A DUNG-BEETLE OF THE PAMPAS

To travel over the world, by land and sea, from pole to pole; to cross-question life, under every clime, in the infinite variety of its manifestations: that surely would be glorious luck for him that has eyes to see with; and it formed the radiant dream of my young years, at the time when Robinson Crusoe was my delight. These rosy illusions, rich in voyages, were soon succeeded by dull, stay-at-home reality. The jungles of India, the virgin forests of Brazil, the towering crests of the Andes, beloved by the condor, were reduced, as a field for exploration, to a patch of pebble-stones enclosed within four walls.

Heaven forfend that I should complain! The gathering of ideas does not necessarily imply distant expeditions. Jean-Jacques Rousseau herborized with the bunch of chickweed whereon he fed his canary; Bernardin de Saint-Pierre discovered a world on a strawberry-plant that grew by accident in a corner of his window; Xavier de Maistre, using an arm-chair by way of post-chaise, made one of the most famous of journeys around his room.

This manner of seeing country is within my means, always excepting the post-chaise, which is too difficult to drive through the brambles. I go the circuit of my [100]enclosure over and over again, a hundred times, by short stages; I stop here and I stop there; patiently, I put questions; and, at long intervals, I receive some scrap of a reply.

The smallest insect village has become familiar to me: I know each fruit-branch where the Praying Mantis perches; each bush where the pale Italian Cricket strums amid the calmness of the summer nights; each wad-clad blade of grass scraped by the Anthidium, that maker of cotton bags; each cluster of lilac worked by the Megachile, the leaf-cutter.

If cruising among the nooks and corners of the garden do not suffice, a longer voyage shows ample profit. I double the cape of the neighbouring hedges and, at a few hundred yards, enter into relations with the Sacred Beetle, the Capricorn, the Geotrupe, the Copris, the Dectus, the Cricket, the Green Grasshopper, in short, with a host of tribes the unfolding of whose story would exhaust a human life. Certainly, I have plenty, I have too much to do with my near neighbours, without going and wandering in distant regions.

And then, besides, roaming the world, scattering one’s attention over a host of subjects, is not observing. The travelling entomologist can stick numerous species, the joy of the collector and the nomenclator, into his boxes; but to gather circumstantial documents is a very different matter. A Wandering Jew of science, he has no time to stop. Where a prolonged stay would be necessary to study this or that fact, he is hurried by the next stage. We must not expect the impossible of him in these conditions. Let him pin his specimens to cork tablets, let him steep them in tafia jars and leave to the sedentary the patient observations that require time.[101]

This explains the extreme penury of history outside the dry descriptions of the nomenclator. Overwhelming us with its numbers, the exotic insect nearly always preserves the secret of its manners. Nevertheless, it were well to compare what happens under our eyes with that which happens elsewhere; it were excellent to see how, in the same corporation of workers, the fundamental instinct varies with climatic conditions.

Then my travelling regrets return, vainer to-day than ever, unless one could find a seat on the carpet of which we read in the Arabian Nights, the famous carpet whereon one had but to sit to be carried whithersoever he pleased. O marvellous conveyance, far preferable to Xavier de Maistre’s post-chaise! If only I could find a little corner on it, with a return-ticket!

I do find it. I owe this unexpected good fortune to a Christian Brother, to Brother Judulian, of the Lasalle College at Buenos Ayres. His modesty would be offended by the praises which his debtor owes him. Let us simply say that, acting on my instructions, his eyes take the place of mine. He seeks, finds, observes, sends me his notes and his discoveries. I observe, seek and find with him, by correspondence.

It is done: thanks to this first-rate collaborator, I have my seat on the magic carpet. Behold me in the pampas of the Argentine Republic, eager to draw a parallel between the industry of the Dung-beetles of Sérignan2 and that of their rivals in the western hemisphere.

A glorious beginning! An accidental find procures me, to start with, Phanæus Milo, a magnificent insect, blue-black all over. The corselet of the male juts forward, over the head, in a short, broad, flattened [102]horn, ending in a trident. The female replaces this ornament with simple folds. Both carry, in front of their shield, two spikes which form a trusty digging-implement and also a scalpel for dissecting. The insect’s squat, sturdy, four-cornered build resembles that of Onitis Olivieri, one of the rarities of the neighbourhood of Montpellier.

If similarity of shape implied parity of work, we ought unhesitatingly to attribute to Phanæus Milo short, thick puddings like those made by Olivier’s Onitis. Alas, structure is a bad guide where the instinct is concerned! The square-chined, short-legged Dung-worker excels in the art of manufacturing gourds. The Sacred Beetle himself supplies none that are more perfect nor, above all, more capacious.

Fig. 8.—Phanæus Milo.

The thick-set insect astonishes me with the elegance of its work, which is irreproachable in its geometry: the neck is less slender, but nevertheless combines grace with strength. The model seems derived from some Indian calabash, the more so as the neck opens wide and the belly is engraved with an elegant guilloche, produced by the insect’s tarsi. One seems to see a pitcher protected by a wicker-work covering. The whole is able to attain and even exceed the size of a hen’s egg.

It is a very curious piece of work and of a rare perfection, especially when we consider the artist’s clumsy and massive build. Once again, the tool does not make the [103]workman, among Dung-beetles any more than among ourselves. To guide the modeller there is something better than a set of tools: there is what I would call the bump, the genius of the animal.

Phanæus Milo laughs at difficulties. He does more: he laughs at our classifications. The word Dung-beetle implies a lover of dung. He sets no value on it, either for his own use or for that of his offspring. What he wants is the sanies of corpses. He is to be found under the carcasses of birds, dogs or cats, in the company of the undertakers-in-ordinary. The gourd of which I give a drawing overleaf was lying in the earth under the remains of an owl.

Let him who will explain this conjunction of the appetites of the Necrophore with the talents of the Scarab. As for me, baffled by tastes which no one would suspect from the mere appearance of the insect, I give it up.

I know in my neighbourhood one Dung-beetle and one alone who also works among the remains of dead bodies. This is Onthophagus Ovatus (Lin.), a constant frequenter of dead moles and rabbits. But the dwarf undertaker does not on that account scorn stercoraceous fare: he feasts upon it like the other Onthophagi. Perhaps there is a two-fold diet here: the bun for the adult; the highly-spiced, far-gone meat for the grub.

Similar facts are encountered elsewhere with different tastes. The predatory Hymenopteron takes her fill of honey drawn from the nectaries of the flowers, but feeds her little ones on game. Game first, then sugar, for the same stomach. How that digestive pouch must change on the road! And yet no more than our own, which scorns in later life that which delighted it when young.

Fig. 9.—Work of Phanæus Milo.

A, the whole piece, actual size. B, the same opened, showing the pill of sausage-meat, the clay gourd, the chamber containing the egg the ventilating-shaft.

Let us now examine the work of Phanæus Milo [104]more thoroughly. The calabashes came into my hands in a state of complete desiccation. They are very nearly as hard as stone; their colour favours a pale chocolate. Neither inside nor out does the lens discover the small fibrous particle pointing to a residuum of grasses. The strange Dung-beetle does not, therefore, employ the bovine cakes, nor anything similar; he handles products of another class, which are pretty difficult to specify at first.

Held to the ear and shaken, the object sounds a little as would the shell of a dry fruit with a stone lying free inside it. Does it contain the grub, shrivelled by desiccation? Does it contain the dead insect? I thought so, [105]but I was wrong. It contains something much better than that for our instruction.

I carefully rip up the gourd with the point of the knife. Under a homogeneous outer wall, the thickness of which reaches as much as two centimetres3 in the largest of my three specimens, is encased a spherical kernel, which fills the cavity exactly, but without sticking to the wall at any part. The trifle of free scope allowed to this kernel accounts for the rattling which I heard when shaking the piece.

The kernel does not differ from the wrapper in the colour and general appearance of its bulk. But let us break it and examine the shreds. I recognize tiny fragments of gold, flocks of down, threads of wool, scraps of meat, the whole drowned in an earthy paste resembling chocolate.

Placed on a glowing coal, this paste, shredded under the lens and deprived of its particles of dead bodies, becomes much darker, is covered with shiny bubbles and sends forth puffs of that acrid smoke in which we easily recognize burnt animal matter. The whole mass of the kernel, therefore, is strongly impregnated with sanies.

Treated in the same manner, the wrapper also turns dark, but not to the same extent; it hardly smokes; it is not covered with jet-black bubbles; lastly, it does not anywhere contain shreds of carcasses similar to those in the central nut. In both cases, the residuum of the calcination is a fine, reddish clay.

This brief analysis tells us all about Phanæus Milo’s table. The fare served to the grub is a sort of vol-au-vent. The sausage-meat consists of a mince of all that the two scalpels of the shield and the toothed knives of the fore-legs have been able to cut away from the carcass: [106]hair and down, crushed ossicles, strips of flesh and skin. Now hard as brick, the thickening of that mince was originally a jelly of fine clay soaked in the juice of corruption. Lastly, the puff-paste crust of our vol-au-vent is here represented by a covering of the same clay, less rich in extract of meat than the other.

The pastry-cook gives his pie an elegant shape; he decorates it with rosettes, with twists, with scrolls. Phanæus Milo is no stranger to these culinary æsthetics. He turns the crust of his vol-au-vent into a handsome gourd, ornamented with a finger-print guilloche.

The outer covering, a disagreeable crust, insufficiently steeped in savoury juices, is not, we can easily guess, intended for consumption. It is possible that, somewhat later, when the stomach becomes robust and is not repelled by coarse fare, the grub scrapes a little from the wall of its pie; but, taken as a whole, until the adult insect emerges, the calabash remains intact, having acted as a safeguard of the freshness of the mince-meat at first and as a protecting box for the recluse from start to finish.

Above the cold pasty, right at the base of the neck of the gourd, is contrived a round cell with a clay wall continuing the general wall. A fairly thick floor, made of the same material, separates it from the store-room. It is the hatching-chamber. Here is laid the egg, which I find in its place, but dried up; here is hatched the worm, which, to reach the nourishing ball, must previously open a trap-door through the partition separating the two storeys.

The worm is born in a little box surmounting the nourishing pile, but not communicating with it. The budding grub must, therefore, at the opportune moment, itself pierce the covering of the pot of preserves. As a [107]matter of fact, later, when the worm is on the sausage-meat, we find the floor perforated with a hole just large enough for it to pass through.

Wrapped all round in a thick casing of pottery, the meat keeps fresh as long as is required by the duration of the hatching-process, a detail which I have not ascertained; in its cell, which is also of clay, the egg lies safe. Capital: so far, all is well. Phanæus Milo is thoroughly acquainted with the mysteries of fortification and the danger of victuals evaporating too soon. There remain the breathing requirements of the germ.

To satisfy these, the insect has been equally well-inspired. The neck of the calabash is pierced, in the direction of its axis, with a tiny channel which would admit at most the thinnest of straws. Inside, this conduit opens at the top of the dome of the hatching-chamber; outside, at the tip of the nipple, it spreads into a wide mouth-piece. This is the ventilating-shaft, protected against intruders by its extreme narrowness and by grains of dust which obstruct it a little, without stopping it up. It is simply marvellous, I said. Was I wrong? If a construction of this sort is a fortuitous result, we must admit that blind chance is gifted with extraordinary foresight.

How does the awkward insect manage to carry so delicate and complex a piece of building through? Exploring the pampas as I do through the eyes of an intermediary, my only guide in this question is the structure of the work, a structure whence we can deduct the workman’s methods without going far wrong. I therefore imagine the labour to proceed like this: a small carcass is found, the oozing of which has softened the underlying loam. The insect collects more or less of this loam, [108]according to the richness of the vein. There are no precise limits here. If the plastic material abound, the collector is lavish with it and the provision-box becomes all the more solid. Then enormous calabashes are obtained, exceeding a hen’s egg in volume and formed of an outer wall a couple of centimetres thick.4 But a mass of this description is beyond the strength of the modeller, is badly handled and betrays, in its outline, the clumsiness of an over-difficult task. If the material be rare, the insect confines its harvesting to what is strictly necessary; and then, freer in its movements, it obtains a magnificently regular gourd.

Fig. 10.—Work of Phanæus Milo: the largest of the gourds observed (natural size).

The loam is probably first kneaded into a ball and then scooped out into a large and very thick cup, by means of the pressure of the fore-legs and the work of the shield. [109]Even thus do the Copris and the Sacred Beetle act when preparing, on the top of their round ball, the bowl in which the egg will be laid before the final manipulation of the ovoid or pear.

In this first business, Phanæus is simply a potter. So long as it be plastic, any clay serves his turn, however meagrely it be saturated with the juices emanating from the carcass.

He now becomes a pork-butcher. With his toothed knife, he carves, he saws some tiny shreds from the rotten animal; he tears off, cuts away what he deems best suited to the grub’s entertainment. He collects all these fragments and mixes them with choice loam in the spots where the sanies abounds. The whole, cunningly kneaded and softened, becomes a ball obtained on the spot, without any rolling process, in the same way as the globe of the other pill-manufacturers. Let us add that this ball, a ration calculated by the needs of the grub, is very nearly constant in size, whatever the thickness of the final calabash. The sausage-meat is now ready. It is set in place in the wide-open clay bowl. Loosely packed, without compression, the food will remain free, will not stick to its wrapper.

Next, the potter’s work is renewed. The insect presses the thick lips of the clayey cup, rolls them out and applies them to the forcemeat preparation, which is eventually contained by a thin partition at the top and by a thick layer every elsewhere. A large circular pad is left on the top partition, which is slender in view of the weakness of the grub that is to perforate it later, when making for the provisions. Manipulated in its turn, this pad is converted into a hemispherical hollow, in which the egg is forthwith laid.[110]

The work is finished by rolling out and joining the edges of the little crater, which closes and becomes the hatching-chamber. Here, especially, a delicate dexterity becomes essential. At the time that the nipple of the calabash is being shaped, the insect, while packing the material, must leave the little channel which is to form the ventilating-shaft, following the line of the axis. This narrow conduit, which an ill-calculated pressure might stop up beyond hope of remedy, seems to me extremely difficult to obtain. The most skilful of our potters could not manage it without the aid of a needle, which he would afterwards withdraw. The insect, a sort of jointed automaton, obtains its channel through the massive nipple of the gourd without so much as a thought. If it did give it a thought, it would not succeed.

The calabash is made: there remains the decoration. This is the work of patient after-touches which perfect the curves and leave on the soft loam a series of stippled impressions similar to those which the potter of prehistoric days distributed with the end of his thumb over his big-bellied jars.

That ends the work. The insect will begin all over again under a fresh carcass; for each burrow has one calabash and no more, even as with the Sacred Beetle and her pears.