Bramble-Bees and Others - Part 2
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Part 2

by J. Henri Fabre, translated by Alexander Teixeira de Mattos: pa.s.sim.--Translator's Note.), provided me with no precise result.

The Leaf-cutting Bee (Megachile apicalis, SPIN. (Cf. Chapter 8 of the present volume.--Translator's Note.)), who builds her leafy cups in the old cells of the Chalicodoma of the Walls, acts like the Solenius and directs her whole column towards the same outlet.

Incomplete as it is, this symmetry shows us how unwise it were to generalize from the conclusions to which the Three-p.r.o.nged Osmia leads us. Whereas some Bees, such as the Anthidium and the Chalicodoma, share the Osmia's talent for using the twofold exit, others, such as the Solenius and the Leaf-cutter, behave like a flock of sheep and follow the first that goes out. The entomological world is not all of a piece; its gifts are very various: what one is capable of doing another cannot do; and penetrating indeed would be the eyes that saw the causes of these differences. Be this as it may, increased research will certainly show us a larger number of species qualified to use the double outlet.

For the moment, we know three; and that is enough for our purpose.

I will add that, when the horizontal tube has one of its ends closed, the whole string of Osmiae makes for the open end, turning round to do so, if need be.

Now that the facts are set forth, let us, if possible, trace the cause.

In a horizontal tube, gravity no longer acts to determine the direction which the insect will take. Is it to attack the part.i.tion on the right or that on the left? How shall it decide? The more I look into the matter, the more do my suspicions fall upon the atmospheric influence which is felt through the two open ends. Of what does this influence consist? Is it an effect of pressure, of hygrometry, of electrical conditions, of properties that escape our coa.r.s.er physical attunement?

He were a bold man who should undertake to decide. Are not we ourselves, when the weather is about to alter, subject to subtle impressions, to sensations which we are unable to explain? And yet this vague sensitiveness to atmospheric changes would not be of much help to us in circ.u.mstances similar to those of my anchorites. Imagine ourselves in the darkness and the silence of a prison-cell, preceded and followed by other similar cells. We possess implements wherewith to pierce the walls; but where are we to strike to reach the final outlet and to reach it with the least delay? Atmospheric influence would certainly never guide us.

And yet it guides the insect. Feeble though it be, through the multiplicity of part.i.tions, it is exercised on one side more than on the other, because the obstacles are fewer; and the insect, sensible to the difference between those two uncertainties, unhesitatingly attacks the part.i.tion which is nearer to the open air. Thus is decided the division of the column into two converse sections, which accomplish the total liberation with the least aggregate of work. In short, the Osmia and her rivals 'feel' the free s.p.a.ce. This is yet one more sensory faculty which evolution might well have left us, for our greater advantage. As it has not done so, are we then really, as many contend, the highest expression of the progress accomplished, throughout the ages, by the first atom of glair expanded into a cell?

CHAPTER 2. THE OSMIAE.

February has its sunny days, heralding spring, to which rude winter will reluctantly yield place. In snug corners, among the rocks, the great spurge of our district, the characias of the Greeks, the jusclo of the Provencals, begins to lift its drooping inflorescence and discreetly opens a few sombre flowers. Here the first Midges of the year will come to slake their thirst. By the time that the tip of the stalks reaches the perpendicular, the worst of the cold weather will be over.

Another eager one, the almond-tree, risking the loss of its fruit, hastens to echo these preludes to the festival of the sun, preludes which are too often treacherous. A few days of soft skies and it becomes a glorious dome of white flowers, each twinkling with a roseate eye.

The country, which still lacks green, seems dotted everywhere with white-satin pavilions. 'Twould be a callous heart indeed that could resist the magic of this awakening.

The insect nation is represented at these rites by a few of its more zealous members. There is first of all the Honey-bee, the sworn enemy of strikes, who profits by the least lull of winter to find out if some rosemary is not beginning to open somewhere near the hive. The droning of the busy swarm fills the flowery vault, while a snow of petals falls softly to the foot of the tree.

Together with the population of harvesters there mingles another, less numerous, of mere drinkers, whose nesting-time has not yet begun.

This is the colony of the Osmiae, with their copper-coloured skin and bright-red fleece. Two species have come hurrying up to take part in the joys of the almond-tree: first, the Horned Osmia, clad in black velvet on the head and breast and in red velvet on the abdomen; and, a little later, the Three-horned Osmia, whose livery must be red and red only.

These are the first delegates despatched by the pollen-gleaners to ascertain the state of the season and attend the festival of the early blooms. 'Tis but a moment since they burst their coc.o.o.n, the winter abode: they have left their retreats in the crevices of the old walls; should the north wind blow and set the almond-tree shivering, they will hasten to return to them. Hail to you, O my dear Osmiae, who yearly, from the far end of the harmas (The piece of waste ground in which the author studied his insects in their natural state. Cf. "The Life of the Fly" by J. Henri Fabre, translated by Alexander Teixeira de Mattos: chapter 1.--Translator's Note.), opposite snow-capped Ventoux (A mountain in the Provencal Alps, near Carpentras and Serignan, 6,271 feet.--Translator's Note.), bring me the first tidings of the awakening of the insect world! I am one of your friends; let us talk about you a little.

Most of the Osmiae of my region have none of the industry of their kinswomen of the brambles, that is to say, they do not themselves prepare the dwelling destined for the laying. They want ready-made lodgings, such as the old cells and old galleries of Anthophorae and Chalicodomae. If these favourite haunts are lacking, then a hiding-place in the wall, a round hole in some bit of wood, the tube of a reed, the spiral of a dead Snail under a heap of stones are adopted, according to the tastes of the several species. The retreat selected is divided into chambers by part.i.tion-walls, after which the entrance to the dwelling receives a ma.s.sive seal. That is the sum-total of the building done.

For this plasterer's rather than mason's work, the Horned and the Three-horned Osmia employ soft earth. This material is different from the Mason-bee's cement, which will withstand wind and weather for many years on an exposed pebble; it is a sort of dried mud, which turns to pap on the addition of a drop of water. The Mason-bee gathers her cementing-dust in the most frequented and driest portions of the road; she wets it with a saliva which, in drying, gives it the consistency of stone. The two Osmiae who are the almond-tree's early visitors are no chemists: they know nothing of the making and mixing of hydraulic mortar; they limit themselves to gathering natural soaked earth, mud in short, which they allow to dry without any special preparation on their part; and so they need deep and well-sheltered retreats, into which the rain cannot penetrate, or the work would fall to pieces.

While exploiting, in friendly rivalry with the Three-horned Osmia, the galleries which the Mason-bee of the Sheds good-naturedly surrenders to both, Latreille's Osmia uses different materials for her part.i.tions and her doors. She chews the leaves of some mucilaginous plant, some mallow perhaps, and then prepares a sort of green putty with which she builds her part.i.tions and finally closes the entrance to the dwelling. When she settles in the s.p.a.cious cells of the Masked Anthophora (Anthophora personata, ILLIG.), the entrance to the gallery, which is wide enough to admit one's finger, is closed with a voluminous plug of this vegetable paste. On the earthy banks, hardened by the sun, the home is then betrayed by the gaudy colour of the lid. It is as though the authorities had closed the door and affixed to it their great seals of green wax.

So far then as their building-materials are concerned, the Osmiae whom I have been able to observe are divided into two cla.s.ses: one building compartments with mud, the other with a green-tinted vegetable putty.

The first section includes the Horned Osmia and the Three-horned Osmia, both so remarkable for the h.o.r.n.y tubercles on their faces.

The great reed of the south, the Arundo donax, is often used, in the country, for rough garden-shelters against the mistral or just for fences. These reeds, the ends of which are chopped off to make them all the same length, are planted perpendicularly in the earth. I have often explored them in the hope of finding Osmia-nests. My search has very seldom succeeded. The failure is easily explained. The part.i.tions and the closing-plug of the Horned and of the Three-horned Osmia are made, as we have seen, of a sort of mud which water instantly reduces to pap.

With the upright position of the reeds, the stopper of the opening would receive the rain and would become diluted; the ceilings of the storeys would fall in and the family would perish by drowning. Therefore the Osmia, who knew of these drawbacks before I did, refuses the reeds when they are placed perpendicularly.

The same reed is used for a second purpose. We make canisses of it, that is to say, hurdles, which, in spring, serve for the rearing of silk-worms and, in autumn, for the drying of figs. At the end of April and during May, which is the time when the Osmiae work, the canisses are indoors, in the silk-worm nurseries, where the Bee cannot take possession of them; in autumn, they are outside, exposing their layers of figs and peeled peaches to the sun; but by that time the Osmiae have long disappeared. If, however, during the spring, an old, disused hurdle is left out of doors, in a horizontal position, the Three-horned Osmia often takes possession of it and makes use of the two ends, where the reeds lie truncated and open.

There are other quarters that suit the Three-horned Osmia, who is not particular, it seems to me, and will make shift with any hiding-place, so long as it has the requisite conditions of diameter, solidity, sanitation and kindly darkness. The most original dwellings that I know her to occupy are disused Snail-sh.e.l.ls, especially the house of the Common Snail (Helix aspersa). Let us go to the slope of the hills thick with olive-trees and inspect the little supporting-walls which are built of dry stones and face the south. In the crevices of this insecure masonry, we shall reap a harvest of old Snail-sh.e.l.ls, plugged with earth right up to the orifice. The family of the Three-horned Osmia is settled in the spiral of those sh.e.l.ls, which is subdivided into chambers by mud part.i.tions.

Let us inspect the stone-heaps, especially those which come from the quarry-works. Here we often find the Field-mouse sitting on a gra.s.s mattress, nibbling acorns, almonds, olive-stones and apricot-stones. The Rodent varies his diet: to oily and farinaceous foods he adds the Snail.

When he is gone, he has left behind him, under the overhanging stones, mixed up with the remains of other victuals, an a.s.sortment of empty sh.e.l.ls, sometimes plentiful enough to remind me of the heap of Snails which, cooked with spinach and eaten country-fashion on Christmas Eve, are flung away next day by the housewife. This gives the Three-horned Osmia a handsome collection of tenements; and she does not fail to profit by them. Then again, even if the Field-mouse's conchological museum be lacking, the same broken stones serve as a refuge for Garden-snails who come to live there and end by dying there. When we see Three-horned Osmiae enter the crevices of old walls and of stone-heaps, there is no doubt about their occupation: they are getting free lodgings out of the old Snail-sh.e.l.ls of those labyrinths.

The Horned Osmia, who is less common, might easily also be less ingenious, that is to say, less rich in varieties of houses. She seems to scorn empty sh.e.l.ls. The only homes that I know her to inhabit are the reeds of the hurdles and the deserted cells of the Masked Anthophora.

All the other Osmiae whose method of nest-building I know work with green putty, a paste made of some crushed leaf or other; and none of them, except Latreille's Osmia, is provided with the horned or tubercled armour of the mud-kneaders. I should like to know what plants are used in making the putty; probably each species has its own preferences and its little professional secrets; but hitherto observation has taught me nothing concerning these details. Whatever worker prepare it, the putty is very much the same in appearance. When fresh, it is always a clear dark green. Later, especially in the parts exposed to the air, it changes, no doubt through fermentation, to the colour of dead leaves, to brown, to dull-yellow; and the leafy character of its origin is no longer apparent. But uniformity in the materials employed must not lead us to believe in uniformity in the lodging; on the contrary, this lodging varies greatly with the different species, though there is a marked predilection in favour of empty sh.e.l.ls. Thus Latreille's Osmia, together with the Three-horned Osmia, uses the s.p.a.cious structures of the Mason-bee of the Sheds; she likes the magnificent cells of the Masked Anthophora; and she is always ready to establish herself in the cylinder of any reed lying flat on the ground.

I have already spoken of an Osmia (O. cyanoxantha, PEREZ) who elects to make her home in the old nests of the Mason-bee of the Pebbles. (Cf.

"The Mason-bees": chapter 10.--Translator's Note.) Her closing-plug is made of a stout concrete, consisting of fair-sized bits of gravel sunk in the green paste; but for the inner part.i.tions she employs only unalloyed putty. As the outer door, situated on the curve of an unprotected dome, is exposed to the inclemencies of the weather, the mother has to think of fortifying it. Danger, no doubt, is the originator of that gritty concrete.

The Golden Osmia (O. aurulenta, LATR.) absolutely insists on an empty Snail-sh.e.l.l as her residence. The Brown or Girdled Snail, the Garden Snail and especially the Common Snail, who has a more s.p.a.cious spiral, all scattered at random in the gra.s.s, at the foot of the walls and of the sun-swept rocks, furnish her with her usual dwelling-house. Her dried putty is a kind of felt full of short white hairs. It must come from some hairy-leaved plant, one of the Boragineae perhaps, rich both in mucilage and the necessary bristles.

The Red Osmia (O. rufo-hirta, LATR.) has a weakness for the Brown Snail and the Garden Snail, in whose sh.e.l.ls I find her taking refuge in April when the north-wind blows. I am not yet much acquainted with her work, which should resemble that of the Golden Osmia.

The Green Osmia (O. viridana, MORAWITZ) takes up her quarters, tiny creature that she is, in the spiral staircase of Bulimulus radiatus. It is a very elegant, but very small lodging, to say nothing of the fact that a considerable portion is taken up with the green-putty plug. There is just room for two.

The Andrenoid Osmia (O. andrenoides, LATR.), who looks so curious, with her naked red abdomen, appears to build her nest in the sh.e.l.l of the Common Snail, where I discover her refuged.

The Variegated Osmia (O. versicolor, LATR.) settles in the Garden Snail's sh.e.l.l, almost right at the bottom of the spiral.

The Blue Osmia (O. cyanea, KIRB.) seems to me to accept many different quarters. I have extracted her from old nests of the Mason-bee of the Pebbles, from the galleries dug in a roadside bank by the Colletes (A short-tongued Burrowing-bee known also as the Melitta.--Translator's Note.) and lastly from the cavities made by some digger or other in the decayed trunk of a willow-tree.

Morawitz' Osmia (O. Morawitzi, PEREZ) is not uncommon in the old nests of the Mason-bee of the Pebbles, but I suspect her of favouring other lodgings besides.

The Three-p.r.o.nged Osmia (O. tridentata, DUF. and PER.) creates a home of her own, digging herself a channel with her mandibles in dry bramble and sometimes in danewort. It mixes a few sc.r.a.pings of perforated pith with the green paste. Its habits are shared by the Ragged Osmia (O. detrita, PEREZ) and by the Tiny Osmia (O. parvula, DUF.)

The Chalicodoma works in broad daylight, on a tile, on a pebble, on a branch in the hedge; none of her trade-practises is kept a secret from the observer's curiosity. The Osmia loves mystery. She wants a dark retreat, hidden from the eye. I would like, nevertheless, to watch her in the privacy of her home and to witness her work with the same facility as if she were nest-building in the open air. Perhaps there are some interesting characteristics to be picked up in the depths of her retreats. It remains to be seen whether my wish can be realized.

When studying the insect's mental capacity, especially its very retentive memory for places, I was led to ask myself whether it would not be possible to make a suitably-chosen Bee build in any place that I wished, even in my study. And I wanted, for an experiment of this sort, not an individual but a numerous colony. My preference leant towards the Three-horned Osmia, who is very plentiful in my neighbourhood, where, together with Latreille's Osmia, she frequents in particular the monstrous nests of the Chalicodoma of the Sheds. I therefore thought out a scheme for making the Three-horned Osmia accept my study as her settlement and build her nests in gla.s.s tubes, through which I could easily watch the progress. To these crystal galleries, which might well inspire a certain distrust, were to be added more natural retreats: reeds of every length and thickness and disused Chalicodoma-cells taken from among the biggest and the smallest. A scheme like this sounds mad.

I admit it, while mentioning that perhaps none ever succeeded so well with me. We shall see as much presently.

My method is extremely simple. All I ask is that the birth of my insects, that is to say, their first seeing the light, their emerging from the coc.o.o.n, should take place on the spot where I propose to make them settle. Here there must be retreats of no matter what nature, but of a shape similar to that in which the Osmia delights. The first impressions of sight, which are the most long-lived of any, shall bring back my insects to the place of their birth. And not only will the Osmiae return, through the always open windows, but they will always nidify on the natal spot if they find something like the necessary conditions.

And so, all through the winter, I collect Osmia-coc.o.o.ns, picked up in the nests of the Mason-bee of the Sheds; I go to Carpentras to glean a more plentiful supply in the nests of the Hairy-footed Anthophora, that old acquaintance whose wonderful cities I used to undermine when I was studying the history of the Oil-beetles. (This study is not yet translated into English; but cf. "The Life of the Fly": chapters 2 and 4.--Translator's Note.) Later, at my request, a pupil and intimate friend of mine, M. Henri Devillario, president of the civil court at Carpentras, sends me a case of fragments broken off the banks frequented by the Hairy-footed Anthophora and the Anthophora of the Walls, useful clods which furnish a handsome adjunct to my collection. Indeed, at the end, I find myself with handfuls of coc.o.o.ns of the Three-horned Osmia.

To count them would weary my patience without serving any particular purpose.

I spread out my stock in a large open box on a table which receives a bright diffused light but not the direct rays of the sun. The table stands between two windows facing south and overlooking the garden. When the moment of hatching comes, those two windows will always remain open to give the swarm entire liberty to go in and out as it pleases.

The gla.s.s tubes and the reed-stumps are laid here and there, in fine disorder, close to the heap of coc.o.o.ns and all in a horizontal position, for the Osmia will have nothing to do with upright reeds. The hatching of some of the Osmiae will therefore take place under cover of the galleries destined to be the building-yard later; and the site will be all the more deeply impressed on their memory. When I have made these comprehensive arrangements, there is nothing more to be done; and I wait patiently for the building-season to open.

My Osmiae leave their coc.o.o.ns in the second half of April. Under the immediate rays of the sun, in well-sheltered nooks, the hatching would occur a month earlier, as we can see from the mixed population of the snowy almond-tree. The constant shade in my study has delayed the awakening, without, however, making any change in the nesting-period, which synchronizes with the flowering of the thyme. We now have, around my working-table, my books, my jars and my various appliances, a buzzing crowd that goes in and out of the windows at every moment. I enjoin the household henceforth not to touch a thing in the insects' laboratory, to do no more sweeping, no more dusting. They might disturb the swarm and make it think that my hospitality was not to be trusted. I suspect that the maid, wounded in her self-esteem at seeing so much dust acc.u.mulating in the master's study, did not always respect my prohibitions and came in stealthily, now and again, to give a little sweep of the broom.

At any rate, I came across a number of Osmiae who seemed to have been crushed under foot while taking a sunbath on the floor in front of the window. Perhaps it was I myself who committed the misdeed in a heedless moment. There is no great harm done, for the population is a numerous one; and, notwithstanding those crushed by inadvertence, notwithstanding the parasites wherewith many of the coc.o.o.ns are infested, notwithstanding those who may have come to grief outside or been unable to find their way back, notwithstanding the deduction of one-half which we must make for the males: notwithstanding all this, during four or five weeks I witness the work of a number of Osmiae which is much too large to allow of my watching their individual operations. I content myself with a few, whom I mark with different-coloured spots to distinguish them; and I take no notice of the others, whose finished work will have my attention later.

The first to appear are the males. If the sun is bright, they flutter around the heap of tubes as if to take careful note of the locality; blows are exchanged and the rival swains indulge in mild skirmishing on the floor, then shake the dust off their wings and fly away. I find them, opposite my window, in the refreshment-bar of the lilac-bush, whose branches bend with the weight of their scented panicles. Here the Bees get drunk with sunshine and draughts of honey. Those who have had their fill come home and fly a.s.siduously from tube to tube, placing their heads in the orifices to see if some female will at last make up her mind to emerge.

One does, in point of fact. She is covered with dust and has the disordered toilet that is inseparable from the hard work of the deliverance. A lover has seen her, so has a second, likewise a third.

All crowd round her. The lady responds to their advances by clashing her mandibles, which open and shut rapidly, several times in succession. The suitors forthwith fall back; and they also, no doubt to keep up their dignity, execute savage mandibular grimaces. Then the beauty retires into the arbour and her wooers resume their places on the threshold. A fresh appearance of the female, who repeats the play with her jaws; a fresh retreat of the males, who do the best they can to flourish their own pincers. The Osmiae have a strange way of declaring their pa.s.sion: with that fearsome gnashing of their mandibles, the lovers look as though they meant to devour each other. It suggests the thumps affected by our yokels in their moments of gallantry.

The ingenious idyll is soon over. By turns greeting and greeted with a clash of jaws, the female leaves her gallery and begins impa.s.sively to polish her wings. The rivals rush forward, hoist themselves on top of one another and form a pyramid of which each struggles to occupy the base by toppling over the favoured lover. He, however, is careful not to let go; he waits for the strife overhead to calm down; and, when the supernumeraries realize that they are wasting their time and throw up the game, the couple fly away far from the turbulent rivals. This is all that I have been able to gather about the Osmia's nuptials.

The females, who grow more numerous from day to day, inspect the premises; they buzz outside the gla.s.s galleries and the reed dwellings; they go in, stay for a while, come out, go in again and then fly away briskly into the garden. They return, first one, then another. They halt outside, in the sun, on the shutters fastened back against the wall; they hover in the window-recess, come inside, go to the reeds and give a glance at them, only to set off again and to return soon after. Thus do they learn to know their home, thus do they fix their birthplace in their memory. The village of our childhood is always a cherished spot, never to be effaced from our recollection. The Osmia's life endures for a month; and she acquires a lasting remembrance of her hamlet in a couple of days. 'Twas there that she was born; 'twas there that she loved; 'tis there that she will return. Dulces reminiscitur Argos. ('Now falling by another's wound, his eyes He casts to heaven, on Argos thinks and dies.'--"Aeneid," Book 10 Dryden's translation.)

At last each has made her choice. The work of construction begins; and my expectations are fulfilled far beyond my wishes. The Osmiae build nests in all the retreats which I have placed at their disposal. The gla.s.s tubes, which I cover with a sheet of paper to produce the shade and mystery favourable to concentrated toil, do wonderfully well. All, from first to last, are occupied. The Osmiae quarrel for the possession of these crystal palaces, hitherto unknown to their race. The reeds and the paper tubes likewise do wonderfully. The number provided is too small; and I hasten to increase it. Snail-sh.e.l.ls are recognized as excellent abodes, though deprived of the shelter of the stone-heap; old Chalicodoma-nests, down to those of the Chalicodoma of the Shrubs (Cf.

"The Mason-bees": chapters 4 and 10.--Translator's Note.), whose cells are so small, are eagerly occupied. The late-comers, finding nothing else free, go and settle in the locks of my table-drawers. There are daring ones who make their way into half-open boxes containing ends of gla.s.s tubes in which I have stored my most recent acquisitions: grubs, pupae and coc.o.o.ns of all kinds, whose evolution I wished to study.

Whenever these receptacles have an atom of free s.p.a.ce, they claim the right to build there, whereas I formally oppose the claim. I hardly reckoned on such a success, which obliges me to put some order into the invasion with which I am threatened. I seal up the locks, I shut my boxes, I close my various receptacles for old nests, in short I remove from the building-yard any retreat of which I do not approve. And now, O my Osmiae, I leave you a free field!