign betrayed. The largest are scarce the size of a pea, but some are much smaller still; and these dwarfs are no less busy than the others, no less eager to crumble into dust the filth which, in the interests of the public health, must be cleared away with all speed.

For the more important work of life there is nothing like the humble toilers for realizing vast strength, made up of their joint weaknesses. Swollen by numbers, the next to nothing becomes an enormous total.

Hurrying in detachments at the first news of the event, assisted moreover in their sanitary work by their partners, the Aphodii, who are as weak as they, the tiny Onthophagi [173]soon clear the ground of its dirt. Not that their appetite is equal to the consumption of such plentiful provisions. What food do these pigmies need? A mere atom. But for that atom, selected from among the exudations, search must be made amid the wisps of masticated fodder. Hence, an endless division and dissection of the lump, reducing it to dust which the sun sterilizes and the wind dispels. As soon as the work is done—and very well done—the troop of scavengers goes in search of another refuse-yard. Except for the period of intense cold, which puts a stop to all activity, they are never idle.

And do not run away with the idea that this filthy task entails an inelegant shape and a ragged dress. Our squalor is unknown to the insect. In its world, a navvy dons a sumptuous jerkin; an undertaker decks himself in a triple saffron sash; a wood-cutter works in a velvet coat. In like manner, the Onthophagus has his special gorgeousness. True, the costume is always severe: brown and black are the predominant colours, now dull, now polished as ebony. That is the general groundwork, but how chaste and elegant are the decorative details!

One (O. lemur) has wing-cases of a light chestnut colour, with a semicircle of black dots; a second (O. nuchicornis) has similar chestnut wing-cases covered with splashes of Indian ink not unlike the square Hebrew characters; a third (O. Schreberi), who is a glossy black like that of jet, decks himself with four vermilion cockades; a fourth (O. furcatus) lights up the tip of his short wing-cases with a gleam similar to that of dying embers; many (O. vacca, O. cænobita and others) have corselets and heads bright with the metal sheen of Florentine bronze.

The graver’s work completes the beauty of the dress. Dainty chasing in parallel grooves, delicate embroidery, [174]knotty chaplets are distributed in profusion among nearly all of them. Yes, the little Onthophagi, with their short bodies and their nimble activity, are really pretty to look at.

And then how original are their frontal decorations! These peace-lovers delight in the panoply of war, as though they, the inoffensive ones, thirsted for battle. Many of them crown their heads with threatening horns. Let us mention a couple of the horned ones whose story will occupy us more particularly. I mean, first, the Bull Onthophagus (O. taurus), clad in raven black. He wears a pair of long horns, gracefully curved and branching to either side. No pedigree bull, in the Swiss meadows, can match them for curve or elegance. The second is the Forked Onthophagus (O. furcatus), who is much smaller. His equipment consists of a fork with three vertical prongs.

There you have the two chief subjects of this brief Onthophagus biography. The others are equally worthy of being chronicled. From first to last, they would all supply us with interesting details, some of them even with peculiarities unknown elsewhere; but we must draw the line somewhere in this multitude, which is difficult to observe in the aggregate. And there is this more serious circumstance, that my choice has not been free: I have had to content myself with the few lucky discoveries made as the result of chance encounters out of doors and with the few successful experiments made in the vivarium.

Two species only, the two which I have named, have proved satisfactory in both directions. Let us watch them at work. They will show us the principal features of the manner of life led by the whole tribe, for they occupy the two extremes of the scale of sizes, the Bull Onthophagus being one of the largest and the Forked Onthophagus one of the smallest.[175]

We will speak first of the nest. Contrary to my expectation, the Onthophagi are indifferent nest-builders. With them we find no spheres rolled joyously in the sunshine, no ovoids manipulated laboriously in an underground workshop. Their business, that of reducing filth to dust, appears to give them so much to do that they have no time left for work demanding prolonged patience. They confine themselves to what is strictly necessary and most rapidly obtained.

A perpendicular well is dug, a couple of inches deep, cylindrical in shape and varying in bore according to the size of the well-sinker. The pit of the Forked Onthophagus has the diameter of a lead-pencil; that of the Bull Onthophagus is twice the width. Right at the bottom are the grub’s provisions, plastered against the walls in a tightly-packed heap. The total lack of free space at the sides of the pile shows how the provisioning is done. There is not a sign of a niche, of the least corner that would leave the mother enough liberty of movement to knead and mould her bun. The material therefore is simply pressed down at the bottom of the cylindrical sheath, where it takes the shape of a full thimble.

I dig up some nests of the Forked Onthophagus near the end of July. It is a crude piece of work, which surprises you by its roughness when you think of the neat little worker. Wisps of hay, sticking out anyhow, increase the untidy look of things. The nature of the materials, supplied this time by the Mule, are partly the cause of this ugly appearance.

The length of these nests is fourteen millimetres, the width seven.1 The upper surface is slightly concave, proving that the pressure has been exercised by the mother. [176]The lower end is rounded like the bottom of the well which serves as a mould. I take a needle and with the point of it I pick the rustic structure to pieces. The mass of foodstuff occupies the base, forming the lower two-thirds of the thimble into a compact block; the cell containing the egg is at the top, under a thin, concave lid.

There is nothing fresh about the work of the Bull Onthophagus, which, save for being larger, differs in no way from that of the Forked Onthophagus. I am unacquainted with the insect’s modus operandi. As regards the inner secrets of nest-building, these dwarfs are as reticent as their big colleagues. One alone satisfied my curiosity, or nearly; and then it was not an Onthophagus but a kindred species, the Yellow-footed Oniticellus (O. flavipes).

I capture her in the last week of July, under a heap which a Mule employed in treading out the corn on the thrashing-floor dropped during a rest from work. The thick blanket, transformed by a hot sun into an incomparable incubator, shelters a host of Onthophagi. The Oniticellus is by herself. Her quick retreat down a yawning well attracts my attention. I dig to a depth of about two inches and extract the lady of the house together with her work, the latter in a sadly damaged condition. I can, however, distinguish a sort of bag.

I install the Oniticellus in a tumbler, on a layer of heaped earth, and give her as her nest-building materials what the Sacred Beetles and the Copres prefer, the Sheep’s plastic paste. Caught at the moment when she was about to lay, goaded by the irresistible needs of her ovaries, the mother lends herself very obligingly to my wishes. She lays four eggs in three days. This rapidity, which would doubtless be even greater if my curiosity had not disturbed her in her task, is explained by the simplicity of the work.[177]

The mother goes to the lower surface of the stuff which I have supplied and detaches from the central and softest part a slice sufficient for her plans, removing it all in one piece, by means of a circular section. It is the same method as that employed by the Copris taking from her loaf the wherewithal to make a pellet. There is a pit immediately below, dug in advance. The Oniticellus goes down it with her burden.

I wait half an hour, to give the work time to take shape, and then turn the glass upside down, hoping to surprise the mother in her domestic business. The original little lump is now a bag moulded by pressure against the sides of the well. The mother is at the bottom, motionless, bewildered by my disturbing visit and the intrusion of light. To see her working with her forehead and legs in order to spread the matter, crush it and apply it to its earthen sheath seems to me a very difficult thing to do. I abandon the attempt and restore the glass to its first position.

A little later, I make a second examination, when the mother has left her burrow. The work is now finished. The outward form is that of a thimble fifteen millimetres deep by ten wide.2 The flat end has all the appearance of a lid fitted to the opening and carefully soldered on. The rounded lower half of the thimble is full. This is the grub’s larder. Above is the hatching-chamber, with the egg sticking up from the floor, fixed perpendicularly by one end.

Great is the danger for the Oniticellus and the Onthophagus, offspring of the dog-days, both of them. Their jar of preserves is greatly restricted in volume. Its shape is in no way calculated to reduce evaporation; it is too near the surface of the soil to escape the dangerous dryness [178]of the air. If the cake should harden, the grub will die, after its abstinence has been prolonged to the utmost limits of endurance.

I place in glass tubes, which will represent the native well, a few Onthophagus- and Oniticellus-thimbles, first contriving an opening in the side which will enable me to see what happens within. I close the tubes with a plug of cotton and keep them in a shady part of my study. Evaporation must be very slight in these impermeable and moreover plugged sheaths. Nevertheless it is enough to produce in a few days a degree of dryness which is fatal to feeding.

I see the starvelings remain motionless, unable to bite into the hateful crust; I see them lose their plumpness, I see them wrinkle and shrivel, and at last, in a fortnight’s time, take on all the appearance of death. I replace the dry cotton with wet cotton. The atmosphere in the tubes becomes damp; the thimbles are gradually saturated with the moisture, swell out and soften; and the dying come back to life. They do so to such good purpose that the whole cycle of the metamorphoses is safely accomplished, on condition that the wet cotton be renewed from time to time.

My carefully graduated artificial shower, with its damped cotton to represent the clouds, inspires that return to life. It is like a resurrection. In the normal conditions prevailing in the torrid, rain-grudging month of August, the probability of an equivalent of that shower is almost nil. How then is the fatal drying-up of the victuals avoided? To begin with, there are, so it seems to me, certain gifts bestowed on these little ones so inadequately protected by their mother’s industry against the enemy, drought. I have seen Onthophagus- and Oniticellus-larvæ recover [179]their appetite, their plumpness and their vigour under the wet cotton, after a three weeks’ fast that had reduced them to a wrinkled pilule. This faculty of endurance has its uses: it enables the possessor to await, in a state of lethargy akin to death, the few, very uncertain drops of rain that will put an end to the famine. It comes to the grub’s rescue, but it is not sufficient: the prosperity of a race cannot be based upon privation.

There is something more, therefore; and this is furnished by the mother’s instinct. Whereas the manufacturers of pears and ovoids always dig their burrow at an open spot, with no other protection than the mound of earth flung up, the makers of little thimbles bore their well directly under the material exploited and go by preference to the voluminous droppings of the Horse and the Mule. Under this thick mattress, the soil, protected against sun and wind, keeps fresh and damp for some little time, steeped as it is in the moisture from the dung.

For that matter, the danger does not last long. The egg yields up the grub in less than a week; and the larva attains its full development within a dozen days or so, if nothing untoward happens. This makes about twenty days in all for the critical period of the Onthophagus and the Oniticellus. What does it matter if the walls of the emptied thimble do dry after that! The nymph will be all the better off in a solid casket, which will easily crumble to bits later, when, with the first September rains, the insect effects its release.

In appearance and habits the grub resembles that which the Sacred Beetle and the others have introduced to us. It possesses the same aptitude for defending the cell against the dangerous intrusion of the dry air; the same [180]zeal, the same nimbleness in cementing the least breach with the putty of the intestines; the same knapsack hunching the middle of the back.

The grub of the Oniticellus has the most remarkable hump of all. Would you care to have a quick and yet a faithful sketch of it? Draw a short, wrinkled sausage. About the middle of this sausage, on the side, graft an appendix. There you have the beast, in three almost equal parts. The lower portion is the abdomen; the upper, where you are at first inclined to look for the head, so clearly does it appear to be a continuation of the part below, is the hump, the inordinate, extravagant hump, bigger than caricaturist ever dared conceive in the wildest flights of his imagination. It occupies the place which by rights belongs to the chest and head. Then where are these? Thrust aside by the monstrous knapsack, they constitute a lateral appendage, a mere knob. The strange creature bends at right angles under the weight of its hump.

When nature goes in for the grotesque, she leaves us behind. Is grotesque the right word? I have seen representations of Monkeys adorned with preposterous noses which Rabelais, for all his inspired vision of the huge, never conceived; and this though he invented the nose ‘like the beak of a limbeck, in every part thereof most variously diapered with the twinkling sparkles of crimson blisters budding forth, and purpled with pimples all enamelled with thick-set wheals of a sanguine colour, bordered with gules.’3 I know some who are all scrubby with shock-headed wigs and whiskers and imperials in which every hairy drollery seems to be epitomized; and yet [181]there is not a doubt that noses ‘like the beak of a limbeck’ and bristly faces are highly admired in the simian clan. There is no boundary between the fashionable and the grotesque. It all depends upon the appraiser.

If the grub with the outrageous hump were to show itself in public, it would doubtless represent the supreme expression of the beautiful in the eyes of the Oniticellus and the Onthophagus. Because it is a recluse, nobody sees it. Its charms would remain unknown but for the philosophical observer, who says to himself:

‘Everything is good that harmonizes with the functions to be fulfilled. The grub requires a cement-bag to safeguard its provisions against desiccation; it is born with a knapsack on its back so that it may live.’

Thus is the hump excused and abundantly justified.

Its usefulness is displayed from another point of view. The thimble is of such a niggardly size that the grub consumes it almost entirely. All that remains is a thin layer, a crumbling remnant which would provide no security for the nymph. The ruined dwelling has to be strengthened, to be lined with a new wall. For this purpose, the larva of the Oniticellus empties the whole of its knapsack and gives its cell a complete coating of cement, after the manner of the Sacred Beetle and others.

The grub of the different species of Onthophagi does more artistic work. Placing its putty drop by drop, it constructs a mosaic of lightly-projecting scales, suggesting those of a cedar-cone. When finished, well dried and stripped of the last shreds of the original thimble, the shell thus obtained by the Bull Onthophagus is the size of an average filbert and resembles the pretty cone of the alder-tree. The imitation is so good that I was taken in by it the first time that I handled the curious product when [182]digging in my cages. It needed the contents of the mock alder-cone to show me my mistake. The hump has an artfulness of its own: it was keeping this elegant specimen of stercoral jewellery in reserve for us.

The nymph of the Onthophagi provides us with another surprise. My observations are confined to two species only: the Bull Onthophagus and the Forked Onthophagus; but the difference between the two, in size and shape, is great enough to allow me to generalize and apply the following singular fact to the whole genus.

About the middle of the fore-edge of the corselet the nymph is armed with a very distinct horn, projecting for about one-twelfth of an inch. The horn is transparent, colourless and limp, as are all the budding organs at this period, particularly the legs, the cornicles of the forehead and the mouth-parts. This crystalline protuberance proclaims a future horn as clearly as the mandible is proclaimed by its initial nipple or the wing-case by its sheath. Any insect-collector will understand my amazement. A horn there, on the prothorax! But no Onthophagus wears such a weapon as that! The register of my insect-house duly records the genus of the insect, but I dare not believe it.

The nymph moults. Together with the cast skin, the unfamiliar horn dries up and falls off, leaving not the least trace behind it. My two Onthophagi, recently disguised in strange armour, now have their corselets bare.

This fleeting organ, which disappears without leaving even an excrescence, this temporary horn at a spot destined in the end to be unmailed, gives rise to a few reflections. The Dung-beetles, those placid creatures, generally favour a warlike harness: they love outlandish weapons, halberds, spears, grappling-irons, scimitars. [183]Let us hurriedly recall the horn of the Spanish Copris. No Rhinoceros in the Indian jungles boasts one to compare with it upon his nose. Broad at the base, pointed at the tip, curved like a bow, when the head is lifted the horn bends back till it touches the keel of the obliquely truncated corselet. It might be a harpoon intended for ripping up some monster. Remember also the Minotaur,4 who looks as though he were going to spit his foe with his sheaf of three couched lances, and the Lunary Copris, horned on the forehead, armed with a pike on each shoulder and wearing a corselet notched with little crescents that remind us of the short curved knife of the pork-butcher.

The Onthophagi have a most varied arsenal. One, O. taurus, wears the Bull’s crescent-shaped horns; a second, O. vacca, prefers a wide, short blade, with its point sheathed in a notch in the corselet; a third, O. furcatus, wields a trident; yet another, O. nuchicornis, owns a dagger with a winged handle; and again O. cænobita sports a cavalryman’s sword. The worst-equipped crown their foreheads with a transversal crest, with a pair of cornicles.

What is the good of this panoply? Are we to look upon it as a set of tools, pickaxes, mattocks, pitchforks, spades, levers, which the insect might ply in digging? By no means. The only industrial implements are the forehead and the legs, especially the fore-legs. I have never discovered a Dung-beetle of any sort making use of her weapons either to excavate her burrow or to mix her provisions. Besides, as a rule, the direction of the things alone would prevent their employment as utensils. For a digging-job performed forwards, what would you have a Spanish Copris do with her pickaxe, which points backwards? [184]The powerful horn does not face the obstacle attacked; it turns its back upon it.

The Minotaur’s trident, though arranged in a suitable direction, likewise remains unemployed. When deprived of this armour with a clip of my scissors, the Beetle loses none of his mining-talents; he goes underground quite as easily as his unmutilated fellow. And here is an even more conclusive argument: the mothers, to whose lot the labour of nest-building falls; the mothers, those conspicuous workers, are deprived of these horny growths or possess them only on a greatly reduced scale. They simplify the armour, or reject it entirely, because it is more of an impediment than an assistance to their work.

Are we to look upon them as means of defence? Not that either. The ruminants, the main feeders of the dung-eaters, are also given to wearing frontal armour. The analogy of taste is obvious, though it is impossible for us to suspect its remote reasons. The Ram, the Bull, the Goat, the Chamois, the Stag, the Reindeer and the rest of them are armed with horns and antlers which they use in amorous jousts or for the protection of the threatened herd. The Onthophagi know nothing of these contests. There is no strife among them; and, should danger arise, they content themselves with shamming death by gathering their legs under their abdomen.

Their armour then is a mere ornament, the fine feathers of masculine coquetry. According to life’s law of competition, the best-dressed carry off the palm. Though we may regard those rapiers on the nose as queer, their wearers are of another opinion; and the most eccentric enjoy the highest favour. The smallest extra pimple, springing up by accident, is an added beauty which may [185]decide the choice among the suitors. The best-adorned captivate the mothers, perpetuate the breed and hand down to their offspring the cornicle or the knob that caused their triumph. Thus by degrees was the ornamentation at which the entomologist wonders to-day formed and transmitted from generation to generation, improving as it went.

To this dictum of the evolutionists the nymph of the Onthophagus replies as follows:

‘I have on my back a budding horn, the germ of a bit of ornamentation that can be very handsome, as witness the Bison Bubas, who turns it into a splendid prow-shaped protuberance; witness also various exotic relatives of mine, who lengthen their corselet into a magnificent spur. I possess the wherewithal to bring about a revolution among my kin. If I retained it, my bump, that charming innovation, would relegate my rivals to the second rank; I should be preferred above all others; I should become the founder of a family; and my descendants, completing and improving on my first attempt, would behold the extinction of those antiquated old things. Why should the lump on my back wither purposeless? Why should my endeavour, repeated year after year for centuries, never achieve the promised result?’

Listen to me, O ambitious one! The theorists, it is true, declare that every casual acquisition, however trifling, is handed down and increases if it be profitable; but don’t rely overmuch on that assertion. I do not doubt the advantages which you might gain from a little ornament. What I do very much doubt is the efficacity of time and environment as an evolutionary factor. You will be well-advised to believe that, born in the dim and [186]distant past with a transient callosity, you are continuing and will continue to be born with that rudimentary excrescence without any chance of fixing it, hardening it into a horn or obtaining an additional decoration for your wedding-garment.

Be we men or Dung-beetles, we are all created in the image of an unalterable prototype: the changing conditions of life alter us slightly on the surface but never in the framework of our being. The verdigris of the ages may encrust our medals, but it can give them neither a new image nor a new superscription. Nothing will give me the wings of a bird, desirable though these would be in the midst of our human squalor; nor will anything bestow upon your adult age the triumphal crest which your nymphal knob seemed to prognosticate.

The nymphs of both the Onthophagus and the Oniticellus attain their maturity in some twenty days. During August the adult form appears with the half-white, half-red costume which has become familiar to us from our earlier studies. The normal colouring is fixed pretty quickly. Nevertheless the insect is in no hurry to burst its shell: the difficulty would be too great. It waits for the first showers of September, which will come to its assistance by softening the casket. The liberating rain arrives; and behold, issuing from the earth to rush after food, the joyous small fry of the Onthophagi.

Among the domestic secrets which my cages reveal to me at this period, one above all attracts my attention. I possess at the same time, in separate establishments, the newcomers and the veterans, which last are as brisk and eager in their pursuit of the victuals as are their sons, now banqueting for the first time in the open. The cages are stocked with two generations.[187]

The same synchronizing of fathers and sons is observable among all the Dung-beetles that build their nests in the spring: Sacred Beetles, Copres and Geotrupes. The precaution which I have taken to watch the hatchings and to place the youngsters in a special compartment as and when they appeared confirms this remarkable simultaneity.

It is an entomological principle that the ancestor shall not see his descendants; he dies once the future of his family is assured. By a glorious privilege, the Sacred Beetle and his rivals are allowed to know their successors: fathers and sons meet at the same banquet, not in my cages, where the problems under consideration compel me to keep them separate, but in the open fields. Together they gambol in the sun, together they exploit the patch of dung encountered; and this life of revelry lasts as long as autumn continues to supply fine days.

The cold weather arrives. Sacred Beetles and Copres, Onthophagi and Gymnopleuri dig themselves a burrow, go down into it with provisions, shut themselves in and wait. In January, on a frosty day, I dig into the cages, which have no protection against the inclemencies of the season. I go to work discreetly, so as not to submit all my captives to the harsh test. Those whom I exhume each sit huddled in a shell, beside the remaining provisions. All that the lethargy produced by the cold allows them to do is to move their legs and antennæ a little when I expose them to the sun.

Hardly has the imprudent almond-tree burst into blossom in February, when some of the sleepers awake. Two of the earlier Onthophagi, O. lemur and O. fronticornis, are very common at this time, already crumbling the dung warmed by the sun on the high-road. Soon the festival [188]of spring begins; and all, large and small, newcomers and veterans, hasten to take part in it. The old ones, not all, but at least some of them, the best-preserved, fly off and get married a second time, an unparalleled privilege. They have two families, separated by an interval of a year. They can indeed have three, as is evidenced by the Broad-necked Scarab, who, kept in a cage for three years, gives me every year her collection of pears. Perhaps they even go beyond this. The Dung-beetle tribe has its patriarchs who are truly venerable.