The Mason-Wasps

[[1]]

CHAPTER I

THE EUMENES

A wasp-like garb of black and yellow; a slender, graceful figure; wings that are not spread flat when resting, but are folded lengthwise in two; the abdomen a sort of chemist’s retort, swelling into a gourd and fastened to the thorax by a long neck which first distends into a pear and then shrinks to a thread; a leisurely and silent flight; lonely habits. There we have a summary sketch of the Eumenes. My part of the country possesses two species: the larger E. Amadei, Lep., measures nearly an inch in length; the other, E. pomiformis, Fabr.,[1] is a reduction of the first to half the scale.

Similar in form and colouring, both possess a like talent for architecture; and this [[2]]talent is expressed in a work of the highest perfection, which charms the most untutored eye. Their dwelling is a masterpiece. And yet the Eumenes follow the profession of arms, which is unfavourable to artistic effort: they stab and sting a victim; they pillage and plunder. They are predatory Wasps, victualling their larvæ with caterpillars. It must be interesting to compare their habits with those of the operator on the Grey Worm.[2] Though the quarry—caterpillars in either case—remain the same, instinct, which is liable to vary with the species, may have fresh glimpses in store for us. Besides, the edifice built by the Eumenes in itself deserves inspection.

The Hunting Wasps whose story we have told hitherto[3] are wonderfully well-versed in the art of wielding the lancet; they astound us with their surgical methods, which they [[3]]seem to have learnt from some physiologist who allows nothing to escape him; but these skilful slayers have no merit as builders of dwelling-houses. What is their home, in point of fact? An underground passage, with a cell at the end of it; a gallery, an excavation, a shapeless cave. It is miner’s work, navvy’s work: vigorous sometimes, artistic never. They use the pick for loosening, the crowbar for shifting, the rake for extracting the materials, but never the trowel for laying. Now in the Eumenes we see real masons, who build their houses bit by bit with stone and mortar and run them up in the open, either on firm rock or on the shaky support of a bough. Hunting alternates with architecture; the insect is a Nimrod or a Vitruvius[4] by turns.

And, first of all, what sites do these builders select for their homes? Should you pass some little garden-wall, facing south, in a sun-scorched corner, look at the stones which are not covered with plaster, look at them one by one, especially the largest; examine the masses of boulders, at no great height from the ground, where the fierce rays have heated them to the temperature of a Turkish [[4]]bath; and perhaps, if you search long enough, you will light upon the structure of Eumenes Amadei. The insect is scarce and lives apart; a meeting is an event upon which we must not count with too great confidence. It is an African species and loves the heat that ripens the carob and the date. It haunts the sunniest spots and selects rocks or firm stones as a foundation for its nest. Sometimes also, but seldom, it copies the Chalicodoma of the Walls[5] and builds upon an ordinary pebble.

E. pomiformis is much more common and is comparatively indifferent to the nature of the foundation on which she constructs her cell. She builds on walls, on isolated stones, on the inner wooden surface of half-closed shutters; or else she adopts an aerial base, the slender twig of a shrub, the withered sprig of a plant of some sort. Any form of support serves her purpose. Nor does she trouble about shelter. Less chilly than her African cousin, she does not shun the unprotected spaces exposed to every wind that blows.

When erected on a horizontal surface, where nothing interferes with it, the structure [[5]]of E. Amadei is a symmetrical cupola, a spherical skull-cap, having at the top a narrow passage just wide enough for the insect and surmounted by a neatly-funnelled neck. It suggests the round hut of the Eskimo or of the ancient Gael, with its central chimney. An inch, more or less, represents the diameter; three-quarters of an inch the height. When the support is a perpendicular plane, the building still retains the domed shape, but the entrance- and exit-funnel opens at the side, upwards. The floor of this apartment calls for no labour: it is supplied direct by the bare stone.

Having chosen the site, the builder erects a circular fence about an eighth of an inch thick. The materials consist of mortar and small stones. The insect selects its stone-quarry in some well-trodden path or on some neighbouring highroad, at the driest, hardest spots. With its mandibles, it scrapes together a small quantity of dust and soaks it with saliva until the whole becomes a regular hydraulic mortar which soon sets and is no longer susceptible to damp. The Mason-bees have shown us a similar exploitation of the beaten paths and of the road-mender’s macadam. All these open-air builders, all these erectors of monuments exposed [[6]]to wind and weather require an exceedingly dry stone-dust; otherwise the material, already moistened with water, would not properly absorb the liquid that is to give it cohesion; and the edifice would soon be wrecked by the rains. They possess the sense of discrimination shown by the plasterer, who rejects plaster injured by the wet. We shall see presently how the insects that build under cover avoid this laborious macadam-scraping and give the preference to fresh earth already reduced to a paste by its own dampness. When common lime answers our purpose, we do not trouble about Roman cement. Now Eumenes Amadei requires a first-class cement, even superior to that of the Chalicodoma of the Walls, for the work, when finished, does not receive the thick outer casing wherewith the Mason-bee protects her cluster of cells. And therefore the cupola-builder, as often as she can, uses the highway as her stone-pit.

With the mortar, bricks are needed. These are bits of gravel of an almost unvarying size—that of a pepper-corn—but of a shape and kind that differ greatly, according to the places worked. Some are sharp-cornered, with facets determined by chance fractures; some are round, polished [[7]]by friction under water. Some are of limestone, others of flinty material. The favourite stones, when the neighbourhood of the nest permits, are smooth, semitransparent little lumps of quartz. These are selected with minute care. The insect weighs them, so to say, measures them with the compass of its mandibles and does not accept them until after making sure that they possess the requisite qualities of size and hardness.

A circular fence, we were saying, is begun on the bare rock. Before the mortar sets, which does not take long, the mason, as the work advances, sticks a few stones into the soft mass. She dabs them half-way into the cement, so as to leave them jutting out to a large extent, without penetrating to the inside, where the wall must remain smooth for the sake of the larva’s comfort. If necessary, she adds a little plaster, to tone down any inner excrescences. The solidly-embedded stonework alternates with the pure mortarwork, of which each fresh course receives its facing of tiny encrusted pebbles. As the edifice is raised, the builder slopes the construction a little towards the centre and fashions the curve which will give the spherical shape. We [[8]]employ arched centerings to support the masonry of a dome while building; the Eumenes, more daring than we, erects her cupola without any scaffolding.

A round opening is contrived at the top; and above this opening rises a funnelled mouth built of pure cement. It might be the graceful neck of some Etruscan vase. When the cell is victualled and the egg laid, the mouth is closed with a cement plug; and in this plug is set a little pebble, one alone, no more: the ritual never varies. This work of rustic architecture has naught to fear from the inclemencies of the weather; it does not yield to the pressure of the fingers; it resists the knife that attempts to remove it without breaking it. Its nipple-shape and the bits of gravel wherewith it bristles all over the outside remind one of certain cromlechs of olden time, of certain tumuli whose domes are strewn with Cyclopean blocks of stone.

Such is the appearance of the edifice when the cell stands alone; but the Wasp nearly always fixes other domes against her first, to the number of five or six or more. This shortens the labour by allowing her to use the same partition for two adjoining rooms. The original elegant symmetry is lost and [[9]]the whole now forms a cluster which, at first sight, might be merely a clod of dry mud, sprinkled with little pebbles. But examine the shapeless mass more closely; and we perceive the number of chambers composing the habitation with the funnelled mouths, each quite distinct and each furnished with its gravel stopper set in the cement.

The Chalicodoma of the Walls employs the same building-methods as Eumenes Amadei: in the courses of cement, she fixes, on the outside, small stones of minor bulk. Her work begins by being a turret of rustic art, not without a certain prettiness; then, when the cells are placed side by side, the whole construction degenerates into a lump governed apparently by no architectural rule. Moreover, the Mason-bee covers her mass of cells with a thick layer of cement, which conceals the original rockwork edifice. The Eumenes does not resort to this general coating: her building is too strong to need it; she leaves the pebbly facings uncovered, as well as the entrances to the cells. The two sorts of nests, though constructed of similar materials, are therefore easily distinguished.

The Eumenes’ cupola is a piece of artist’s work; and the artist would be sorry to hide [[10]]her masterpiece under whitewash. I crave forgiveness for a suggestion which I advance with all the reserve befitting so delicate a subject. Would it not be possible for the cromlech-builder to take a pride in her handiwork, to look upon it with some affection and to feel gratified by this evidence of her cleverness? Might there not be an insect science of æsthetics? I seem at least to catch a glimpse, in the Eumenes, of a propensity to beautify her product. The nest must be first and foremost a solid habitation, an inviolable stronghold; but, should ornament intervene without jeopardizing the power of resistance, will the worker remain indifferent to it? Who could say?

Let us set forth the facts. The orifice at the top, if left as a mere hole, would suit the purpose quite as well as an elaborate door: the insect would lose nothing in regard to facilities for coming and going and would gain by shortening the labour. Yet we find, on the contrary, the mouth of an amphora, gracefully curved, worthy of a potter’s wheel. Choice cement and careful work are needed for the confection of its slender, funnelled shaft. Why this nice finish, [[11]]if the builder be wholly absorbed in the solidity of her work?

Here is another detail: among the bits of gravel employed for the outer covering of the cupola, grains of quartz predominate. They are polished and translucent; they glitter slightly and please the eye. Why are these little pebbles preferred to chips of limestone, when both materials exist in equal abundance around the nest?

A yet more remarkable feature: we find pretty often, encrusted on the dome, a few tiny empty Snail-shells, bleached by the sun. The species usually selected by the Eumenes is one of the smaller Helices, Helix strigata, frequent on our parched slopes. I have seen nests where this Helix took the place of pebbles almost entirely. They were like boxes made of shells, the work of a patient hand.

A comparison suggests itself. Certain Australian birds, notably the Bower-birds, build themselves covered walks or arbours with interwoven twigs and decorate the two entrances to the portico by strewing the threshold with anything that they can find in the shape of glittering, polished or bright-coloured objects. Every doorsill is a cabinet [[12]]of curiosities where the collector gathers smooth pebbles, variegated shells, empty Snail-shells, Parrots’ feathers, bones that have come to look like sticks of ivory. Even the odds and ends mislaid by man find a home in the bird’s museum, where we see pipe-stems, brass buttons, strips of cotton stuff and stone axe-heads.

The collection at either entrance to the bower is large enough to fill half a bushel. As these things are of no use to the bird, its only motive for accumulating them must be an art-lover’s hobby. Our common Magpie has similar tastes: any shiny thing that he comes upon he picks up, hides and hoards.

Well, the Eumenes, who shares this passion for bright pebbles and empty Snail-shells, is the Bower-bird of the insect world; but she is a more practical collector, knows how to combine the useful and the ornamental and employs her discoveries in the construction of her nest, which is both a fortress and a museum. When she finds bits of translucent quartz, she rejects everything else: the building will be all the prettier for them. When she comes across a little white shell, she hastens to beautify her dome with it; should fortune smile and empty Snail-shells [[13]]abound, she encrusts the whole fabric with them, until it becomes the supreme expression of her artistic taste. Is this so or not? Who shall decide?

The nest of Eumenes pomiformis is the size of an average cherry and constructed of pure mortar, without any outer pebblework. Its shape is exactly similar to that which we have just described. When built upon a large enough horizontal base, it is a dome with a central neck, funnelled like the mouth of an urn. But, when the foundation is reduced to a mere point, as on the twig of a shrub, the nest becomes a spherical capsule, always, of course, surmounted by a neck. It is then a miniature specimen of exotic pottery, a big-bellied alcarraza. Its thickness is very slight, less than that of a sheet of paper; it crushes under the least finger-pressure. The outside is not quite even. It displays wrinkles and seams, due to the different courses of mortar, or else knotty projections distributed almost concentrically.

Both Wasps accumulate caterpillars in their coffers, whether domes or jars. Let us give an abstract of the bill of fare. These documents, for all their dryness, possess a value: they will enable whoso [[14]]cares to interest himself in the Eumenes to perceive to what extent instinct modifies the diet, according to place and season. The food is plentiful but lacks variety. It consists of tiny caterpillars, by which I mean the grubs of small Butterflies or Moths. This is proclaimed by the structure, for we observe the usual caterpillar organism in the prey selected by either Wasp. The body is composed of twelve segments, not including the head. The first three have true legs, the next two are legless, then come four segments with prolegs, two legless segments and, lastly, a terminal segment with prolegs. It is exactly the same organization which we saw in the Ammophila’s Grey Worm.

My old notes give the following description of the caterpillars found in the nest of E. Amadei: a pale-green or, less often, yellowish body covered with short white hairs; head wider than the front segment, dead-black and also bristling with hairs. Length: 16 to 18 millimetres;[6] width: about 3 millimetres.[7] It is more than a quarter of a century since I jotted down this descriptive sketch; and today, at Sérignan, I [[15]]find in the Eumenes’ larder the same sort of game that I saw long ago at Carpentras. Time and distance have not altered the nature of the provisions.

I know one exception and one alone in this fidelity to the ancestral diet. My observations mention a single dish that differs greatly from those which accompany it. This is a caterpillar of the Looper group[8] with only three pairs of prolegs, placed under the eighth, ninth and twelfth segments. The body tapers slightly at either end, is contracted at the junction of the different rings and is pale green with faint black veinings, visible under the magnifying-glass, and a few sparse black cilia. Length: 15 millimetres;[9] width: 2½ millimetres.[10]

E. pomiformis also has her preferences. Her game consists of small caterpillars about 7 millimetres long by 1⅓ wide.[11] The body is pale green, pretty sharply contracted at the junction of the segments. The head is narrower than the rest of the body and is spotted with brown. Pale ocellated [[16]]circles are distributed in two transversal rows over the middle segments and have a black dot in the centre, surmounted by a black cilium. On the third and fourth and also on the penultimate segment, each circle has two black dots and two cilia. This is the rule.

The exception is supplied by two head of game in the whole course of my observations. These two had a pale yellow body, with five longitudinal brick-red stripes and a few very rare cilia. Head and prothorax brown and shiny; length and diameter as above.

The number of pieces served for the meal of each larva interests us more than the quality. In the cells of E. Amadei I find sometimes five caterpillars and sometimes ten, which means a difference of a hundred per cent in the quantity of the food, for the pieces are of exactly the same size in both cases. Why this unequal supply, which gives a double portion to one larva and a single portion to another? The consumers have the same appetite: what one nurseling demands a second must demand, unless there be here a menu differing according to the sexes. In the perfect stage, the males are smaller than the females, are hardly [[17]]half as much in weight or volume. The amount of victuals, therefore, required to bring them to their final development may be reduced by one-half. In that case, the well-stocked cells belong to females; the others, more meagrely supplied, belong to males.

But the egg is laid when the provisions are stored; and this egg has a determined sex, although the most minute examination is not able to discover the differences which will decide the hatching of a female or a male. We are therefore needs driven to this strange conclusion: the mother knows beforehand the sex of the egg which she is about to lay;[12] and this knowledge enables her to fill the larder according to the appetite of the future grub. What a strange world, so wholly different from ours! We fall back upon a special sense to explain the Ammophila’s hunting; what can we fall back upon to account for this intuition of the future? Can the theory of chances play a part in the hazy problem? If nothing is logically arranged with a foreseen object, how is this clear vision of the invisible acquired? [[18]]

The capsules of E. pomiformis are literally crammed with game. It is true that the morsels are very small. My notes speak of fourteen green caterpillars in one cell and sixteen in a second. I have no other information about the integral diet of this Wasp, whom I have neglected somewhat, preferring to study her cousin, the builder of rockwork domes. As the two sexes differ in size, though not so greatly as in E. Amadei, I am inclined to think that those two well-filled cells belonged to females and that the males’ cells must have a less sumptuous table. Not having seen for myself, I am content to set down this mere suspicion.

What I have seen and often seen is the pebbly nest, with the larva inside and the provisions partly consumed. To continue the rearing at home and follow my charges’ progress from day to day was a business which I could not resist; besides, so far as I was able to see, it was easily managed. I had had some practice in this foster-father’s trade; my association with the Bembex, the Ammophila, the Sphex[13] and many others had turned me into a passable insect-breeder. [[19]]I was no novice in the art of dividing an old pen-box into compartments in which I laid a bed of sand and on this bed the larva, with her provisions, delicately removed from the maternal cell. Success was almost certain at each attempt: I used to watch the larvæ at their meals, I saw my nurselings grow up and spin their cocoons. Relying upon the experience thus gained, I reckoned on success in raising my Eumenes.

The results, however, in no way answered to my expectations. All my endeavours failed; and the larva allowed itself to die a piteous death without touching its provisions.

I ascribed my reverse to this, that and the other cause: perhaps I had injured the frail grub when demolishing the fortress; perhaps a splinter of masonry bruised it when I forced open the hard dome with my knife; perhaps a too-sudden exposure to the sun surprised it when I withdrew it from the darkness of its cell; the open air again might have dried up its moisture. I did the best I could to remedy all these probable reasons of failure. I went to work with every possible caution in breaking open the home; I cast the shadow of my body [[20]]over the nest, to save the grub from sunstroke; I at once transferred larva and provisions into a glass tube and placed this tube in a box which I carried in my hand, to minimize the jolting on the journey. Nothing was of avail: the larva, when taken from its dwelling, always pined away and died.

For a long time, I persisted in explaining my failure by the difficulties attending the removal. The cell of Eumenes Amadei is a strong casket which cannot be forced without sustaining a shock; and the demolition of a work of this kind entails such varied accidents that we are always liable to think that the grub has been bruised by the wreckage. As for carrying home the nest intact on its support, with a view to opening it with greater care than is permitted by a rough and ready operation in the fields, that is out of the question: the nest nearly always stands on an immovable rock or on some big stone forming part of a wall. If I failed in my attempts at rearing, it was because the larva had suffered when I was breaking up her house. The reason seemed a good one; and I let it go at that.

In the end, another idea occurred to me and made me doubt whether my rebuffs [[21]]were always due to clumsy accidents. The Eumenes’ cells are crammed with game: there are ten caterpillars in the cell of E. Amadei and fifteen in that of E. pomiformis. These caterpillars, stabbed no doubt, but stabbed in a fashion unknown to me, are not entirely motionless. The mandibles seize upon what is presented to them, the body buckles and unbuckles, the hinder half lashes out briskly when stirred with the point of a needle. At what spot is the egg laid amid that swarming mass, where thirty mandibles can make a hole in it, where a hundred and twenty pair of legs can tear it? When the victuals consist of a single head of game, these perils do not exist; and the egg is laid on the victim not at hazard, but upon a judiciously chosen spot. Thus, for instance, the Hairy Ammophila fixes hers, by one end, across the Grey Worm, on the side of the first prolegged segment. The egg hangs over the caterpillar’s back, away from the legs, whose proximity might be dangerous. The worm, moreover, stung in the greater number of its nerve-centres, lies on its side, motionless and incapable of bodily contortions or sudden jerks of its hinder segments. If the mandibles try to snap, if the legs give [[22]]a kick or two, they find nothing in front of them: the Ammophila’s egg is in the opposite direction. The little grub is thus able, as soon as it hatches, to dig into the giant’s belly in full security.

How different are the conditions in the Eumenes’ cell! The caterpillars are imperfectly paralysed, perhaps because they have received but a single stab; they toss about when touched with a pin; they are bound to wriggle when bitten by the larva. If the egg is laid on one of them, this first morsel will, I admit, be consumed without danger, on condition that the point of attack be wisely chosen; but there remain others which are not deprived of every means of defence. Let a movement take place in the mass; and the egg, shifted from the upper layer, will tumble into a trap of legs and mandibles. The least thing is enough to jeopardize its existence; and this least thing has every chance of being brought about in the disordered heap of caterpillars. The egg, a tiny cylinder, transparent as crystal, is extremely delicate: a touch withers it; the least pressure crushes it.

No, its place is not in the mass of provisions, for the caterpillars, I repeat, are [[23]]not sufficiently harmless. Their paralysis is incomplete, as is proved by their contortions when I irritate them and evidenced moreover by a very important fact. I have sometimes taken from the cell of Eumenes Amadei a few head of game half-transformed into chrysalids. It is evident that the transformation was effected in the cell itself and therefore after the operation which the Wasp had performed upon them. Whereof does this operation consist? I cannot say precisely, never having seen the huntress at work. The sting most certainly has played its part; but where? And how often? This is what we do not know. What we can declare is that the torpor is not very profound, inasmuch as the patient sometimes retains enough vitality to shed its skin and become a chrysalis. Everything thus tends to make us ask by what stratagem the egg is shielded from danger.

This stratagem I longed to discover; I would not be put off by the scarcity of nests, by the irksomeness of the search, by the risk of sunstroke, by the time taken up in the vain breaking open of unsuitable cells; I meant to see and I saw. Here is my method: with the point of a knife and a pair of nippers, I make a side opening, a window, [[24]]beneath the dome of E. Amadei and E. pomiformis. I work with the greatest care, so as not to injure the recluse. I used to attack the cupola from the top; I now attack it from the side. I stop when the breach is large enough to allow me to see the state of things within.

What is this state of things? I pause to give the reader time to reflect and to think out for himself a means of safety that will protect the egg and afterwards the grub in the perilous conditions which I have set forth. Seek, think and contrive, such of you as have inventive minds. Have you guessed it? Do you give it up? I may as well tell you.

The egg is not laid upon the provisions; it hangs from the top of the cupola by a thread which vies with that of a Spider’s web for slenderness. The dainty cylinder quivers and swings at the least breath; it reminds me of the famous pendulum hung from the dome of the Panthéon to prove the rotation of the earth. The victuals are heaped up underneath.

Second act of this wondrous spectacle. In order to witness it, we must open a window in cell after cell until fortune deigns to smile upon us. The larva is hatched and [[25]]already fairly large. Like the egg, it hangs perpendicularly, by its rear-end, from the ceiling; but the suspension-cord has gained considerably in length and consists of the original thread eked out by a sort of ribbon. The grub is at dinner: head downwards, it is digging into the limp belly of one of the caterpillars. I touch up the game that is still intact with a straw. The caterpillars grow restless. The grub forthwith retires from the fray. And how? Marvel is added to marvel: what I took for a flat cord, for a ribbon, at the lower end of the suspension-thread, is a sheath, a scabbard, a sort of ascending gallery wherein the grub crawls backwards and makes its way up. The cast shell of the egg, retaining its cylindrical form and perhaps lengthened by a special operation on the part of the new-born larva, forms this safety-channel. At the least sign of danger in the heap of caterpillars, the larva retreats into its sheath and climbs back to the ceiling, where the swarming rabble cannot reach it. When peace is restored, it slides down its case and returns to table, with its head over the viands and its rear upturned and ready to withdraw in case of need.

Third and last act. Strength and vigour [[26]]have come; the larva is sturdy enough not to dread the movements of the caterpillars’ bodies. Besides, the caterpillars, mortified by fasting and weakened by a prolonged torpor, become more and more incapable of defence. The perils of the tender babe are succeeded by the security of the lusty stripling; and the grub, henceforth scorning its sheathed lift, lets itself drop upon the game that remains. And thus the banquet ends in normal fashion.

That is what I saw in the nests of both species of Eumenes, that is what I showed to friends who were even more surprised than I by these ingenious tactics. The egg hanging from the ceiling, at a distance from the provisions, has naught to fear from the caterpillars, which flounder about below. The newly-hatched worm, whose suspension-cord is lengthened by the sheath of the egg, reaches the game and takes a first cautious bite at it. If there be danger, it climbs back to the ceiling by retreating inside the scabbard. This explains the failure of my earlier attempts. Not knowing of the safety-thread, so slender and so easily broken, I gathered at one time the egg, at another the young larva, after my inroads at the top had caused them to fall into the [[27]]midst of the live provisions. Neither of them was able to thrive when brought into direct contact with the dangerous game.

If any one of my readers, to whom I appealed just now, has thought out something better than the Eumenes’ invention, I beg that he will let me know, for there is a curious parallel to be drawn between the inspirations of reason and those of instinct. [[28]]

[1] I include three species promiscuously under this one name, that is to say, E. pomiformis, Fabr., E. bipunctis, Sauss., and E. dubius, Sauss. As I did not distinguish between them in my first investigations, which date a very long time back, it is not possible for me to-day to attribute to each of them its respective nest. But their habits are the same, for which reason this confusion does not injure the order of ideas in the present chapter.—Author’s Note. [↑]

[2] The Grey Worm is the caterpillar of Noctua segetum, the Dart or Turnip Moth. It is hunted by the Hairy Ammophila, for whom cf. The Hunting Wasps, by J. Henri Fabre, translated by Alexander Teixeira de Mattos: chap. xviii.—Translator’s Note. [↑]

[3] Cf. The Hunting Wasps: passim; Insect Life, by J. H. Fabre, translated by the author of Mademoiselle Mori: chaps. iii. to xii., xiv. to xvii. and xix.; The Life and Love of the Insect, by J. Henri Fabre, translated by Alexander Teixeira de Mattos: chaps. xi. to xii.; and Social Life of the Insect World, by J. H. Fabre, translated by Bernard Miall: chap. xiii.—Translator’s Note. [↑]

[4] Marcus Vitruvius Pollio, the Roman architect and engineer.—Translator’s Note. [↑]

[5] Cf. The Mason-bees, by J. Henri Fabre, translated by Alexander Teixeira de Mattos: chaps. i. to iii. et passim.—Translator’s Note. [↑]

[6] .63 inch to .7 inch.—Translator’s Note. [↑]

[7] .12 inch.—Translator’s Note. [↑]

[8] Also known as the Measuring-worm, the caterpillar of the Geometrid Moth.—Translator’s Note. [↑]

[9] .585 inch.—Translator’s Note. [↑]

[10] .098 inch.—Translator’s Note. [↑]

[11] .27 by .50 inch.—Translator’s Note. [↑]

[12] Cf. Bramble-bees and Others, by J. Henri Fabre, translated by Alexander Teixeira de Mattos: chap. iv.—Translator’s Note. [↑]

[13] Cf. The Hunting Wasps: chaps. iv. to viii. and xiii. to xx.—Translator’s Note. [↑]

[[Contents]]

CHAPTER II

THE ODYNERI

The Eumenes’ suspension-cord and ascending-sheath are rendered necessary by the large number and the incomplete paralysis of the caterpillars provided for the larva; the object of the ingenious system is to avert danger. This, at least, is how I regard the concatenation of causes and effects. But I yield to no one in my distrust of whys and wherefores; I know how slippery our footing becomes when we venture on interpretations; and, before declaring the reasons of any fact observed, I seek for a batch of proofs. If the singular installation of the Eumenes’ egg is really due to the reasons suggested, then, wherever we find similar conditions of danger, namely, a multiplicity of dishes combined with incomplete torpor, we must also find a similar method of protection, or some other method having an equivalent effect. The repetition of the act will bear witness to the correctness of the interpretation; and, if it is not reproduced elsewhere, with such variations [[29]]as may be required, the case of the Eumenes will remain a very curious instance, without acquiring the far-reaching significance which I suspect it of bearing. Let us generalize, the better to establish the facts.

Now not far removed from the Eumenes are the Odyneri, the Solitary Wasps observed by Réaumur.[1] They have the same costumes, the same wings folded lengthwise, the same predatory instincts and, above all, as the supreme condition, the same accumulations of prey retaining sufficient power of movement to be dangerous. If my arguments are well-founded, if I am right in my conjectures, the egg of the Odynerus should be slung from the ceiling of the cell like the egg of the Eumenes. My conviction, based upon logic, is so positive that I already seem to see this egg, recently laid, quivering at the end of the life-line.

Ah, I confess that it needed a robust faith to cherish the audacious hope of discovering anything further when the masters had seen nothing! I read and reread Réaumur’s essay on the Solitary Wasp. [[30]]The Insect’s Herodotus gives us a host of particulars, but says nothing, absolutely nothing, about the hanging egg. I consult Léon Dufour,[2] who treats subjects of this kind with his usual raciness: he has seen the egg; he describes it; but of the suspension-thread not a word. I consult Lepeletier,[3] Audouin,[4] Blanchard:[5] they are absolutely silent on the means of protection which I expect to find. Is it possible that a detail of such great importance can have escaped all these observers? Am I the dupe of my imagination? Is the protective system, though proved to my mind by close logical reasoning, merely one of my [[31]]dreams? Either the Eumenes have lied to me or my hopes are justified. As a disciple rebelling against his masters, a disciple strong in arguments which I believed invincible, I set to work investigating, convinced that I should succeed. And I did succeed; I found what I was looking for; I found something better still. Let me set things down in detail.

There are various Odyneri established in my neighbourhood. I know one who takes possession of the abandoned nests of Eumenes Amadei. This nest, a structure of unusual solidity, is not a ruin when its owner moves away; it loses only its neck. The cupola, preserved untouched, is a fortified retreat of too convenient a nature to remain vacant. Some Spider adopts the cavern, after lining it with silk; Osmiæ[6] take refuge in it in rainy weather, or else make it their dormitory, wherein to spend the night; an Odynerus divides it, by means of clay partitions, into three or four chambers, which become the cradles of as many larvæ. A second species uses the deserted nests of the Pelopæus;[7] a third, removing the pith from [[32]]a dry bramble-stem, obtains, for the use of her family, a long sheath, which she subdivides into stories; a fourth bores a gallery in the dead wood of some fig-tree; a fifth digs herself a shaft in the soil of a footpath and surmounts it with a cylindrical, vertical kerb. All these industries are worth studying, but I should have preferred to discover that which Réaumur and Dufour have rendered famous.

On a steep bank of red clay, I at length recognize, in no great profusion, the signs of a village of Odyneri. Here are the characteristic chimneys mentioned by the two historians, that is to say, the curved tubes, with their guilloche-work, that hang at the entrance to the dwelling. The bank is exposed to the heat of the noonday sun. A little tumbledown wall surmounts it; behind is a dense screen of pines. The whole forms a warm refuge, such as the Wasp requires for setting up house. Moreover, we are now in the second fortnight of the month of May, which is just the working-season, according to the masters. The outside architecture, the site and the period all agree with what Réaumur and Léon Dufour have told us. Have I really chanced upon one or other of their Odyneri? This remains [[33]]to be seen and without delay. Not one of the ingenious constructors of guilloche porticoes shows herself, not one arrives; I must wait. I take up my position close by, to watch the homing insects.

Ah, how long the hours seem, spent motionless, under a burning sun, at the foot of a declivity which sends the heat of an oven beating down upon you! Bull, my inseparable companion, has retired some distance into the shade, under a clump of evergreen oaks. He has found a layer of sand whose depths still retain some traces of the last shower. He digs himself a bed; and in the cool furrow the sybarite stretches himself flat upon his belly. Lolling his tongue and thrashing the boughs with his tail, he keeps his soft, deep gaze fixed upon me:

“What are you doing over there, you booby, baking in the heat? Come here, under the foliage; see how comfortable I am!”

That is what I seem to read in my companion’s eyes.

“Oh, my Dog, my friend,” I should answer, if you could only understand, “man is tormented by a desire for knowledge, whereas your torments are confined to a desire [[34]]for bones and, from time to time, a desire for your sweetheart! This, notwithstanding our devoted friendship, creates a certain difference between us, even though people nowadays say that we are more or less related, almost cousins. I feel the need to know things and am content to bake in the heat; you feel no such need and retire into the cool shade.”

Yes, the hours drag when you lie waiting for an insect that does not come. In the pinewood hard by, a couple of Hoopoes are chasing each other with the amorous provocations of spring:

“Oopoopoo!” cries the cock, in a muffled tone. “Oopoopoo!”

Latin antiquity called the Hoopoe Upupa; Greek antiquity named it Ἔποψ. But Pliny turned the ἔ into ou and must have pronounced the word Oupoupa, as the cry imitated by the name teaches me to do. Rarely have I received a lesson in Latin pronunciation better authenticated than yours,[8] you beautiful bird, who provide a diversion for my long hours of weariness. Faithful to your idiom, you say “Oopoopoo!” as you said in the days of [[35]]Aristotle and Pliny, as you said when your note sounded for the first time. But our own idioms, our primitive idioms, what has become of them? The scholar cannot even recover their traces. Man alters; animals do not change.

At last, here we are at last! See, the Odynerus arrives, with a flight as silent as the Eumenes’. She disappears into the curved cylinder of the vestibule, bringing home a grub beneath her abdomen. I place a small glass test-tube at the entrance to the nest. When the insect emerges, it will be caught. Done! The Wasp is caught and at once decanted into the asphyxiating-flask, with its strips of paper steeped in bisulphide of carbon. And now, my Dog, still lolling your tongue and frisking your tail, we can be off; the day has not been wasted. We will come back to-morrow.

Upon investigation, my Odynerus does not correspond with what I expected to see. This is not the species of which Réaumur speaks (O. spinipes); nor is it the species studied by Dufour (O. Reaumurii); it is another. (O. reniformis, Latr.), a different one, though addicted to the same arts. Already the naturalist of the Landes had [[36]]allowed himself to be deceived by that similarity in architecture, provisions and habits; he thought that he was observing Réaumur’s Solitary Wasp, whereas in reality his tube-builder presented specific differences.

We know the worker; it remains for us to become acquainted with her work. The entrance to the nest opens in the perpendicular wall of the bank. It is a round hole, on the edge of which is built a curved tube, with the orifice turned downwards. Made with the materials cleared from the burrow under construction, this tubular vestibule is composed of grains of earth, not arranged in continuous courses, but leaving small vacant intervals. It is a species of open-work, a lacework of clay. Its length is about an inch and its internal diameter a fifth of an inch. This portico is continued by the gallery, of the same diameter, which slants into the soil to a depth of nearly six inches. Here this main gallery branches into short corridors, each giving access to a cell which is independent of its neighbours. Each larva has its chamber, which can be reached by a special passage. I have counted as many as ten of them; and there may be more. These chambers have nothing [[37]]remarkable about them, either in construction or in capacity; they are just culs-de-sac ending the corridors that give access to them. Some are horizontal, some more or less sloping; there is no fixed rule. When a cell contains what it is meant to contain, the egg and the provisions, the Odynerus closes the entrance with a little earthen lid; she then digs another near it, on one side of the principal gallery. Lastly, the common road to the cells is blocked with earth; the tube at the entrance is demolished, to furnish material for the work done inside the nest; and every vestige of the habitation disappears.

The surface of the bank is of clay baked in the sun; it is almost brick. I break into it with difficulty, making use of a small pocket-trowel. Underneath, it is much less hard.

How does the frail miner manage to sink a gallery in this brick? She employs, I cannot doubt, the method described by Réaumur. I will therefore reproduce a passage from the master’s writings, to give my younger readers a glimpse into the habits of the Odyneri, habits which my very small colony did not enable me to observe in all their details: [[38]]

“It is at the end of May that these Wasps set to work; and one can see them busily labouring during the whole of June. Though their actual object is only to dig in the sand a hole a few inches deep and not much wider than their bodies, one might suppose that they had another end in view; for, to make this hole, they build on the outside a hollow tube, which has as its base the circumference of the entrance to the hole and which, after following a direction perpendicular to the surface containing that aperture, turns downwards. This tube becomes longer in proportion as the hole becomes deeper; it is built of the sand drawn from the hole; it is fashioned in coarse filigree, or a sort of guilloche. It is made of big, granular, winding fillets, which do not touch at all points. The gaps left in between make it look as if it were artistically constructed, whereas it is only a sort of scaffolding by means of which the mother’s tactics are rendered swifter and surer.

“Though I knew these insects’ two teeth to be capital instruments, capable of breaking into very hard substances, the task which they had to perform appeared to me rather severe for them. The sand on which they had to act was scarcely less hard than ordinary [[39]]stone; at least, one’s finger-nails made but a poor impression upon its outer layer, which the sun’s rays had dried more thoroughly than the rest. But, when I succeeded in observing these workers at the moment when they were beginning to bore a hole, they taught me that they did not need to subject their teeth to so harsh an ordeal.

“I saw that the Wasp begins by softening the sand which she proposes to remove. Her mouth discharges upon it a drop or two of water, which is promptly swallowed by the sand, turning it instantly into a soft paste which her teeth scrape and remove without difficulty. Two of her legs, the foremost pair, immediately proceed to gather it into a little pellet, about the size of a currant-seed. It is with this pellet, the first one removed, that the Wasp lays the foundations of the tube which we have described. She carries her pellet of mortar to the edge of the hole which she has just made by removing it; her teeth and feet turn it about, flatten it and make it stand up higher than it did before. This done, the Wasp again sets about removing sand and loads herself with another pellet of mortar. Soon she contrives to have extracted enough [[40]]sand to make the entrance of the hole perceptible and to have laid the foundation of the tube.

“But the work can proceed quickly only so long as the Wasp is able to moisten the sand. She is obliged to take trouble to renew her store of water. I do not know whether she simply went to take in water at some stream, or whether she drew, from some plant or fruit, a more sticky fluid; what I do know is that she returned without delay and set to work with renewed zeal. I observed one Wasp who managed, in about an hour, to sink a hole the length of her body and who raised a chimney as tall as the hole was deep. At the end of a few hours the tube stood two inches high and she was still deepening the hole that lay underneath.

“It did not appear to me that she had any rule respecting the depth which she gives it. I have found some whose hole ran more than four inches from the orifice; others whose hole measured only two or three inches. Again, over one hole you will find a tube twice or three times as long as that over another. Not all the mortar removed from the hole is invariably employed to prolong it. In cases where the [[41]]Wasp has given the tube a length which she considers sufficient, you see her simply arrive at the opening to the tube, put her head beyond its edge and forthwith drop her pellet, which falls to the ground. In this way I have often observed a quantity of rubbish at the foot of certain holes.

“The object for which the hole is pierced in a solid mass of mortar or sand cannot appear in doubt: it is plainly intended to receive an egg, together with a store of foodstuffs. But we do not so easily see to what end the mother has built the mortar shaft. By continuing to follow her labours, we shall discover that it means to her what a stack of well-laid stones means to the masons building a wall. Not the whole of the tunnel which she has excavated is intended as a lodging for the larva which will be born inside; a portion will be quite enough. Yet it was necessary that the hole should be dug to a certain depth, in order that the larva may not find itself exposed to too great a heat when the sun’s rays fall on the outer layer of sand. It will occupy only the end of the tunnel. The mother knows what space she must leave vacant and this space she retains; but she fills up all the remainder and replaces in the upper [[42]]portion of the hole as much of the sand removed from it as is necessary to stop it up. It is to have this mortar within reach that she has built that shaft. Once the egg is laid and the store of victuals placed within its reach, we see the mother come and gnaw the end of the shaft, after first moistening it, carry the pellet inside and next return for more, in the same manner, until the hole is blocked right up to the opening.”

Réaumur goes on to speak of the victuals heaped up in the cells, the “green grubs[9],” as he calls them, heedless of the ugly alliteration. Not having seen the same things, because my Odynerus is of a different species, I will continue my story. I counted the head of game in three cells only: the colony was a small one; I had to deal tenderly with it if I would follow its history to the end. In one of the cells, before the provisions were broached, I counted twenty-four pieces; in each of the two others, which were likewise intact, I counted twenty-two. Réaumur found only eight to twelve pieces in the larder of his Odynerus; and Dufour, [[43]]in the store-room of his, discovered a batch of ten to twelve. Mine requires twice as many, a couple of dozen, which may be due to the smaller size of the game. No predatory Wasp of my acquaintance, apart from the Bembeces,[10] who obtain their supplies from day to day, approaches this prodigality in numbers. Two dozen grub-worms to make a meal for only one! How far removed are we from the single caterpillar of the Hairy Ammophila! And what delicate precautions must be taken for the safety of the egg in the midst of such a crowd! A scrupulous vigilance is necessary here, if we would obtain a true conception of the dangers to which the Odynerus’ egg is exposed and of the means that save it from danger.

And, in the first place, what variety of game is this? It consists of worms as thick as a knitting-needle and varying slightly in length. The biggest measure a centimetre.[11] The head is small, of an intense, glossy black. The segments, unlike those of the caterpillars, have no legs, either true or false, but all, without exception, are furnished with ambulatory organs in the [[44]]shape of a pair of small fleshy nipples. These worms, though of the same species, to judge by their general characteristics, differ in colouring. They are a pale, yellowish green, with two wide longitudinal stripes of pale pink in some and of a more or less deep green in others. Between these two stripes, on the back, runs a streak of pale yellow. The whole body is sprinkled with little black tubercles, each bearing a hair on its crest. The absence of legs proves that they are not caterpillars, not the larvæ of Butterflies or Moths. According to Audouin’s experiments, Réaumur’s “green grubs” are the larvæ of a Weevil, Phytonomus variabilis, an inhabitant of the lucerne-fields. Can my worms, pink or green, also belong to some little Weevil? It is quite possible.

Réaumur described the grubs composing the victuals of his Odynerus as alive; he tried to rear some, hoping to see a Fly or a Beetle appear from them. Léon Dufour, on his side, called them live caterpillars. The mobility of the game provided escaped neither of the two observers; they had before their eyes grubs that moved about and gave full signs of life.

What they saw I also see. My little [[45]]larvæ frisk and fidget; curled at first in the shape of a ring, they uncurl themselves and curl again, if I do no more than slowly turn the small glass tube in which I have imprisoned them. When touched with the point of a needle, they struggle abruptly. Some succeed in shifting their position. While engaged in rearing the Odynerus’ egg, I opened the cell lengthwise, so as to reduce it to a semicylinder; in the little trench thus made, which was kept horizontal, I placed a few head of game. Next day usually I found that one of them had fallen out, a proof of movement, of a change of position, even when nothing was disturbing its repose.

These larvæ, I am firmly convinced, have been wounded by the Odynerus’ sting, for she would not carry a rapier merely for show. Possessing a weapon, she employs it. However, the wound is so slight that Réaumur and Léon Dufour did not suspect its existence. To their mind the prey was alive; to mine it is very nearly alive. In these conditions we can see to what perils the Odynerus’ egg would be exposed but for exquisitely prudent precautions. There they are, those restless grubs, to the number of two dozen in one cell, side by side with [[46]]the egg, which a mere nothing is enough to endanger. By what means will this very delicate germ escape the perils of the crowd?

As I foresaw by my process of reasoning, the egg is slung from the ceiling of the cell. A very short thread fastens it to the top wall and lets it hang free in space. The first time that I saw this egg, quivering at the end of its thread at the least jerk and confirming by its oscillations the correctness of my theoretical views, I experienced one of those moments of inward joy which atone for much vexation and weariness. I was to have many more such moments, as will be seen. If we pursue our investigations in the insect world with loving patience and a practised eye, we always find some marvel in store for us. The egg, I was saying, swings from the ceiling, held by a very short and extremely fine thread. The cell is sometimes horizontal, sometimes slanting. In the first case, the egg hangs perpendicularly to the axis of the cell and its lower end approaches to within a twelfth of an inch of the opposite wall; in the second case, the vertical direction of the egg forms a more or less acute angle with that axis.

I wished to follow the progress of this [[47]]hanging egg at my leisure, with the greater convenience of observation which is possible at home. With the egg of Eumenes Amadei this was all but impracticable, because of the cell, which could not be moved together with the block that most often serves as its foundation. A house of this kind demands observation on the spot. The Odynerus’ dwelling does not present the same drawback. When a cell is laid bare and found to be in the condition which I desire, I dig round it with the point of a knife until I detach a cylinder of earth containing the cell, which is reduced to an open trough, so as to conceal nothing of what is to happen inside. The victuals are extracted piecemeal, with every care, and decanted separately into a glass tube. I shall thus avoid the accidents that might be occasioned by the swarming heap of grubs during the inevitable shaking of the journey. The egg alone remains, swinging in the empty enclosure. A large tube receives the cylinder of earth, which is wedged in position with pads of cotton-wool. I place my booty in a tin box and carry it in my hand in such a position that the egg hangs vertically without striking against the walls of the cell. [[48]]

Never have I effected a removal which called for such nice precautions. An accidental movement might easily break the suspension-thread, which is so delicate that it needs the magnifying-glass to distinguish it; excessive oscillation might bruise the egg against the walls of the cell: I had to beware of turning it into a sort of bell-clapper dashing against its bronze prison. I walked, therefore, with the stiffness of an automaton, all of one piece, with steps methodically calculated. What a misfortune should some acquaintance appear and make me stop a moment, for a chat or a shake of the hand: the least distraction on my part would perhaps ruin my schemes! Still more embarrassing would it be should Bull, who cannot endure a black look, find himself muzzle to muzzle with a rival and try to get quits with him by flying at his throat. I should have to put an end to the fray, to avoid the scandal of a well-brought-up Dog showing intolerance of the village cur. The squabble would end in the breakdown of all my experimental scaffolding. And to think that the eager preoccupations of a person not entirely devoid of sense may sometimes be dependent on a Dog-fight! [[49]]

Lord be praised, the road is deserted! The journey is accomplished without hindrance; the thread, my great anxiety, does not break; the egg is not bruised; everything is in order. The little clod of earth is put in a place of safety, with the cell in a horizontal position. I distribute near the egg two or three of the grubs which I have collected; the complete allowance of provisions would cause trouble, now that the cell possesses only half its enclosing wall and is reduced to a semicylinder. Two days later, I find the egg hatched. The young larva, yellow in colour, is hanging by its hinder end, head downwards. It is busy with its first grub, whose skin is already growing limp. The suspension-cord consists of the short thread that supported the egg, with the addition of the slough, now reduced to a sort of crumpled ribbon. In order to remain sheathed in the end of this hollow ribbon, the hinder end of the new-born larva is at first slightly constricted and then swells into a button. If I disturb it while at rest, or if the victuals move, the larva withdraws, shrinking back upon itself, but without retreating into the ascending-sheath, as does the Eumenes’ larva. The tethering-cord does not serve as a scabbard, [[50]]as a refuge into which the larva can retire; it is rather an anchor-chain, which gives it a purchase on the ceiling and enables it to protect itself by shrinking to a safe distance from the heap of victuals. When things are quiet, the larva lengthens out and returns to its grub. Thus do matters happen at the start, according to my observations, of which some were made at home, in my rearing-jars, and others on the spot, when I unearthed cells containing a larva young enough for my purpose.

The first grub is devoured in twenty-four hours. The larva thereupon, so it seemed, goes through a moult. For at least some time it remains inactive and contracted; then it releases itself from the cord. It is now free, in contact with the heap of grubs and henceforth unable to step out of the way. The life-line has not lasted long; it protected the egg and safeguarded its hatching; but the larva is still very weak and the peril has not diminished. This means that we shall discover other means of protection.

By a very strange exception, whereof so far I know no other instance, the egg is laid before the provisions are stored. I have seen cells which as yet contained absolutely nothing in the way of victuals and which [[51]]nevertheless had the egg swinging from the ceiling. I have seen others, also furnished with the egg and so far containing only two or three head of game, a first instalment of the abundant dish of twenty-four. This early egg-laying, so utterly unlike what happens in the case of the other predatory Wasps, has its underlying motive, as we shall see; it has its logic at which we cannot fail to marvel.

The egg, laid in the empty cell, is not fixed at random on the first spot that offers upon the enclosing wall, which is vacant at all sides; it is hung near the far end, opposite the entrance. Réaumur had already noted this position of the budding larva, but without insisting on a detail whose importance he did not suspect:

“The grub,” he says, “is born at the bottom of the hole, that is, at the back of the cell.”

He does not speak of the egg, which he does not appear to have seen. This position of the grub was so well known to him that, wishing to attempt the rearing of a grub in a glass cell made with his own hands, he placed the larva at the bottom and the victuals on top of it. [[52]]

Why do I linger over a petty detail which the famous historian of the Odyneri tells in half-a-dozen words? A petty detail? It is nothing of the kind; on the contrary, it is a circumstance of paramount importance. And this is why: the egg is laid at the back, necessitating an empty cell which will be victualled after the egg is laid. The provisions are now stored, piece by piece, layer upon layer, in front of the egg; the cell is crammed with game right up to the entrance, which in the end is sealed.

Of all these pieces, the obtaining of which may take several days, which are the earliest in point of date? Those nearest the egg. Which are the latest? Those by the entrance. Now it is obvious—besides, it may be proved, if necessary, by direct observation—it is obvious, I say, that the heaped worms lose strength from day to day. The effects of a prolonged fast would be enough to produce this result, to say nothing of the disorders due to a wound which becomes worse as time goes on. The larva born at the back of the cell has therefore beside it, in its first youth, the less dangerous provisions, the oldest in date and consequently the feeblest. As it works its way through the heap, it finds more recent [[53]]game, which is also more vigorous; but this is attacked without danger, because the larva’s own strength has come.

This progress from the more to the less nearly mortified victims presumes that the grubs do not disturb the order in which they have been stacked. That in fact is what happens. Former historians of the Odyneri have all remarked that the grubs provided for the larva are curled in the shape of a ring:

“The cell,” says Réaumur, “was occupied by green rings, to the number of eight or twelve. Each of these rings consisted of a vermiform larva, alive, curled up and with its back fitting exactly against the wall of the hole. These grubs, laid in this way one on top of the other and even pressed together, had no liberty of movement.”

I, in my turn, remark similar facts in my two dozen grub-worms. They are curled in a ring; they are stacked one upon another, but with a certain confusion in the ranks; their backs touch the wall. I will not attribute this circular curve to the effect of the sting which was very probably administered, for I have never observed it in [[54]]the caterpillars stabbed by the Ammophilæ; I believe rather that the position is natural to the grub during inaction, even as it is natural for the Iuli[12] to coil themselves into a spiral. In this living bracelet there is a tendency to return to the rectilinear conformation; it is a bent bow fighting against the obstacle that surrounds it. By the very fact, therefore, of being curled up, each grub keeps more or less steady by pressing its back a little against the wall; and it retains its place even when the cell approaches the vertical.

Moreover, the shape of the cell has been calculated with a view to this manner of storing. In the part next the entrance, the part which one might call the store-room, the cell is cylindrical and narrow, so as to afford the living rings as little space as possible; they are thus kept in position and are unable to slip. It is here that the grubs are stacked, squeezed one against the other. At the other end, near the back, the cell expands into an ovoid to give the larva elbow-room. The differences between the two diameters is very perceptible. At the entrance I find only four millimetres:[13] at [[55]]the back I find six.[14] Thanks to this inequality of width, the cell comprises two apartments: the provision-store in front and the dining-room behind. The Eumenes’ spacious cupola does not permit of this arrangement; there the game is heaped up in disorder, the oldest in date promiscuously with the most recent; and each piece is merely bent, not rolled. The ascending-sheath provides a remedy for the disadvantages of this confusion.

Note also that the packing of the victuals is not the same from one end of the Odynerus’ skewerful to the other. In the cells whose provisions have not yet or have only recently been broached, I observe this detail: near the egg or the newly-hatched larva, in the part which I have just described as the dining-room, the space is not fully occupied; there are just a few grubs here, three or four, somewhat isolated from the bulk and leaving enough room to ensure the safety of either the egg or the young larva. This is the food supplied for the early meals. If there be danger in the first mouthfuls, which are the most risky of all, the life-line provides a means of withdrawal. More towards the front, the game [[56]]is piled in close-packed layers, the stack of worms is continuous.

Will the larva, now that it possesses a modicum of strength, force itself imprudently into this heap? Far from it. The victuals are consumed in due order, from the bottommost to the topmost. The larva drags towards it, to a little distance, into the dining-room, the first ring that offers, devours it without danger of being inconvenienced by the others and thus, layer by layer, consumes the batch of two dozen, always in complete security.

Let us retrace our steps and end with a brief summary. The large number of grubs provided for a single cell and their very incomplete paralysis jeopardize the security of the Wasp’s egg and of her new-born larva. How is the danger to be averted? This is the problem; and it has several solutions. The Eumenes, with her sheath, which enables the larva to climb back to the ceiling, gives us one; the Odynerus, in her turn, gives us hers, a solution no less ingenious and much more complicated.

The egg and also the newly-hatched larva have to be saved from the danger of contact with the game. A suspension-thread solves [[57]]the difficulty. Up to this point, that is the method adopted by the Eumenes; but soon the young larva, having eaten its first grub, drops off the thread that gave it a support whereby to shrink out of harm’s way. A sequence of conditions now begins, all directed towards its welfare.

Prudence demands that the very young larva shall first attack the most inoffensive of the grubs, that is those most nearly deadened by abstinence, in short, the grubs first placed in the cell; it demands, moreover, that the consumption of these grubs shall proceed from the oldest specimens to the most recent, so that the larva may have fresh game to the end. With this object, a curious exception is made to the general rule: the egg is laid before the victualling is commenced. It is laid at the back of the cell; in this way, the stacked provisions will present themselves to the larva in due order of date.

That is not enough: it is important that the grubs shall be unable, in moving, to alter their respective positions. This circumstance is provided for: the store-room is a narrow cylinder in which change of place is difficult.

Even that is not sufficient: the larva must [[58]]have room enough to move about at ease. The condition is fulfilled: at the back, the cell forms a comparatively spacious dining-room:

Is that all? Not yet. The dining-room must not be encumbered like the rest of the cell. The matter has been seen to: the first course consists of a small number of specimens.

Have we done? By no means. It is not of any use to have a narrow cylinder for the larder: if the grubs straighten out, they will slip lengthwise and disturb the nurseling in the back-room. This has been remedied: the game selected is a larva which deliberately rolls itself into a bracelet and maintains its position by its own tendency to unbend.

It is by the ingenious removal of this series of difficulties that the Odynerus succeeds in leaving a family. We have seen enough of her exquisite foresight to amaze us. What would it be were nothing to remain concealed from our dull eyes!

Can the insect have acquired its skill gradually, from generation to generation, by a long series of casual experiments, of blind gropings? Can such order be born of chaos; such foresight of hazard; such [[59]]wisdom of stupidity? Is the world subject to the fatalities of evolution, from the first albuminous atom which coagulated into a cell, or is it ruled by an Intelligence? The more I see and the more I observe, the more does this Intelligence shine behind the mystery of things. I know that I shall not fail to be treated as an abominable “final causer.” Little do I care! A sure sign of being right in the future is to be out of fashion in the present. [[60]]

[1] René Antoine Ferchault de Réaumur (1683–1757), inventor of the Réaumur thermometer and author of Mémoires pour servir à l’histoire naturelle des insectes.—Translator’s Note. [↑]

[2] Jean Marie Léon Dufour (1780–1865), an army surgeon who served with distinction in several campaigns and afterwards practised as a doctor in the Landes, where he attained great eminence as a naturalist. Fabre often refers to him as the Wizard of the Landes. Cf. The Life of the Spider, by J. Henri Fabre, translated by Alexander Teixeira de Mattos: chap. i; and The Life of the Fly by J. Henri Fabre, translated by Alexander Teixeira de Mattos: chap. i.—Translator’s Note. [↑]

[3] Amédée Comte Lepeletier de Saint-Fargeau (1769–circa 1850), author of an Histoire naturelle des insectes (1836–1846) and of the volume on insects in the Encyclopédie méthodique. He was a younger brother of Louis Michel and Félix Lepeletier de Saint-Fargeau, the members of the Convention.—Translator’s Note. [↑]

[4] Jean Victor Audouin (1797–1841), founder of the Annales des sciences naturelles and author of a number of works on insects injurious to agriculture.—Translator’s Note. [↑]

[5] Émile Blanchard (b. 1820), author of various works on insects, Spiders, etc.—Translator’s Note. [↑]

[6] Cf. Bramble-bees and Others: chaps. i. to vii.—Translator’s Note. [↑]

[7] Cf. Chapter III. of the present volume.—Translator’s Note. [↑]

[8] The French, it may hardly be necessary to explain, pronounce Latin precisely as though it were French.—Translator’s Note. [↑]

[9] Réaumur’s actual words are “vers verts;” and Fabre rightly complains of “the hideous assonance.”—Translator’s Note. [↑]

[10] For the Bembex cf. The Hunting Wasps: chaps. xiv. to xvi.—Translator’s Note. [↑]

[11] .39 inch.—Translator’s Note. [↑]

[12] The Iulus belongs to the Myriapod family, which includes the Centipedes, etc.—Translator’s Note. [↑]

[13] .156 inch.—Translator’s Note. [↑]

[14] .234 inch.—Translator’s Note. [↑]

[[Contents]]

CHAPTER III

THE PELOPÆUS

Of the several insects that elect to make their home in our houses, certainly the most interesting, for the beauty of its shape, the singularity of its manners and the structure of its nests, is the Pelopæus, a Wasp hardly known even to the people whose fireside she frequents. Her solitary habits and her peaceful occupation of the premises explain why history is silent in her regard. She is so extremely retiring that her host is nearly always ignorant of her presence. Fame is for the noisy, the importunate, the noxious. Let us try to rescue the modest creature from oblivion. An extremely chilly mortal, the Pelopæus pitches her tent under the kindly sun which ripens the olive and prompts the Cicada’s song; and even then she needs for her family the additional warmth furnished by our dwellings. Her usual refuge is the peasant’s lonely cottage, with its old fig-tree shading the well in front of the door. She [[61]]chooses one exposed to all the heat of summer and, if possible, boasting a capacious fireplace in which a fire of sticks is frequently renewed. The cheerful blaze on winter evenings, when the sacred yule-log burns upon the hearth, is largely responsible for her choice, for the insect knows by the blackness of the chimney that the spot is a likely one. A chimney that is not well glazed by smoke does not inspire her with confidence: people must shiver with cold in that house.

During the dog-days in July and August, the visitor suddenly appears, seeking a place for her nest. She is in no wise disturbed by the bustle and movement of the household: they take no notice of her nor she of them. Spasmodically she examines, now with her sharp eyes, now with her sensitive antennæ, the corners of the blackened ceiling, the angles of the rafters, the chimneypiece, the sides of the fireplace in particular and even the interior of the flue. Having finished her inspection and duly approved of the site, she flies away, soon to return with the little pellet of mud which will form the first layer of the edifice.

The spot which she adopts varies greatly; often it is an extremely curious one, the one [[62]]positive condition being that the temperature should be mild and equable. A furnace heat appears to suit the Pelopæus’ larvæ; at least, the favourite place is the chimney, on either side of the flue, up to a height of twenty inches or so. This snug shelter has its drawbacks. The smoke gets to the nests, especially during the winter, when fires are going all day, and gives them a glaze of brown or black similar to that which covers the stonework. They are so like it in appearance that they might well be taken for inequalities in the mortar which have been overlooked by the trowel. This swarthy distempering is not a serious matter, provided that the flames do not lick against the cluster of cells. That would ensure the destruction of the larvæ, stewed to death in their clay pots. But this danger appears to be foreseen; and the Pelopæus entrusts her family only to chimneys which are too wide for anything but smoke to reach their sides; she is suspicious of the narrow ones which allow the flames to fill the whole entrance to the flue.

In spite of her caution, one peril remains. While the nest is building, at a moment when the Wasp, urged by the need for laying her eggs, cannot bring herself to cease [[63]]working, it sometimes happens that the approach to the dwelling is barred to her for a time, or even for the whole day, either by a curtain of steam rising from a stew-pan or by clouds of smoke resulting from damp firewood. Washing-days are the most risky. From morning to night, the housewife keeps the huge cauldron boiling with all the odds and ends of the wood-shed: chips, bits of bark, leaves, fuel that burns with difficulty and intermittently. The smoke from the hearth, the steam from the cauldron and the reek from the wash-tub form in front of the fireplace a dense mist with very few rifts in it. I have at rare intervals surprised the Pelopæus in the presence of some such obstacle.

It is told of the Water-ouzel, the Dipper, that, to get back to his nest, he will fly through the cataract under a mill-weir. The Pelopæus is even more daring: with her pellet of mud in her teeth, she crosses the cloud of smoke and disappears behind it, henceforth invisible, so thick is the screen. A spasmodic chirring, her working-song, alone betrays the mason at her task. The building rises mysteriously behind the cloud. The ditty ceases and the Wasp emerges from the steam-flakes, fit [[64]]and well, as though coming out of a limpid atmosphere. She has faced the fire, like the fabled Salamander, and she will face it all day, until the cell is built, crammed with victuals and closed.

Cases of this kind occur too seldom to satisfy fully the curiosity of a seasoned observer. I should have liked to arrange the mist-screen myself and thus to try a few experiments bearing upon the dangerous crossing; but I was a stranger, a spectator by sheer chance; and all that I could do was to trust to luck, without interfering with the washing-operations and perhaps upsetting them. What a sorry idea the housewife engaged on that grave business would have had of my intelligence if I had ventured to touch her fire in order to worry a Wasp!

“I’a pétan cièucle: little things please little minds,” she would have been sure to think.

In the eyes of the peasant, to occupy one’s self with such small fry is a lunatic’s game, the amusement of a cracked mind.

Once and once only fortune smiled upon me; but I was not ready to profit by it. The thing took place at my own house, by my own fireside and, as it happened, on a washing-day. I had not long been appointed [[65]]to the Avignon grammar-school. It was close upon two o’clock; and in a few minutes the roll of the drum would summon me to display the properties of the Leyden jar to an audience of wool-gatherers. I was preparing to start, when I saw a strange, agile insect, with a slender body and a gourd-shaped abdomen slung at the end of a long thread, dart through the reek rising from the wash-tub. It was the Pelopæus, whom I saw for the first time with observant eyes. A novice still and anxious to become better-acquainted with my visitor, I fervently commended the insect to the watchful care of the household, begging them not to disturb it in my absence and to manage the fire in such a way as not to inconvenience it in its plucky work of building the walls of its nest right beside the flame. My wishes were carried out religiously.

Things went better than I dared hope. On my return, the Pelopæus was continuing her mason’s work behind the steam of the wash-tub, which stood under the mantel of a wide chimney. Eager as I was to witness the construction of the cells, to identify the nature of the provisions, to follow the evolution of the larvæ, all of them [[66]]biological details entirely new to me, I took good care not to raise the experimental obstacles which I should not fail to set in the path of instinct to-day: a good nest was the sole object that I coveted. Therefore, so far from creating fresh difficulties for the Pelopæus, I did my utmost to reduce those which she had to overcome. I raked the fire, making it much smaller, so as to decrease the volume of smoke in the Wasp’s building-yard; and for a good two hours I watched her diving through the cloud. Next day, the usual niggardly fire was burning intermittently; and there was nothing now to hamper the Pelopæus, who continued her work for some days and without further impediment completed the well-filled nest which was the object of my wishes.

Never again, in the forty years that followed, was my fireplace honoured with such a visit; and it was only by having recourse to the more fortunate hearths of my neighbours that I was able to glean my little bit of information. Nor was it until much later that, profiting by long experience, I had the idea of turning to account the predilection of so many Bees and Wasps for their birthplace and for founding a [[67]]family in the neighbourhood of the nest where they receive perhaps the strongest of all impressions, the first dawn of light. I took Pelopæus-nests which I had collected more or less everywhere during the winter and fixed them in different places, in my present house, which, judging by the sum total of my observations, I considered suitable, notably at the entrance to the chimney both of the kitchen and of the study. I put some in the embrasures of the windows, keeping the outside shutters closed to obtain the requisite sultriness; I stuck some to the dimly-lighted corners of the ceilings. It was in these sites of my choosing that the new generation was to hatch when summer came; it was here that it would settle: at least I thought so. Then I could have conducted in my own way the experiments which I had in mind.

My attempts invariably failed. Not one of my charges returned to the native nest; the less fickle of them contented themselves with brief visits, soon followed by a departure for good. The Pelopæus, it appears, is of a solitary and vagrant disposition: save in exceptionally favourable circumstances, she builds a lonely nest and is quite ready to change her locality from [[68]]generation to generation. As a matter of fact, though this Wasp is fairly common in my village, her dwellings are nearly always scattered one by one, with no traces of any old nests near by. The place of her birth leaves no lasting recollection in the nomad’s memory; and none comes to build beside the ruins of the maternal home.

For that matter, my want of success might well be due to another cause. The Pelopæus certainly is not rare in our southern towns; nevertheless she prefers the peasant’s smoky house to the townsman’s white villa. Nowhere have I seen her so plentiful as in my village, with its tumbledown cottages guiltless of rough-cast and burnt yellow by the sun. My hermitage is not quite so rustic as that: it is a little neater and cleaner; and there is nothing to show that my visitors did not forsake my kitchen and my study, both too sumptuous in their opinion, to go and settle somewhere near in lodgings more to their taste. And so the eagerly desired colonists, who were to have peopled my workroom crammed with books, plants, fossils and entomological cemeteries, took their departure, scorning all that scientific luxury; they went away in search of some [[69]]dim chamber with a solitary window sporting a sprig of wall-flower in an old, cracked stew-pot. Felicities like that are reserved for the humble; and I am therefore reduced to what I have gained by an occasional piece of good luck, irrespective of any efforts of mine. The little that I have seen, in one direction and another, is after all sufficient evidence of the pluck of the Pelopæus, who, to reach her nest built in a corner of the hearth, at times passes through a cloud of steam and smoke. Would she dare to cross a thin sheet of flame? That was what I had proposed to see, if my attempts to acclimatize her in my home had met with any success.

It is obvious that, in displaying a marked predilection for the chimney as her abode, the Pelopæus is not seeking her own comfort: the site chosen means work and dangerous work. She seeks the welfare of her family. This family then, in order to prosper, must require a high temperature, such as is not demanded by the other Wasps or Bees, the Chalicodoma and the Osmia, for instance, who find sufficient shelter under a mortar dome or in the hollow of an exposed reed. Let us see what temperature the Pelopæus finds to her liking. [[70]]

On the side-wall, under the chimneypiece, I hung a thermometer over a Pelopæus-nest. During an hour’s observation, with a fire giving out a moderate heat, it fluctuated between 95° and 105° F. This temperature, it is true, does not remain the same during the long larval period; on the contrary, it varies greatly, according to the season of the year and the time of day. I wanted something better and I found it on two occasions.

My first observation was made in the engine-room of a silk-factory. The back of the boiler reached nearly to the ceiling, the space between being barely twenty inches. It was against this ceiling, right above the huge cauldron, which was always full of water and steam at a high temperature, that the Pelopæus-nest was fixed. At this spot the thermometer marked 120°. This degree of heat was maintained all through the year; it was only at night and on holidays that it decreased.

A country distillery furnished me with the second subject of observation. It combined two excellent conditions for attracting Pelopæi: rural quiet and the heat of a furnace. The nests therefore were numerous, fixed more or less everywhere on [[71]]anything that came to hand, even down to the pile of account-books in which the excisemen registered their troublesome inspections of the proof-spirit. One of these, situated quite close to the still, was tested with the thermometer. It measured 113° of heat.

These few data prove that the larvæ of the Pelopæus are comfortable in a temperature of a hundred degrees or over, a temperature not accidental, like that produced by a fire blazing in a chimney, but constant, such as obtained by a boiler or a still. Tropical heat is favourable to the grub slumbering for ten months in its mud hole. Any seed, in order to sprout, needs a certain quantum of heat, greater or smaller according to its kind. The larva, a sort of animal seed out of which the perfect insect will come by a process of germination even more wonderful than that which turns an acorn into an oak, the larva also claims its quantum of heat. The larva of the Pelopæus can cheerfully endure a temperature that makes the baobab or the oily palm-tree sprout. What then is the origin of this chilly tribe?

A good fire on the hearth, a boiler or a furnace shedding an artificial tropical [[72]]climate around them are useful windfalls, which, however, cannot be relied upon; and the Pelopæus settles in any lodging where she finds warmth and not too garish a light. The corners of a conservatory; a kitchen-ceiling; the embrasure of a window with closed casement and shutters, provided that these furnish some exit-hole; the rafters of a loft, where the warmth of the daily quota of sunshine is preserved by the heaped-up hay and straw; the walls of a cottage bedroom: any of these suit her, so long as the larvæ find a snug shelter in winter. This climatological expert, the daughter of the dog-days, divines the coming peril for her family, that inclement season which she herself will never see.

While she is scrupulous in her choice of a warm spot, on the other hand she is supremely indifferent to the nature of the foundation on which the nest is to be fastened. As a rule, she fixes her groups of cells to the stonework, whether rough-coated or not, and to the timber, whether bare or plastered; but she uses many other supports, some of which are very peculiar. Let us mention a few of these fantastic installations.

My notes speak of a nest constructed inside [[73]]a gourd standing on the mantelpiece of a farm-kitchen. In this narrow-mouthed receptacle the farmer used to keep his shot. As the orifice was always open and the utensil not employed at that time of year, a Pelopæus had found that the peaceful retreat suited her and had gone to the length of building on the layer of small-shot. The gourd had to be broken to extract the bulky edifice.

The same notes tell me of nests built against the pile of account-books in a distillery; in a fur cap relegated to the wall until the return of winter; in the hollow of a brick, back to back with the downy structure of a Cotton-bee; on the sides of a bag of oats; in a piece of lead tubing broken off from an old water-pipe.

I saw something more remarkable still in the kitchen at Roberty, one of the biggest farms near Avignon. It was a large room with a very wide fireplace, in which the soup for the farm-hands and the food for the cattle were simmering in a row of pots and pans. The labourers used to come in from the fields so many at a time, take their seats on benches round the table and devour the portions served to them, with the silent haste that denotes a keen appetite. To enjoy [[74]]this half-hour of comfort, they would take off their hats and smocks and hang them on pegs on the wall. Short though the meal was, it lasted long enough to allow the Pelopæi to inspect the garments and take possession of them. The inside of a straw hat was recognized as a most useful retreat; the folds of a smock were looked upon as a shelter which could be turned to excellent account; and the work of building started forthwith. On rising from table, one of the men would shake his smock, another his hat, to rid it of a heap of mud that was already the size of an acorn.

When the labourers had gone, I had a talk with the cook. She told me of her tribulations: those impudent Bugs were all over the place, dirtying everything with their filth. She was chiefly concerned about the window-curtains. Dabs of mud on the ceiling, on the walls, on the chimneypiece you could put up with; but it was a very different matter when you found them on the linen and the curtains. To keep the curtains clean and dislodge the wretched things who persisted in bringing in their bits of mud, she had to shake them every day, to beat them with a bamboo. And it was all no use: next morning, work was resumed [[75]]with equal vigour on the buildings destroyed the day before.

I sympathized with her sorrows, while greatly regretting that I could not myself take charge of the place. How gladly I would have left the Pelopæi undisturbed, though they covered every scrap of upholstery with mud; how willingly I would have let them have their way, so that I might learn what prospects there are for a nest if perched on the shifting support of a coat or a curtain! The Mason-bee of the Shrubs,[1] heedless of the storm, builds on a twig; but her edifice, constructed of hard mortar, envelops the support, surrounds it on every side and becomes firmly fixed to it. The nest of the Pelopæus is a mere blob of mud, fastened to its support without any special adhesive preparation. It has no hydraulic cement which sets as soon as used, no foundations welded to the supporting base. How can such a method give proper stability? The nests which I find on the coarse canvas of corn-bags come off at the least shake, though the rough mesh of the stuff makes it easier for them to stick on: what will happen when the nests are placed on a piece of fine calico hanging [[76]]perpendicularly and often flicked about, if only by the draught? To build on that strikes me as an aberration of instinct on the part of the architect, who has not yet learnt, in spite of the long lesson of the ages, how perilous are certain sites in human habitations.

Let us leave the constructor and occupy ourselves with the structure. The materials consist exclusively of wet earth, mud or dirt, picked up wherever the soil possesses the proper degree of humidity. When there is a stream in the neighbourhood, the thin clay of the banks is turned to account. But cement-works of this sort are rare or too far off in my stony region; and it is not in such a building-yard that I most frequently witness the gathering of the materials. I can watch the performance at my leisure without leaving my own garden. When a thin trickle of water runs from morning till evening in the little trenches cut in the vegetable-plots, a few Pelopæi, visitors to the neighbouring farms, soon get wind of the glad event. They come hurrying up to take advantage of the precious layer of mud, a rare discovery in this distressing time of drought. One selects a recently-watered furrow, another prefers to [[77]]keep on the bank and settle in a work-yard moistened by capillary action. They scrape and skim the gleaming, slimy surface with their mandibles while standing high on their legs, with wings aquiver and their black abdomen upraised on its yellow pedicel. No neat little housewife, with skirts carefully tucked out of the dirt, could be more adept in tackling a job so prejudicial to the cleanliness of her clothes. These mud-gatherers have not an atom of soil upon them, so careful are they to tuck up their skirts in their fashion, that is to say, to keep their whole body out of the way, all but the tips of their legs and the busy points of their mandibles. In this manner a dab of mud is collected, almost the size of a pea. Taking the load in its teeth, the insect flies off, adds a layer to its building and soon returns to collect another pellet. The same work is pursued as long as the earth remains sufficiently wet, during the hottest hours of the day, for there is always some builder looking about for mortar.

But the most frequented spot is in front of the great fountain in the village. Here there is a large trough where the people round about come to water their Mules. The constant trampling of the heavily-laden [[78]]quadrupeds and the overflow of the water create a perpetual sheet of black mud which neither the heat of July nor the mighty blast of the mistral succeeds in drying. This bed of mire, so unpleasant for the passers-by, is beloved of the Pelopæi, who meet there from every part of the neighbourhood. You seldom pass before the noisome puddle without seeing some of them gathering their pellets amid the hoofs of the Mules slaking their thirst.

The places exploited are enough in themselves to tell us that the mortar is collected ready-made, fit for immediate use without any further preparation than a vigorous kneading which gets rid of the lumps and makes the whole into a homogeneous mass. Other builders in clay, the Mason-bees, for instance, scrape up the dust on the highway and moisten it with saliva to convert it into a plastic material which will harden like stone by virtue of certain chemical properties of the salivary fluid. They set to work like the bricklayer, who mixes his mortar and his plaster by adding water in small quantities. The Pelopæus does not practise this art; the secret of chemical action is denied her; and the mud is employed just as it is picked up. [[79]]

To make sure of this, I stole a few pellets from the busy collectors and, on comparing them with other pellets gathered in the same place and rolled by my own fingers, found no difference between them in appearance or in properties. The result of this comparison is confirmed by an examination of the nest. The structures of the Chalicodomæ are solid masonry, capable of resisting without any protection the prolonged action of rain and snow; those of the Pelopæi are flimsy work, devoid of cohesion and absolutely unfitted to withstand the vicissitudes of the open air. A drop of water laid upon their surface softens the spot touched and reduces it to mud again, while a sprinkling equal to an average shower turns it into pap. They are nothing more than dried slime and become slime again as soon as they are wetted.

The thing is obvious: the Wasp does not improve the mud to make it into mortar; she uses it as it is. It is no less obvious that nests of this sort are not made for out-of-doors, even if the larva were not of such a chilly humour. A shelter that keeps them under cover is indispensable, otherwise they would go to pieces at the first shower of rain. This explains, apart altogether [[80]]from questions of temperature, why the Pelopæus has a preference for human habitations, which afford the best protection against damp. Under the mantels of our chimneys she finds at one and the same time the heat required by the larvæ and the necessary dryness for the nests.

Before receiving its final coating, which conceals the structural details, the Pelopæus’ edifice does not lack elegance. It consists of a cluster of cells, sometimes arranged side by side in one row—which gives the fabric something of the look of a mouth-organ with reeds all short and all alike in size—but more often grouped in a varying number of layers placed one above the other. In the most populous nests I count as many as fifteen cells; others contain only about ten; others again are reduced to three or four, or even to one alone. The first appear to me to represent a mother’s whole output of eggs; the second signify incomplete layings, deposited here and there, perhaps because better sites were found elsewhere.

The cells are not far removed from the cylindrical shape, with a diameter increasing slightly from the mouth to the base. [[81]]They measure three centimetres[2] in length, their breadth where they are widest being about fifteen millimetres.[3] Their delicate surface, carefully polished, shows a series of stringy projections, running obliquely, not altogether unlike the twisted cords of certain kinds of gold-lace. Each of these strings is a layer of the edifice; it comes from the clod of mud employed on the coping of the part already built. By numbering them one can tell how many journeys the Pelopæus has taken to her mortar. I count between fifteen and twenty. For one cell, therefore, the industrious builder fetches materials something like twenty times and perhaps even oftener, for one of these cushions of mud is not always, so it seems to me, completed in a single spell of work.

The main axis of the cells is horizontal, or not far removed from it; the mouth is always turned upwards. And this must needs be so: a pot cannot hold its contents save on condition that it be not upside down. The Pelopæus’ cell is nothing more than a pot destined to receive the preserved foodstuffs, a pile of small Spiders. When laid [[82]]horizontally or slanting a little upwards, the receptacle holds its contents; but with the mouth turned downwards it would lose them. I have lingered a moment over this petty detail to call attention to a curious mistake current in the text-books. Wherever I find a drawing of a Pelopæus-nest, I see it with the orifices of the cells facing downwards. The illustrations go on and on: to-day’s reproduces yesterday’s absurdity. I do not know who was the first to perpetrate this blunder and to think of subjecting the Pelopæus to a task no less arduous than that of the vessel of the Danaides: to fill a pot turned upside down.

Built one by one, stuffed full of Spiders and closed as and when the laying demands it, the cells retain their elegant exterior until the cluster is deemed large enough. Then, to strengthen her work, the Pelopæus covers the whole with a defensive casing; she lays on the plaster with an unsparing trowel, without artistry or any of those delicate and patient finishing-touches which she lavishes upon the work of the cells. The pellet is applied just as it is brought and merely spread with a few careless strokes of the mandibles. Thus the original beauties of the structure—the [[83]]flutings between the cells sat back to back, the corded cushions, the polished stucco—all disappear under a forbidding husk. In this final state, the nest is nothing more than a shapeless protuberance; one would take it for a great splash of mud that had been flung against the wall by accident and dried there.

We find similar methods among the Chalicodomæ. The best mason among them, after she has erected her cells on a pebble, building them in the form of turrets daintily encrusted with bits of gravel, buries her artistic work under a clumsy plaster. Why do they both give this finish and devote such fastidious care to the frontage, when the masterpiece is doomed to disappear, deluged in mortar? We do not build a Louvre and then abandon its colonnades to the unclean trowel. But we must not press the analogy too far. What do insects care about the beauty or ugliness of an edifice, provided that the larva be comfortably housed? With them we must be prepared for all the inconsistencies of the unconscious artist. [[84]]

[1] Cf. The Mason-bees: chap. x.—Translator’s Note. [↑]

[2] 1.17 inch.—Translator’s Note. [↑]

[3] .58 inch.—Translator’s Note. [↑]

[[Contents]]

CHAPTER IV

THE AGENIÆ; THE PELOPÆUS’ VICTUALS

Judging only by instincts and habits, a characteristic superior to all others, we must rank not far below the builder whose nest we have been considering certain other Wasps of our country-side, Spider-hunters like the first and, like her, worthy, or perhaps even more worthy, of the title of Πηλοποιός, a worker in clay or mud, a potter. My district possesses two of these ceramic artists: Agenia punctum, Panz., and A. hyalipennis, Zetterstedt.

With all their talent they are very frail creatures, clad in black and hardly larger than the ordinary Gnat. Their pottery amazes us when we remember the feebleness of the artisan. It surprises us even more by its regularity, which may be compared with the product of the turning-lathe. Adhering broadly to a flat base and leaning one against the other, the Pelopæus’ cells, in the full elegance of the first phase, are [[85]]merely semicylinders whose circular contour is accentuated only at the mouth; while those of the Ageniæ, which are almost isolated from one another and take hold of their support only at a restricted spot, retain from end to end a regular convexity, suggesting the tiny pots of a miniature set of crockery. If any one deserves the epithet of spirifex, or turner, it is the Agenia rather than the Pelopæus. No other manipulator of potter’s clay possesses her dexterity.

The pots of A. punctum are shaped like oval jars, each smaller than a cherry-stone. Those of A. hyalipennis affect a conoid form, narrow at the base and wider at the mouth, like the primitive drinking-cup, the cyathus of the ancients. Both have a polished interior and a very much granulated exterior, the maker allowing the little mouthful of mortar which she has brought to project outside, without seeking to level it, as she does so carefully upon the inner wall. These granulations are the equivalent of the slanting fillets left by the Pelopæus. No rough-cast, no plaster is applied to conceal the pretty bit of earthenware; no reinforcement of casing is added. Such as it was when the potter moulded the neck, such [[86]]it remains after it has received its lid and its little Spider with an egg laid upon her side. The Agenia’s urns then, notwithstanding their brittleness, are left entirely unprotected, whether they be placed end to end in a winding row or grouped in a confused cluster.

Nevertheless, the mother displays a precaution unknown to the Pelopæus. A drop of water placed inside the latter’s cell quickly spreads and disappears, soaking the walls. In an Agenia’s cell it remains at the point touched, without penetrating the thickness. The urn therefore is glazed on the inner surface, like our ordinary pots, which are made watertight by the silicate of lead furnished by the potter’s galena. The waterproofing employed cannot be other than the Agenia’s saliva, an agent which is anything but plentiful, because of the insect’s exiguous dimensions, and so it is applied only on the side. Indeed, if I stand a cell on a drop of water, I see the moisture at once spread from bottom to top and turn the vessel into pulp, until nothing is left but a thin inner layer, which is less yielding.

I do not know where the Ageniæ get their materials. Do they follow the Pelopæus’ [[87]]custom and collect loam ready prepared, wet earth, mud or naturally plastic clay; or, copying the method of the Mason-bees, do they use cement scraped together atom by atom and converted into paste with the saliva? Direct observation has failed to tell me anything in this respect. From the colour of the cells, which are now red, like the soil of our stony expanses, now whitish, like the dust of the highways, now greyish, like certain chalk-beds in the neighbourhood, I see plainly that the material for the pots is collected everywhere indifferently, but I am unable to determine whether, at the actual moment of collection, it is paste or powder.

I incline, however, to the latter alternative, because of the impermeable inner surface of the cells. Earth already soaked with natural moisture would not readily absorb the Agenia’s saliva and could not acquire the watertight qualities which I find that it possesses. This peculiarity makes it highly probable that the cement is collected dry and that the insect mixes it in order to turn it into plastic clay. Then how are we to explain the outside of the pot, which melts upon contact with a drop of water, and the inside, which remains intact? [[88]]Very simply: for the outside materials the potter uses only the water with which she slakes her thirst from time to time; for the inside materials she uses pure saliva, a precious agent which has to be thriftily employed, so that she may equip her family with a sufficiency of earthenware. To construct her pots, the Agenia must possess two separate fluid-reservoirs: the crop, a bottle which is filled with spring-water; and the gland, a phial in which the watertight chemical product is sparingly elaborated.

The Pelopæus knows nothing of these scientific methods. To the mud collected ready-made she adds nothing that develops resisting-powers later; when attacked by water, her cells quickly become soaked and allow the moisture to ooze through to the inside. Hence probably, in her case, the necessity for a thick casing of plaster to protect the too permeable dwelling. Each potter has her portion: the giantess, the rough covering of loam; the dwarf, the thin coating of varnish.

Despite their inner glaze, the Agenia’s cells are too readily affected by water and moreover too fragile to remain exposed to the open air with impunity. They need a shelter quite as badly as those of the [[89]]Pelopæus. This shelter is found in all manner of places, excepting our houses, where the frail potter very rarely takes refuge. A tiny cavity under the stump of a tree; a hole in some wall or other, exposed to the sun; an old Snail-shell under a heap of stones; a Capricorn’s disused burrow bored in the oak; an Anthophora’s[1] deserted dwelling; a fat Earth-worm’s mine-shaft opening on a dry bank; the hole whence the Cicada[2] has emerged: anything, in short, suits her, provided that the accommodation be sheltered from the rain. Once only did Agenia punctum, who is more frequent than the other, pay me a visit. She had established her collection of pots in some little paper bags lying on the shelves of a green-house and intended to hold seeds. This nest-building on a sheet of paper reminded me of the Pelopæus confiding her cells to the books in a distillery or the curtains of a window. Indifferent to the nature of the support for their nests, both potters sometimes choose very curious sites. [[90]]

Now that we know the provision-jar, let us ascertain what it contains. The Pelopæus’ larvæ are fed on Spiders, a diet likewise dear to the Ageniæ and to the Pompili.[3] The game does not lack variety, even in the same nest and the same cell. Any Spider may form part of the ration, provided that her dimensions do not exceed the capacity of the jar. My abstracts of victuals mention the following genera: Epeira,[4] Segestria, Clubionus,[5] Attus, Theridion and Lycosa;[6] and the list could no doubt be extended, were it worth while to continue the bill of fare. The Epeiræ are most numerous. Those recurring most frequently belong to the following species: E. diadema, scalaris, adianta, pallida and angulata. The Diadem Epeira, or Cross Spider,[7] with three crosses of white dots on her back, is the dish that occurs oftenest.

I should hesitate to regard this frequency [[91]]as indicating a special predilection of the Pelopæus for this kind of game. In her hunting-trips the Wasp does not go far from her home; she visits the old walls near by, the hedges, the little gardens all around and captures whatever offers. Now in these conditions the Cross Spider happens, at the nesting-period, to be the commonest. Every reed-fenced garden-patch in front of the rough cottage beloved by the potter, every hawthorn-hedge surrounding a cabbage-plot shows me the Spider with the pontifical cross weaving her net or waiting for her prey in the centre of her web. If I need a Spider for my studies, I am certain of finding the Diadem Epeira within a few steps of my house. That much keener investigator, the Pelopæus, must easily effect this kind of capture; and this, it seems to me, is the reason why that particular morsel predominates in the provision-store.

If the Epeira, the habitual foundation of the meal, happen to be lacking, any other Spider is regarded as adequate, even when she belongs to a very different group. We have here the wise eclecticism of the Crabro-wasps[8] and Bembeces, who welcome any [[92]]member of the Fly clan, provided that the prey be not disproportionate to the huntress’ strength. We should be wrong, however, to erect this indifference into too absolute a principle: there is reason to believe that the Pelopæus recognizes different qualities of nourishment and flavour between one Spider and another. A more fastidious expert than Lalande,[9] with his legendary passion for plump, nutty Spiders, she must rate this species more highly than that; and there are some which she must absolutely despise. These include the House Spider (Tegenaria domestica), who weaves her cobwebs in the corners of our houses.

On the kitchen-ceiling and on the rafters of the granary this Spider is her near neighbour: the silken lair stretches in close proximity to the earthen nest. Instead of expeditions in the neighbourhood, a little patrolling of the actual premises where she has settled down would provide the Pelopæus with abundant sport, for there is game swarming at her very door. Why [[93]]does she not profit by this plenty? The dish is not to her liking; and it would be very difficult to tell the reason why. The fact remains that, in all my stock-taking of victuals, I have never found the House Spider among the provisions, although the species, if captured young, would seem to fulfil the required conditions. This disdain is a pity both for our sake and for the Pelopæus’; for ours, in the first place, because we should otherwise possess, inside our dwellings, an inspector of ceilings whose duty it would be to exterminate the spinners of cobwebs that cause the housewives such trouble; next, for the sake of the Pelopæus, who, once inscribed on the hallowed roll of useful insects, would enjoy an established reputation and receive a friendly welcome in the farm-house, instead of being driven out when too lavish with her mud.

The Spider, armed with poison-fangs, is a dangerous quarry to tackle; when of fair size, she demands of her adversary an audacity and above all a tactical skill which the Pelopæus, it seems to me, does not fully possess. Moreover, the small diameter of the cells would not admit a bulky prey, such as the Tarantula hunted by the Ringed [[94]]Calicurgus.[10] The Calicurgus deposits her corpulent victim in a cavern obtained without labour in the old plaster at the foot of a wall; the Pelopæus places hers in a jar, a laborious construction whose capacity has to be reduced to suit the larva. The Pelopæus, therefore, hunts game of moderate size, smaller than one would at first expect from the insect’s vigorous appearance. If she encounters a species that is apt to become plump, she always selects a young one. This happens in the case of the Cross Spider, who, when full-grown, with her belly swollen with eggs, almost rivals the Calicurgus’ Tarantula and who is admitted to the provision-jar only when of niggardly dimensions, very different from those which maturity will bring. For the rest, the size varies, between one specimen and another, by a hundred per cent and more. The essential point is that the quarry can be stored in the narrow jar. This variation in the size of the items provided leads to corresponding variations in their number. One cell is stuffed with a dozen Spiders; another contains only five or six. The average number is eight. The nurseling’s sex must of a surety play its part, [[95]]as with the other Wasps, in regulating the luxuries of the table.

The culminating feature in the biography of any hunting insect is the method of attack; and so I did my utmost to observe the Pelopæus at grips with her quarry. My patient waits in front of her favourite hunting-grounds, old walls and bramble-thickets, were not crowned with any great success. I have seen the Pelopæus fall suddenly upon the Spider madly fleeing and clasp and carry off her victim almost without delaying her flight. The other game-hunters alight on the ground, solemnly make their fastidious preparations and distribute their lancet-strokes with the calm deliberation which a delicate operation demands. The Pelopæus darts forward, seizes her prey and makes off, very much as the Bembeces do. There is reason to believe, so sudden is the rape, that she makes use of her sting and her mandibles only during the flight, on her journey home. This fierce procedure, which is incompatible with scientific surgery, explains even better than the narrowness of the cells her preference for Spiders of small dimensions. A sturdy prey, armed with its two poison-fangs, would constitute a deadly peril to the ravisher disdainful of precautions. [[96]]The lack of artifice calls for a feeble victim. It also makes us suspect that the Spider so hastily set upon is killed.

Indeed, I have over and over again armed my eyes with a magnifying-glass and scrutinized the contents of cells whose eggs had not yet hatched, a proof that the provisions were of recent date: there is never a quiver of either palpi or tarsi in the victims stored away. It is only with difficulty that I manage to preserve them: in ten days’ time, more or less, I see them grow mouldy and putrefy. The Spiders, therefore, are dead, or very nearly so, when they are potted by the Pelopæus. Is the skilful paralysis which the Calicurgus practises upon the Tarantula, who keeps fresh for seven weeks, unknown to the Pelopæus, or is it impracticable in the fierceness of the attack? Are we, in her case, dealing not with a delicate practitioner, who is able to abolish movement without destroying life, but rather with a brutal sacrificer, who, to deprive her victims of their power of movement, kills them? Everything in their withered aspect and their rapid decay assures us that this is so.

The evidence does not surprise me: we shall see, as we go on, other victimarii inflict [[97]]death instantly with a stroke of the stiletto, delivered with a science of slaughter no less astonishing than the science of the paralysers. We shall see the reasons that call for these complete murders and we shall recognize, under other aspects, the profound anatomical and physiological knowledge which a rational action would demand in order to rival the unconscious action of instinct. As for the necessity of killing her Spiders under which the Pelopæus labours, I find it impossible even to suspect the cause.

What I do see, without any lengthy investigations, is the logical method whereby the Pelopæus makes the most of the corpses threatened with speedy putrefaction. To begin with, each cell contains a number of victims. The carcase actually attacked by the larva, ground between its mandibles, abandoned and attacked at another point, soon becomes a shapeless and disorganized mass, more liable than ever to putrefy. But it is small and is therefore consumed at a single sitting, before decomposition overtakes it; for once the larva has bitten into a Spider it does not turn elsewhere for food. The others therefore remain intact, which is enough to preserve them in a condition of [[98]]suitable freshness during the brief period of nourishment. The numerous items composing the ration, consumed in order, one by one, are thus preserved for some days, notwithstanding that they are corpses.

Imagine, on the other hand, a single item, big enough to furnish the whole banquet; the conditions would become detestable. Nibbled here and there, the generous morsel, with its many wounds, would become a fatal mess of putrescence long before it was finished; it would poison the grub with the serum resulting from the wounds. A dish of this kind, single and sumptuous, demands, as a preliminary, the maintenance of organic life, together with the abolition of all movement, in a word, paralysis. It also demands, on the consumer’s part, a special art of eating, an art that respects the more essential and attacks the less essential by degrees, as the Scoliæ and Spheges[11] have shown us. For reasons which escape me, the Pelopæus is unacquainted with the paralysers’ art, nor does her larva know how a bulky piece of game may be consumed without danger. She is therefore very happily inspired when she [[99]]provides her family with a large number of small game. The restricted capacity of the store-houses is not the main motive that dictates her choice: there would be nothing to deter the potter from making bigger pickle-jars, were there any advantage to be gained. The preservation of dead victuals is of the foremost consequence; and, to achieve it within the brief limits of the feeding-period, the huntress fills her bag with none but the smaller Spiders.

Better still: if I open cells that have been recently closed, I always find the egg, not on the surface of the heap, on the last Spider supplied, but right at the bottom, on the piece earliest in date, the first to be stored. Whenever I witness the start of the provisioning, I see the egg lying on the single Spider wherewith the cell is then provided. There is no exception to the rule: the Pelopæus at once fixes her egg on the first morsel served up, before resuming the chase to complete the ration. The Bembeces deal similarly with their dead Flies: the first carcase stowed away receives the egg.

But this conformity of habits goes no farther. The Bembeces continue to bring provisions day by day, as the larva increases [[100]]in size, a method easily practised in a burrow closed with a mere screen of loose sand, through which the mother passes easily in either direction. The Pelopæus has not the same facilities of ingress and egress: once the earthen jar is closed and sealed, she would have, in order to reenter the cell, to break the lid, which is now dry and would offer a resistance out of all proportion to the means at the disposal of the Wasp accustomed to handling fresh mud. Moreover, each of these laborious burglaries would have to be followed by a rebuilding, which also would be an arduous task.

It is not therefore the Pelopæus’ practice to feed her offspring day by day; and the hoard of victuals is completed as swiftly as possible. If game be not abundant, if the atmospheric conditions be difficult, several days are required to fill the cell thoroughly. In favourable weather, an afternoon is sufficient. No matter what time the hunting may take, long or short according to circumstances, the laying of the egg at the bottom of the cell, on the first piece served, is a happy device on whose excellence I have already laid stress in my history of the Odynerus. The victuals provided for a cell [[101]]fill it to the brim and are stacked in the order of acquisition, with the Spiders earliest in date at the bottom and the more recent on the surface. No subsidence, which would lead to a mixture of fresh game and high, is possible, because of the game’s long legs, which in most cases scrape against the walls of the cell with their stiff hairs. The larva, at the bottom of the heap and, moreover, intent upon the morsel attacked, thus proceeds from the oldest to the less old and always finds in front of its teeth, until the end of the meal, victuals that have not had time to spoil by decomposition.

The egg is laid indifferently upon a large joint or a small, according to the chances of the first capture. It is white, cylindrical, slightly curved and measures three millimetres in length, with a diameter of rather less than one millimetre.[12] The spot that receives it on the Spider’s body varies hardly at all; it is at the beginning of the abdomen, towards the side. The new-born larva, as is usual with the Hunting Wasps, takes its first bite at the point where the pole of the egg containing the head was fixed. Thus, for its first mouthfuls, it has the juiciest and tenderest part, the Spider’s [[102]]plump belly. Next comes the thorax, abounding in muscular tissues, and lastly the legs, dry morsels, but not despised. Everything goes down, from the best to the coarsest; and, when the meal is finished, there is practically nothing left of the whole heap of Spiders. This life of gluttony lasts for eight to ten days.

The larva then works at its cocoon, which consists at first of a sack of pure, perfectly white silk, an extremely delicate sack, affording little protection to the recluse. This is only a woof, destined to become a better stuff, not by additional weaving, but by the application of a special lacquer. The spinner is a worker in oiled silk.

In the spinning-mills of the carnivorous Wasps, two methods of manufacture are employed to give the silken fabric greater toughness. On the one hand, the fabric is encrusted with numerous grains of sand, which produces an almost mineral shell wherein the silk has no other function than to serve as a cement for the stony materials. That is how the Bembeces, the Stizi, the Tachytes and the Palari work. On the other hand, the larva elaborates in its [[103]]stomach, in its chylific ventricle, a liquid varnish which it disgorges into the meshes of a rudimentary tissue of silk. Directly it trickles into the web, the varnish hardens and becomes a lacquer of exquisite daintiness. The larva next ejects at the base of the cocoon, in the form of a hard stercoral plug, the residue of the chemical process accomplished in its stomach for the elaboration of the varnish. This method is that of the Spheges, the Ammophilæ and the Scoliæ, who varnish the inner wrapper of their multiple cocoons; and of the Crabro-wasps, the Cerceres and the Philanthi,[13] whose delicate cocoon consists of only a single thickness.

The Pelopæus adopts this last procedure. When finished, her work is an amber-yellow fabric suggesting the outer skin of an onion in fineness, colour, transparency and the rustling sound which it emits when fingered. Relatively long in comparison with its width, as is demanded by the capacity [[104]]of the cell and the slender form of the future insect, the cocoon is rounded at the top and suddenly truncated at the base, which is rendered hard and opaque by the stercoral plug, the by-product of the lacquer-factory.

The hatching-period varies, of course, according to the temperature and also according to certain conditions which I am not yet in a position to specify. One cocoon, woven in July, gives birth to the perfect insect in the course of August, two or three weeks after the larva’s period of activity; another, dating from August, opens a month later, in September; a third, no matter what its date of origin during the summer quarter, goes through the winter and does not burst until the end of June. By combining the birth-certificates recorded, I seem to distinguish three generations in the year, generations which are often but not invariably realized. The first appears at the end of June: this is the one whose cocoons have gone through the winter; the second is seen in August and the third in September. So long as the very hot weather lasts, evolution is rapid: three or four weeks suffice to complete the Pelopæus’ cycle. When September arrives, the fall in [[105]]temperature puts an end to these precocious broods; and the last larvæ have to wait for the return of the hot weather before they can undergo their transformation. [[106]]

[1] For the various species of Burrowing Bees known as the Anthophoræ, cf. Bramble-bee and others: chap. vii. et passim.—Translator’s Note. [↑]

[2] For the Cicada, or Cigale, cf. The Life of the Grasshopper, by J. Henri Fabre, translated by Alexander Teixeira de Mattos: chaps. i. to v.—Translator’s Note. [↑]

[3] The Pompilus, or Ringed Calicurgus, is a Hunting Wasp, feeding her young on Spiders. Cf. The Life and Love of the Insect: chap. xii.—Translator’s Note. [↑]

[4] For the Epeiræ, or Garden Spiders, cf. The Life of the Spider: chaps. ix. to xiv.—Translator’s Note. [↑]

[5] One of the Tube-weaving Spiders.—Translator’s Note. [↑]

[6] For Theridion lugubre and the Narbonne Lycosa, or Black-bellied Tarantula, cf. The Life of the Spider: chap. i.—Translator’s Note. [↑]

[7] Cf. The Life of the Spider: chaps. vi. and vii.—Translator’s Note. [↑]

[8] A family of Digger Wasps of whom the larger species burrow in the ground and the smaller in the pith of plants or in rotten wood.—Translator’s Note. [↑]

[9] Joseph Jérôme Le Français de Lalande (1732–1807), the astronomer. Even after he had achieved his reputation, he sought means, outside the domain of science, to make himself talked about and found these in the display partly of odd tastes, such as that for eating Spiders and caterpillars, and partly of atheistical opinions.—Translator’s Note. [↑]

[10] Or Pompilus: vide supra.—Translator’s Note. [↑]

[11] For the Scolia, cf. The Life and Love of the Insect: chap. xi.; for the Sphex, cf. The Hunting Wasps: chaps. iv. to x.—Translator’s Note. [↑]

[12] .177 by .039 inch.—Translator’s Note. [↑]

[13] For the Cerceris, cf. The Hunting Wasps: chaps. i. to iii; for the Philanthus, or Bee-eating Wasp, cf. Social Life in the Insect World: chap. xiii. Some of the other Wasps mentioned above will form the subject of chapters in a later volume of this series entitled More Hunting Wasps.—Translator’s Note. [↑]

[[Contents]]

CHAPTER V

ABERRATIONS OF INSTINCT

So far as the Pelopæus is concerned, my part as an observer is concluded, a part of no great interest, I am the first to admit, if we limit its scope merely to the data which it is able to supply. That the insect frequents our dwellings, that it builds a mud nest victualled with Spiders, that it weaves itself a bag which looks as it it were cut out of an onion-skin: all these details matter to us but little. They may please the collector who zealously sets down everything, down to the nervation of a wing, in order to throw a little light on his systematic arrangements; but the mind nourished with more serious ideas sees nothing in all this but the food of an almost puerile curiosity. Is it really worth while to spend our time, the time which escapes us so swiftly, this stuff of life, as Montaigne calls it, in gleaning facts of indifferent moment and of highly contestable utility? Is it not childish to enquire so minutely into an insect’s actions? Too many interests of a graver [[107]]kind hold us in their grasp to leave us any leisure for these amusements. That is how the harsh experience of age impels us to speak; that is how I should conclude, as I bring my investigations to a close, if I did not perceive, amid the chaos of my observations, a few gleams of light touching the loftiest problems which we are privileged to discuss.

What is life? Will it ever be possible for us to trace it to its sources? Shall we ever be permitted to excite, in a drop of albumen, the uncertain quiverings which are the preludes of organization? What is human intelligence? In what respect does it differ from animal intelligence? What is instinct? Are these two mental aptitudes irreducible, or can they both be traced back to a common factor? Are the species connected with one another, are they related by evolution? Or are they, as it were, so many unchangeable medals, each struck from a separate die upon which the tooth of time has no effect, except to destroy it sooner or later? These questions are and always will be the despair of every cultivated mind, even though the inanity of our efforts to solve them urges us to cast them into the limbo of the unknowable. [[108]]The theorists, proudly daring, have an answer nowadays for every question; but, as a thousand theoretical views are not worth a single fact, thinkers untrammelled by preconceived ideas are far from being convinced. Problems such as these, whether their scientific solution be possible or not, require an enormous mass of well-established data, to which entomology, despite its humble province, can contribute a quota of some value. And that is why I am an observer, why, above all, I am an experimenter.

It is something to observe; but it is not enough: we must experiment, that is to say, we must ourselves intervene and create artificial conditions which oblige the animal to reveal to us what it would not tell if left to the normal course of events. Its actions, marvellously contrived to attain the end pursued, are capable of deceiving us as to their real meaning and of making us accept, in their linked sequence, that which our own logic dictates to us. It is not the animal that we are now consulting upon the nature of its aptitudes, upon the primary motives of its activity, but our own opinions, which always yield a reply in favour of our cherished notions. As I have already repeatedly [[109]]shown, observation in itself is often a snare: we interpret its data according to the exigencies of our theories. To bring out the truth, we must needs resort to experiment, which alone is able to some extent to fathom the obscure problem of animal intelligence. It has sometimes been denied that zoology is an experimental science. The accusation would be well-founded if zoology confined itself to describing and classifying; but this is the least important part of its function: it has higher aims than that; and, when it consults the animal upon some problem of life, its method of questioning lies in experiment. In my own modest sphere, I should be depriving myself of the most potent method of study if I were to neglect experiment. Observation sets the problem; experiment solves it, always presuming that it can be solved; or at least, if powerless to yield the full light of truth, it sheds a certain gleam over the edges of the impenetrable cloud.

Let us return to the Pelopæus, to whom it is time to apply the experimental method. A cell has recently been completed. The huntress arrives with her first Spider. She stores it away and at once fastens her egg upon the Spider’s belly. She sets out on a [[110]]second trip. I take advantage of her absence to remove with my tweezers from the bottom of the cell the head of game and the egg. What will the insect do on its return, confronted with this empty cell, this cell no longer containing the egg, the sole object of her industry as a potter and her skill as a huntress?

The disappearance of the egg must be obvious to the Wasp who has been robbed of it, if her poor intelligence possess so much as the rudimentary gleam that enables us to distinguish between a thing’s presence and its absence. The egg, were it alone, being of small dimensions, might escape the mother’s vigilance; but it lies upon a comparatively bulky Spider, of whose presence the Pelopæus, on returning to the nest, is undoubtedly apprised by her sense of touch and sight when she deposits the second victim beside the first. If this big object be missing, the egg is missing likewise, so the most elementary trace of reason that it is possible to conceive ought to tell her. Once more, what will the Pelopæus do when confronted with her cell, where the absence of the egg henceforth renders the bringing of provisions useless and absurd, unless and until she repairs the loss by laying a second [[111]]egg? She will do precisely what we have already seen in the Mason-bee of the Sheds, but under less striking conditions: she will act absurdly and wear herself out uselessly.

What she does is to bring a second Spider, whom she stores away with the same cheerful zeal as though nothing untoward had occurred; she brings a third, a fourth and others still, each of whom I remove during her absence, so that every time that she returns from the chase the warehouse is found empty. For two days the Pelopæus’ obstinacy in seeking to fill the insatiable jar persisted; for two days my patience in emptying the pot as she stocked it was equally unflagging. With the twentieth victim, persuaded, perhaps, by the fatigue of expeditions repeated beyond all measure, the huntress considered that the game-bag was sufficiently supplied; and she began most conscientiously to close the cell which contained absolutely nothing.

The Mason-bees whose cups I used to empty as and when they brushed off the pollen-dust and disgorged the honey-paste gave proof of similar inconsistencies: I would see them laying the egg in the empty cell and then closing the cell as though the provisions were still there. One point alone [[112]]used to cause me some anxiety; my plug of cotton-wool left behind it, on the wall against which it rubbed, a smear of honey whose smell might deceive the insect by concealing the absence of the victuals. The coarser sense of touch was dumb while the finer sense of smell continued to speak. In the case of the famous statue of which Condillac[1] tells us, the sole stimulant of mental activity was the scent of a rose. The insect’s intelligence is certainly very differently equipped; nevertheless we may ask ourselves whether, in a Bee, the scent of the honey would not be so far predominant as to cheat other impressions. This, at all events, would explain the laying of the egg in a cell containing no provisions, but still full of their good smell; it would explain the scrupulous sealing of the cell in which the larva is doomed to die of starvation.

To avoid those foolish objections, the [[113]]last resource of an opponent at bay, I should therefore like something better than the absurd action of the Mason-bees. And this the Pelopæus has just given us. Here we have no fragrant smear left behind by the victuals withdrawn, no vestige than can conceal the absence of provisions from the mother. The Spider whom my tweezers are about to seize at the bottom of the cell leaves no trace of her temporary sojourn, nor does the egg extracted with the first morsel, so that the Wasp cannot fail to be apprised of the void created in her cell, if she be capable of being apprised of anything. It makes no difference; nothing alters her habitual course of action. During two days, she brings a score of items, one by one, as each preceding item is removed; the stubborn hunt is prolonged, on behalf of an egg which has been absent from the outset; and at length the door of the cell is closed with the same care as under normal conditions.

Before considering the inferences to be drawn from this odd behaviour, we will record an even more striking experiment, also made at the Pelopæus’ expense. I have described how, when the group of cells is completed, the insect plasters its [[114]]nest, covering it with a thick rind of mud under which all the elegance of the pottery disappears. I surprise a Pelopæus at the moment when she is spreading her first pellets to form an outer casing. The nest is fastened to a wall coated with mortar. The idea occurs to me to take it away, in the vague hope of beholding something new. And something new there is, nay more, something so absurd that one would never have dared to foresee it. Let me begin by explaining that naught remains of the nest, when I have removed it and put it in my pocket, except a thin, broken line, marking the circumference of the clod of mud. Within this ring, save for a few fragments of mud, the wall has resumed the whiteness of its coat of mortar, a very different colour from that of the nest, which is an ashen grey.

The Pelopæus arrives with her load of clay. Without any hesitation that I can perceive, she alights on the deserted spot and deposits her pellet there, spreading it slightly. The operation would have been conducted no differently on the nest itself. Judging by the quiet and zealous way in which the Wasp is working, there is no doubt but that she really believes herself to be [[115]]plastering her house, whereas she is merely plastering its uncovered support. The new colour of the site and its flat surface, replacing the prominence of the vanished clod, fail to apprise her that the nest is gone.

Can this be a temporary distraction, a blunder due to the Wasp’s excessive eagerness for work? She will change her mind, no doubt, perceive her mistake and discontinue her futile labours. But no: I see her coming back thirty times in succession. At each trip she brings a globule of mud, which she applies, without making a single error, inside the circumference formed by the line of clay which the base of the nest has left on the wall. Her memory, which tells her nothing of the colour, shape or prominence of the nest, is surprisingly faithful in matters of topographical detail: it knows nothing of essentials but is thoroughly acquainted with accessories; topographically speaking, the nest is there; the structure, it is true, is missing, but there is the supporting base; and that, it appears, is enough; at any rate, the Pelopæus is lavish of her exertions in bringing mud to plaster the surface on which the structure no longer stands.

In the old days, the Mason-bees used to [[116]]surprise me greatly with their tenacious memory of the spot where the pebble lay supporting their nest and with their lack of perspicacity in all that concerned the nest itself, which was replaced by another, quite different nest without making them interrupt the work already begun. The Pelopæus outdoes them in these aberrations: she gives the last strokes of the trowel to an imaginary dwelling, of which nothing but the site remains.

Has she, as a matter of fact, a more obtuse intellect than the dome-builder? The entomological tribe seems hardly to swerve from a common stock of aptitudes; those whom we consider the most richly endowed, on the evidence of actions normally accomplished, show themselves as limited as the rest when the experimenter disturbs the current of their instincts. It is probable that the Mason-bee would have committed the same absurdities as the Pelopæus, had I thought of subjecting her, at a propitious time, to a similar test. A plasterer by profession, she would, like the other, have plastered the base of the nest removed from the pebble at the right moment. My confidence in the glimmer of reason which the makers of theories attribute to the animal [[117]]is so greatly shaken that I do not regard my unflattering opinion of the Mason-bee as rash.

Thirty times, I said, in my presence did the artist in earthenware lay and then spread her pellet of mud upon the bare wall, thinking that she was applying it to the nest itself. Sufficiently informed by this long perseverance, I left the Pelopæus still busy at her futile task. Two days later, I inspected the plastered site. The coating of mud did not differ from that shown by a finished nest.

I have suggested that the insect’s rudimentary intelligence has practically the same limitations everywhere. The accidental difficulty which one insect is powerless to overcome, in default of a gleam of judgment, any other, no matter what its genus or species, will be equally unable to overcome. To vary the evidence, I will borrow my next example from the Lepidoptera.[2]

The Great Peacock[3] is the largest Moth of our district. Her caterpillar, which is yellow-hued, with turquoise-blue spots surrounded [[118]]by black hairs, spins itself, at the foot of the almond-trees, a robust cocoon whose ingenious construction has long been celebrated. At the moment of her deliverance, the Mulberry Bombyx[4] has in her stomach a particular solvent which the new-born Moth disgorges against the wall of the cocoon to soften it, to dissolve the gum that sticks the threads together and in this way to force an exit by the mere pressure of her head. With the aid of this reagent, the recluse is able triumphantly to attack her silken prison at the fore-end, the rear-end or the side, as I discover by turning the chrysalis in its cocoon, which I slit with a pair of scissors and then sew up again. Whatever the spot to be perforated for the emergence, a spot which my intervention varies at will, the liquid disgorged promptly soaks into and softens the wall, whereupon the captive, struggling with her fore-limbs and pushing her forehead against the tangle of unstuck threads, makes herself a passage with the same ease as in her natural liberation.

The Great Peacock is not endowed with this method of delivery by means of a solvent; [[119]]her stomach is incapable of preparing the corrosive calculated to destroy, at any point, the defensive enclosure which is now a prison-wall. Indeed, if I reverse the chrysalis in its cocoon, opened and then closed with a few stitches, the Moth always dies, being powerless to free herself. When the point to be forced is changed, the release becomes impossible. To emerge from this shell, a genuine strong-box, a special method is therefore necessary, one having no relation to the chemical method of the Mulberry Bombyx. Let me describe, as others have done before me, how things happen.

At the fore-end of the cocoon, a conical end, whereas the other is rounded, the threads are not glued together; every elsewhere, the silken web is cemented with a gummy product that turns it into a stout, waterproof parchment. Those front threads, which are almost straight, converge at their free end and form a cone-shaped series of palisades, having as their common base the circle where the use of the gummy cement is suddenly discontinued. The arrangement can best be compared with the mouth of an Eel-pot, which the fish readily enters by following the funnel of [[120]]osier-switches, but from which the imprudent one cannot get out again, because the narrow passage closes its palisade at the least effort to push through.

Another very accurate comparison is provided by the Mouse-traps with an entrance consisting of a bunch of wires arranged in a truncated cone. Attracted by the bait, the rodent enters the orifice of the trap, enlarging it with a gentle thrust; but, when it becomes a question of departure, the wires, at first so tractable, become an insuperable barrier of halberds. Both devices permit entrance and forbid exit. If we invert the arrangement of the conical palisade, making it point outwards from within, its action is reversed: exit is permitted and entrance forbidden.

This is the case with the Great Peacock’s cocoon, which has a slight improvement to its credit: its mouth, shaped like the Eel-pot or Mouse-trap aforesaid, is formed of a numerous series of cones, fitting one within the other and overlapping. In order to emerge, the Moth has only to push her head in front of her; the several rows of uncemented threads yield without difficulty. Once the recluse is liberated, these threads resume their position, so that there is nothing [[121]]outside to show whether the cocoon is empty or inhabited.

Easy exit is not enough: there must also be an inviolable refuge during the labour of metamorphosis. The cell whose door is open for exit must have the same door closed against entrance, so that no evil-minded one may make his way inside. The mechanism of the Eel-pot’s mouth admirably fulfils this condition, which is as necessary to the safety of the Great Peacock as the first. To enter through the multiple fences of converging threads, which constitute a more effectual obstacle the harder they are pushed, would be impossible to any creature that might bethink itself of attempting to violate the dwelling. I am well-acquainted with the secrets of this lock, which contrives, like any fine piece of workmanship, to combine simple means with important results; and yet I always stand amazed when, with an open cocoon in my fingers, I try to pass a pencil through the entrance. When pushed outwards from within, it passes immediately; when pushed inwards from without, it is invincibly checked.

I am lingering over these details to show the importance which the good construction [[122]]of her palisade of threads possesses for the Great Peacock. If ill-ordered, entangled and therefore intractable when pushed, the series of boxed cones will offer an insurmountable resistance and the Moth will perish, a victim of the caterpillar’s imperfect art. If constructed with mathematical accuracy, but with sparse rows of threads in insufficient numbers, it will leave the retreat exposed to dangers from without and the chrysalis will become the prey of some intruder, of whom there are many in search of somnolent nymphs, forming easy victims. For the caterpillar, therefore, this double-acting mouth is a work of the highest importance. It has to expend upon it all that it possesses in foresight, in gleams of reason and in art capable of modification when circumstances require; it must in short give proof of the best of which its talents are capable. Let us follow it in its labours; let us interpose the experimental test; and we shall learn some curious facts.

The cocoon and its opening are constructed simultaneously. When it has woven this or that part of the general wall, the caterpillar turns about, if need be, and with its unbroken thread proceeds to continue the palisade of converging filaments. To [[123]]this end it pokes its head to the end of the roughly-defined funnel and then withdraws it, doubling the thread as it goes. This alternation of thrusts and withdrawals results in a circle of doubled filaments, which do not adhere to one another. The shift is not a long one; when the palisade is a row the richer, the caterpillar resumes its work upon the shell, a task which it again abandons to busy itself with the funnel; and so on, over and over again, the emission of the gummy product being suspended when the threads are to be left free and copiously effected when they have to be stuck together in order to obtain a solid texture.

The exit-funnel is not, as we see, a piece of work executed continuously; the caterpillar works at it intermittently, as the general shell progresses. From the beginning to the end of its spinning-period, so long as the reservoirs of silk are not exhausted, it multiplies the tiers without neglecting the rest of the cocoon. These tiers take the form of cones enclosed one within the other and of increasingly obtuse angles, until the last to be spun are so flat as to become almost level surfaces.

If nothing happen to disturb the worker, the work is performed with a perfection [[124]]that would do credit to a discerning industry capable of realizing the why and wherefore of things. Can the caterpillar be said to have any conception, however slight, of the importance of its task, of the future function of its overlapping conical palisades? This is what we are about to learn.

I take a pair of scissors and remove the conical extremity while the spinner is working at the other end. The cocoon is now wide open. The caterpillar soon turns about. It thrusts its head into the wide breach which I have just made; it seems to be exploring the outside and enquiring into the accident that has occurred. I expect to see it repair the disaster and entirely reconstruct the cone destroyed by my scissors. It does, in fact, work at it for a time; it erects a row of converging threads; then, without paying further heed to the disaster, it applies its spinnerets elsewhere and continues to thicken the cocoon.

Grave doubts come to my mind: the cone built upon the breach consists of sparse filaments; it is, moreover, very flat and does not project anything like so much as the original cone. What I took at first to be a work of repair is merely a work of continuation. [[125]]The caterpillar, put to the test by my tricks, has not modified the course of its work; despite the imminence of the danger, it has confined itself to the tier of threads which it would have fitted inside the preceding tier but for the snip of my scissors.

I let things go on for a while; and, when the mouth has once again acquired a certain solidity, I cut it off for the second time. The insect displays the same lack of perspicacity as before, replacing the absent cone by one with an even more obtuse angle, that is to say, continuing its usual task, without any attempt at a thorough restoration, despite the extreme urgency. If the store of silk were nearly at an end, I should sympathize with the troubles of the sorely-tried caterpillar doing its best to repair its house with the scanty materials that remain at its disposal; but I see it foolishly squandering its product on the additional upholstering of a shell which may be strong enough as it is, while economizing to the point of stinginess in the matter of the fence, which, if neglected, will leave the cell and its inhabitant at the mercy of the first thief that comes along. There is no lack of silk: the spinner applies layer upon layer to the [[126]]points that are unhurt; but at the breach it employs only the quantity required under ordinary conditions. This is not economy imposed by shortage; it is blind clinging to custom. And so my commiseration changes to amazement in the presence of such profound stupidity, which applies itself to the superfluous work of upholstery in a dwelling henceforth uninhabitable, instead of attending, while there is yet time, to the business of repairing the ruins.

I make my cut a third time. When the moment has come to resume the series of boxed cones, the caterpillar arms the breach with bristles arranged in a disk, as they appear in the last courses of the undisturbed structure. This configuration shows that the end of the task is at hand. The cocoon is strengthened for a little longer; then rest ensues and the metamorphosis begins in a dwelling with a niggardly fence to it, one which would not strike terror into the puniest invader.

To sum up, the caterpillar, incapable of perceiving the dangers attendant upon an incomplete palisade, resumes its work, after each amputation of the cocoon, at the point where it had left it before the accident. Instead of thoroughly restoring the ruined [[127]]exit, which its very abundant store of silk would allow it to do; instead of reerecting on the breach a projecting cone of many layers, to replace the one removed by my scissors, it runs up layers of threads that become gradually flatter and flatter and form a continuation and not a reconstruction of the missing layers. Moreover, this work of fence-building, the need for which would seem imperious to any reasoning creature, does not appear to preoccupy the caterpillar more than usual, for it keeps on alternating this work with that of the cocoon, which is much less urgent. Everything goes by rote, as though the serious incident of the housebreaking had not occurred. In a word, the caterpillar does not begin all over again a thing once made and then destroyed; it continues it. The early stages of the work are lacking; no matter: the sequel follows without any modification in the plans.

It would be easy for me, if my argument were not already quite clear, to give a host of similar examples showing plainly that the intelligence of the insect is absolutely deficient in rational discernment, even when the great perfection of the work would seem to allow the artisan a certain perspicacity. [[128]]We will confine ourselves for the moment to the three cases which I have mentioned. The Pelopæus goes on storing Spiders for an egg that has been removed; she perseveres in making hunting-trips that are henceforth useless; she hoards victuals that are destined to nourish nothing; she multiplies her battues to fill with game a larder which is forthwith emptied by my tweezers; lastly, she closes, with every customary care, a cell that no longer contains anything whatever: she sets her seal on emptiness. She does even absurder things: she plasters the site of her vanished nest, covering an imaginary structure and putting a roof to a house which at the moment is tucked away in my pocket. In the case of the Great Peacock, the caterpillar, despite the certain loss of the coming Moth, instead of beginning all over again the mouth of the Eel-pot cut down by my scissors, quietly continues its spinning, without in any way modifying the regular course of the work; and, when the time comes for making the last tiers of defensive filaments, it erects them upon the dangerous breach, but neglects to rebuild the ruined portion of the barricade. Indifferent to the indispensable, it occupies itself with the superfluous. [[129]]

What are we to conclude from these facts? I would fain believe, for the sake of my insects’ reputation, in some distraction on their part, in some individual giddiness which would not taint the general perspicacity; I should like to regard their aberrations merely as isolated and exceptional actions, which would not affect their judgment as a whole. Alas, a long series of glaring facts would impose silence on my attempts at rehabilitation! Any species, no matter which, when subjected to experimental tests, is guilty of similar inconsistencies in the course of its disturbed industry. Constrained by the inexorable logic of the facts, I therefore state the deductions suggested by observation as follows: the insect is neither free nor conscious in its industry, which in its case is an external function with phases regulated almost as strictly as the phases of an internal function, such as digestion. It builds, weaves, hunts, stabs and paralyses, even as it digests, even as it secretes the poison of its sting, the silk of its cocoon or the wax of its combs, always without the least understanding of the means or the end. It is ignorant of its wonderful talents just as the stomach is ignorant of its skilful chemistry. [[130]]It can add nothing essential to them nor subtract anything from them, any more than it is able to increase or diminish the pulsations of its dorsal vessel.

Test it with an accident and you affect it not at all: such as it is in the undisturbed exercise of its calling, such it will remain should circumstances arise demanding some modification in the conduct of its task. Experience does not teach it; time does not awaken a glimmer in the darkness of its unconsciousness. Its art, perfect in its speciality, but inept in the face of the slightest new difficulty, is handed down immutably, as the art of the suction-pump is handed down to the babe at the breast. To expect the insect to alter the essential points of its industry is to hope that the babe will change its manner of sucking. Both equally ignorant of what they are doing, they persevere in the method prescribed for the safeguarding of the species, precisely because their ignorance forbids them to make any sort of essay or attempt.

The insect, then, lacks the aptitude for reflection, the aptitude that harks back and reverts to the antecedent, without which the consequent would lose all its value. In the phases of its industry, each action accomplished [[131]]counts as valid by the mere fact that it has been accomplished; the insect does not go back to it, should some accident demand; the consequent follows without troubling about the missing antecedent. A blind impulse urges it from one act to a second, from this second to a third and so on until the task is completed; but it is impossible for the insect to reascend the current of its activity should accidental conditions arise and call for this, however imperatively. Having passed through the complete cycle, the work is considered to be most logically performed by a worker devoid of all logic.

The stimulus to labour is the bait of pleasure, that chief motive-power in the animal. The mother has no foreknowledge whatever of her future larva; she does not build, does not hunt, does not hoard with the conscious aim of rearing a family. The real object of her work is hidden from her; the accessory but exciting aim, the pleasure experienced, is her only guide. The Pelopæus feels a keen satisfaction when she crams a cell full with Spiders; and she goes on hunting with imperturbable spirit after the removal of the egg from the cell has made provisions useless. She delights in [[132]]plastering the outside of her nest with mud and she continues to putty the site of her nest, after it has been detached from the wall, without suspecting the futility of her stucco. And so with the others. To reproach them for their aberrations we must assume that they possess a tiny glimmer of reason, as Darwin[5] would have us believe; if they have it not, the reproach falls to the ground and their aberrant acts are the inevitable result of an unconsciousness diverted from its normal paths. [[133]]

[1] Étienne Bonnot de Condillac, Abbé de Mureaux (1715–1780), the leading exponent of sensual philosophy. His most important work is a Traité des sensations, in which he imagines a statue organized like a man and endows it with the senses one by one, beginning with that of smell. He argues by a process of imaginative reconstruction that all human faculties and all human knowledge are merely transformed sensations, to the exclusion of any other principle; in short, that everything has its source in sensation: man is nothing but what he has acquired.—Translator’s Note. [↑]

[2] The order of insects consisting of the Butterflies and Moths.—Translator’s Note. [↑]

[3] Cf. The Life of the Caterpillar, by J. Henri Fabre, translated by Alexander Teixeira de Mattos: chap. xi.—Translator’s Note. [↑]

[4] Bombyx mori, the Moth of the Silkworm.—Translator’s Note. [↑]

[5] Charles Robert Darwin (1809–1882), the author of The Origin of Species, had the highest opinion of Fabre and spoke of him as “that incomparable observer.” Fabre, on the other hand, had no faith whatever in Darwinism, nor was he greatly struck by the views and the suggestions for experiments with which Darwin favoured him from time to time. Cf. The Mason-bees: chaps. iv. and v.—Translator’s Note. [↑]

[[Contents]]

CHAPTER VI

THE SWALLOW AND THE SPARROW

The Pelopæus sets us a second problem. She frequents our homes, seeks the warmth of our fireplaces. A nest like hers, built of soft mud, which lets in the water, which would be dismantled by a shower and utterly destroyed by prolonged damp, must have a dry shelter; and this can be nowhere better found than in our dwelling-houses. Her susceptibility to cold makes warmth a necessity. Perhaps she is a foreigner not yet fully acclimatized, an emigrant from the shores of Africa, who, after coming from the land of dates to the land of olives, finds the sunshine in the latter insufficient and substitutes for the climate beloved of her race the artificial climate of the fireside. This would explain her habits, so unlike those of the other Wasps, all of whom shun the too-close proximity of man.

But through what stages did she pass before becoming our guest? Where did she lodge before quarters built by human industry existed, where did she shelter her [[134]]brood of grubs before chimneys were thought of? When, on the hills near by, abounding in traces of their sojourn, the aborigines of Sérignan were hewing weapons out of flint, scraping Goat-skins into raiment and building huts of mud and branches, did the Pelopæus already frequent their cabins? Did she build in some bulging pot, shaped with the thumb out of half-baked black clay, and by this choice teach her latter-day descendants to seek out the peasant’s gourd on the chimneypiece? Did she think of building in the folds of the garments, the spoils of the Wolf and the Bear, hanging from some set of antlers, the hat-rack of the period, thus trying her hand at a kind of annexation that was to take her at a later date to window-curtains and the labourer’s smock? Did she prefer to fix her nest on the rough wall of branches and clay, near the conical orifice which let out the smoke from the primitive fire laid between four stones in the centre of the hut? Though not equal to our present chimneys, it will have served at a pinch.

What progress she has made, this Pelopæus, what a contrast between that miserable beginning and her modern premises, if she is really, in my district, a contemporary [[135]]of the aborigines! She too must have profited greatly by civilization: she has managed to turn man’s increasing comfort into her own. When the dwelling with a roof, rafters and ceiling was planned and the chimney with side-walls and a flue invented, the chilly creature said to herself:

“How pleasant this is! Let us pitch our tent here.”

And, notwithstanding the novelty of her surroundings, she hastened to take possession.

Let us go back farther still. Before huts existed, before the niche in the rock, before man himself, the last to make his entrance on the world’s stage, where did the Pelopæus build? The question is not devoid of interest, as we shall shortly see. Besides, it does not stand alone. Where did the Window-swallow and the Chimney-swallow make their nests before there were windows and chimneys to build in? What retreat did the Sparrow select for his family before there were roofs with tiles and walls with holes to them?

“As a sparrow all alone on the house-top,” said the Psalmist in his day.

In King David’s time, the Sparrow squawked mournfully under the eaves in the [[136]]summer heat, as he does to this day. The buildings of that period differed but little from ours, at least so far as the Sparrow’s convenience was concerned; and the shelter under the tile had been adopted long before. But, when Palestine had nothing more than the camel-hair tent, where did the Sparrow then elect to make his home?

When Virgil sings to us of good Evander, who, preceded by his watch, two Sheep-dogs, visits Æneas, his guest, he shows him to us awakened at dawn by the singing of the birds:

Evandrum ex humili tecto lux alma

Et matutini volucrum sub culmine cantus.[1]

What could those birds be which, at break of day, twittered under the roof of the old King of Latium? I see only two: the Swallow and the Sparrow, both of them chanticleers of my hermitage and as punctual as in the Saturnian days. There was nothing princely about Evander’s palace. The poet does not conceal the fact, it was a lowly roof: humili tecto, he says. Besides, the furniture enlightens us as to the [[137]]edifice. The illustrious guest is given a Bear-skin and a heap of leaves for a bed:

… stratisque locavit

Effultum foliis et pelle Libystidis ursæ.[2]

Evander’s Louvre therefore was a cabin a little larger than the others, made perhaps of tree-trunks laid one on top of the other, perhaps of unhewn stone employed as found, perhaps of reeds and clay. This rustic palace would have a thatched roof, of course. However primitive the habitation was, the Swallow and Sparrow were there, at least the poet says so. But where did they stay before they found a lodging in man’s abode?

The industry of the Sparrow, the Swallow, the Pelopæus and many others cannot be subordinate to mankind’s: each of them must possess a primordial art of building, one which makes the best use of the site within reach. If better conditions present themselves, they profit thereby; if these conditions are lacking, they go back to their ancient customs, whose practice, though [[138]]sometimes exacting more labour, is at least always possible.

		PAGE
	[TRANSLATOR’S NOTE]	v
CHAPTER
I	[THE EUMENES]	1
II	[THE ODYNERI]	28
III	[THE PELOPÆUS]	60
IV	[THE AGENIÆ; THE PELOPÆUS’ VICTUALS]	84
V	[ABERRATIONS OF INSTINCT]	106
VI	[THE SWALLOW AND THE SPARROW]	133
VII	[INSTINCT AND DISCERNMENT]	155
VIII	[THE NEST-BUILDING ODYNERUS]	176
IX	[INSECT GEOMETRY]	219
X	[THE COMMON WASP]	240
XI	[THE COMMON WASP (continued)]	270
XII	[THE VOLUCELLA]	288
	[INDEX]	313

The Mason-Wasps

CONTENTS

TRANSLATOR’S NOTE

THE MASON-WASPS

CHAPTER I

THE EUMENES

CHAPTER II

THE ODYNERI

CHAPTER III

THE PELOPÆUS

CHAPTER IV

THE AGENIÆ; THE PELOPÆUS’ VICTUALS

CHAPTER V

ABERRATIONS OF INSTINCT

CHAPTER VI

THE SWALLOW AND THE SPARROW