I at last began to suspect that this is first and foremost a question of sex. In many Bees and Wasps, indeed, the male and the female differ not only in certain details of internal or external structure—a point of view which does not affect the present problem—but also in length and bulk, which depend in a high degree on the quantity of food.

Let us consider in particular the Bee-eating Philanthus. Compared with the female, the male is a mere abortion. I find that he is only a third to half the size of the other sex, as far as I can judge by sight alone. To obtain exactly the respective quantities of substance, I should need delicate balances, capable of weighing down to a milligramme. My clumsy villager's scales, on which potatoes may be weighed to within a kilogramme or so, do not permit of this precision. I must therefore rely on the evidence of my sight alone, evidence, for that matter, which is amply sufficient in the present instance. Compared with his mate, the Mantis-hunting Tachytes is likewise a pigmy. We are quite astonished to see him pestering his giantess on the threshold of the burrows.

We observe differences no less pronounced of size—and consequently of volume, mass and weight—in the two sexes of many Osmiae. The differences are less emphatic, but are still on the same side, in the Cerceres, the Stizi, the Spheges, the Chalicodomae and many more. It is therefore the rule that the male is smaller than the female. There are of course some exceptions, though not many; and I am far from denying them. I will mention certain Anthidia where the male is the larger of the two. Nevertheless, in the great majority of cases the female has the advantage.

And this is as it should be. It is the mother, the mother alone, who laboriously digs underground galleries and chambers, kneads the plaster for coating the cells, builds the dwelling-house of cement and bits of grit, bores the wood and divides the burrow into storeys, cuts the disks of leaf which will be joined together to form honey-pots, works up the resin gathered in drops from the wounds in the pine-trees to build ceilings in the empty spiral of a Snail-shell, hunts the prey, paralyses it and drags it indoors, gathers the pollen-dust, prepares the honey in her crop, stores and mixes the paste. This severe labour, so imperious and so active, in which the insect's whole life is spent, manifestly demands a bodily strength which would be quite useless to the male, the amorous trifler. Thus, as a general rule, in the insects which carry on an industry the female is the stronger sex.

Does this pre-eminence imply more abundant provisions during the larval stage, when the insect is acquiring the physical growth which it will not exceed in its future development? Simple reflection supplies the answer: yes, the aggregate growth has its equivalent in the aggregate provisions. Though so slight a creature as the male Philanthus finds a ration of two Bees sufficient for his needs, the female, twice or thrice as bulky, will consume three to six at least. If the male Tachytes requires three Mantes, his consort's meal will demand a batch of something like ten. With her comparative corpulence, the female Osmia will need a heap of paste twice or thrice as great as that of her brother, the male. All this is obvious; the animal cannot make much out of little.

Despite this evidence, I was anxious to enquire whether the reality corresponded with the previsions of the most elementary logic. Instances are not unknown in which the most sagacious deductions have been found to disagree with the facts. During the last few years, therefore, I have profited by my winter leisure to collect, from spots noted as favourable during the working-season, a few handfuls of cocoons of various Digger-wasps, notably of the Bee-eating Philanthus, who has just furnished us with an inventory of provisions. Surrounding these cocoons and thrust against the wall of the cell were the remnants of the victuals—wings, corselets, heads, wing-cases—a count of which enabled me to determine how many head of game had been provided for the larva, now enclosed in its silken abode. I thus obtained the correct list of provisions for each of the huntress' cocoons. On the other hand, I estimated the quantities of honey, or rather I gauged the receptacles, the cells, whose capacity is proportionate to the mass of the provisions stored. After making these preparations, registering the cells, cocoons and rations and putting all my figures in order, I had only to wait for the hatching-season to determine the sex.

Well, I found that logic and experiment were in perfect agreement. The Philanthus-cocoons with two Bees gave me males, always males; those with a larger ration gave me females. From the Tachytes-cocoons with double or treble that ration I obtained females. When fed upon four or five Nut-weevils, the Sand Cerceris was a male; when fed upon eight or ten, a female. In short, abundant provisions and spacious cells yield females; scanty provisions and narrow cells yield males. This is a law upon which I may henceforth rely.

At the stage which we have now reached a question arises, a question of major importance, touching the most nebulous aspect of embryogeny. How is it that the larva of the Philanthus, to take a particular case, receives three to five Bees from its mother when it is to become a female and not more than two when it is to become a male? Here the various head of game are identical in size, in flavour, in nutritive properties. The food-value is precisely in proportion to the number of items supplied, a helpful detail which eliminates the uncertainties wherein we might be left by the provision of game of different species and varying sizes. How is it, then, that a host of Bees and Wasps, of honey-gatherers as well as huntresses, store a larger or smaller quantity of victuals in their cells according as the nurselings are to become females or males?

The provisions are stored before the eggs are laid; and these provisions are measured by the needs of the sex of an egg still inside the mother's body. If the egg-laying were to precede the rationing, which occasionally takes place, as with the Odyneri (Cf. "The Hunting Wasps": chapters 2 and 8.—Translator's Note.), for example, we might imagine that the gravid mother enquires into the sex of the egg, recognizes it and stacks victuals accordingly. But, whether destined to become a male or a female, the egg is always the same; the differences—and I have no doubt that there are differences—are in the domain of the infinitely subtle, the mysterious, imperceptible even to the most practised embryogenist. What can a poor insect see—in the absolute darkness of its burrow, moreover—where science armed with optical instruments has not yet succeeded in seeing anything? And besides, even were it more discerning than we are in these genetic obscurities, its visual discernment would have nothing whereupon to practice. As I have said, the egg is laid only when the corresponding provisions are stored. The meal is prepared before the larva which is to eat it has come into the world. The supply is generously calculated by the needs of the coming creature; the dining-room is built large or small to contain a giant or a dwarf still germinating in the ovarian ducts. The mother, therefore, knows the sex of her egg beforehand.

A strange conclusion, which plays havoc with our current notions! The logic of the facts leads us to it directly. And yet it seems so absurd that, before accepting it, we seek to escape the predicament by another absurdity. We wonder whether the quantity of food may not decide the fate of the egg, originally sexless. Given more food and more room, the egg would become a female; given less food and less room, it would become a male. The mother, obeying her instincts, would store more food in this case and less in that; she would build now a large and now a small cell; and the future of the egg would be determined by the conditions of food and shelter.

Let us make every test, every experiment, down to the absurd: the crude absurdity of the moment has sometimes proved to be the truth of the morrow. Besides, the well-known story of the Hive-bee should make us wary of rejecting paradoxical suppositions. Is it not by increasing the size of the cell, by modifying the quality and quantity of the food, that the population of a hive transforms a worker larva into a female or royal larva? It is true that the sex remains the same, since the workers are only incompletely developed females. The change is none the less miraculous, so much so that it is almost lawful to enquire whether the transformation may not go further, turning a male, that poor abortion, into a sturdy female by means of a plentiful diet. Let us therefore resort to experiment.

I have at hand some long bits of reed in the hollow of which an Osmia, the Three-horned Osmia, has stacked her cells, bounded by earthen partitions. I have related elsewhere (Cf. "Bramble-bees and Others": chapters 2 to 5.—Translator's Note.) how I obtain as many of these nests as I could wish for. When the reed is split lengthwise, the cells come into view, together with their provisions, the egg lying on the paste, or even the budding larva. Observations multiplied ad nauseam have taught me where to find the males and where the females in this apiary. The males occupy the fore-part of the reed, the end next to the opening; the females are at the bottom, next to the knot which serves as a natural stopper to the channel. For the rest, the quantity of the provisions in itself points to the sex: for the females it is twice or thrice as great as for the males.

In the scantily-provided cells, I double or treble the ration with food taken from other cells; in the cells which are plentifully supplied, I reduce the portion to a half or a third. Controls are left: that is to say, some cells remain untouched, with their provisions as I found them, both in the part which is abundantly provided and in that which is more meagrely rationed. The two halves of the reed are then restored to their original position and firmly bound with a few turns of wire. We shall see, when the time comes, whether these changes increasing or decreasing the victuals have determined the sex.

Here is the result: the cells which at first were sparingly provided, but whose supplies were doubled or trebled by my artifice, contain males, as foretold by the original amount of victuals. The surplus which I added has not completely disappeared, far from it: the larva has had more than it needed for its evolution as a male; and, being unable to consume the whole of its copious provisions, it has spun its cocoon in the midst of the remaining pollen-dust. These males, so richly supplied, are of handsome but not exaggerated proportions; you can see that the additional food has profited them to some small extent.

The cells with abundant provisions, reduced to a half or a third by my intervention, contain cocoons as small as the male cocoons, pale, translucent and limp, whereas the normal cocoons are dark-brown, opaque and firm to the touch. These, we perceive at once, are the work of starved, anaemic weavers, who, failing to satisfy their appetite and having eaten the last grain of pollen, have, before dying, done their best with their poor little drop of silk. Those cocoons which correspond with the smallest allowance of food contain only a dead and shrivelled larva; others, in whose case the provisions were less markedly decreased, contain females in the adult form, but of very diminutive size, comparable with that of the males, or even smaller. As for the controls which I was careful to leave, they confirm the fact that I had males in the part near the orifice of the reed and females in the part near the knot closing the channel.

Is this enough to dispose of the very improbable supposition that the determination of the sex depends on the quantity of food? Strictly speaking, there is still one door open to doubt. It may be said that experiment, with its artifices, does not succeed in realizing the delicate natural conditions. To make short work of all objections, I cannot do better than have recourse to facts in which the experimenter's hand has not intervened. The parasites will supply us with these facts; they will show us how alien the quantity and even the quality of the food are from either specific or sexual characters. The subject of enquiry thus becomes double, instead of single as it was when I plundered one cell in my split reeds to enrich another. Let us follow this double current for a little while.

An Ammophila, the Silky Ammophila (Cf. "The Hunting Wasps": chapter 13.—Translator's Note.), which feeds on Looper caterpillars (Known also as Measuring-worms, Inchworms, Spanworms and Surveyors: the caterpillars of the Geometrid Moths.—Translator's Note.), has just been reared in my refectory on Spiders. Replete to the regulation point, it spins its cocoon. What will emerge from this? If the reader expects to see any modifications, caused by a diet which the species, left to itself, had never effected, let him be undeceived and that quickly. The Ammophila fed on Spiders is precisely the same as the Ammophila fed on caterpillars, just as man fed on rice is the same as man fed on wheat. In vain I pass my lens over the product of my art: I cannot distinguish it from the natural product; and I defy the most meticulous entomologist to perceive any difference between the two. It is the same with my other boarders who have had their diet altered.

I see the objection coming. The differences may be inappreciable, for my experiments touch only a first rung of the ladder. What would happen if the ladder were prolonged, if the offspring of the Ammophila fed on Spiders were given the same food generation after generation? These differences, at first imperceptible, might become accentuated until they grew into distinct specific characters; the habits and instincts might also change; and in the end the caterpillar-huntress might become a Spider-huntress, with a shape of her own. A species would be created, for, among the factors at work in the transformation of animals, the most important of all is incontestably the type of food, the nature of the thing wherewith the animal builds itself. All this is much more important than the trivialities which Darwin relies upon.

To create a species is magnificent in theory, so that we find ourselves regretting that the experimenter is not able to continue the attempt. But, once the Ammophila has flown out of the laboratory to slake her thirst at the flowers in the neighbourhood, just to try to find her again and induce her to entrust you with her eggs, which you would rear in the refectory, to increase the taste for Spiders from generation to generation! Merely to dream of it were madness. Shall we, in our helplessness, admit ourselves beaten by the evolutionary effects of diet? Not a bit of it! One experiment—and you could not wish for a more decisive—is continually in progress, apart from all artifices, on an enormous scale. It is brought to our notice by the parasites.

They must, we are told, have acquired the habit of living on others in order to save themselves work and to lead an easier life. The poor wretches have made a sorry blunder. Their life is of the hardest. If a few establish themselves comfortably, dearth and dire famine await most of the rest. There are some—look at certain of the Oil-beetles—exposed to so many chances of destruction that, to save one, they are obliged to procreate a thousand. They seldom enjoy a free meal. Some stray into the houses of hosts whose victuals do not suit them; others find only a ration quite insufficient for their needs; others—and these are very numerous—find nothing at all. What misadventures, what disappointments do these needy creatures suffer, unaccustomed as they are to work! Let me relate some of their misfortunes, gleaned at random.

The Girdled Dioxys (D. cincta) loves the ample honey-stores of the Chalicodoma of the Pebbles. There she finds abundant food, so abundant that she cannot eat it all. I have already passed censure on this waste. (Cf. "The Mason-bees": chapter 10.—Translator's Note.) Now a little Osmia (O. cyanoxantha, Perez) makes her nest in the Mason's deserted cells; and this Bee, a victim of her ill-omened dwelling, also harbours the Dioxys. This is a manifest error on the parasite's part. The nest of the Chalicodoma, the hemisphere of mortar on its pebble, is what she is looking for, to confide her eggs to it. But the nest is now occupied by a stranger, by the Osmia, a circumstance unknown to the Dioxys, who comes stealing up to lay her egg in the mother's absence. The dome is familiar to her. She could not know it better if she had built it herself. Here she was born; here is what her family wants. Moreover, there is nothing to arouse her suspicions: the outside of the home has not changed its appearance in any respect; the stopper of gravel and green putty, which later will form a violent contrast with its white front, is not yet constructed. She goes in and sees a heap of honey. To her thinking this can be nothing but the Chalicodoma's portion. We ourselves would be beguiled, in the Osmia's absence. She lays her eggs in this deceptive cell.

Her mistake, which is easy to understand, does not in any way detract from her great talents as a parasite, but it is a serious matter for the future larva. The Osmia, in fact, in view of her small dimensions, collects but a very scanty store of food: a little loaf of pollen and honey, hardly the size of an average pea. Such a ration is insufficient for the Dioxys. I have described her as a waster of food when her larva is established, according to custom, in the cell of the Mason-bee. This description no longer applies; not in the very least. Inadvertently straying to the Osmia's table, the larva has no excuse for turning up its nose; it does not leave part of the food to go bad; it eats up the lot without having had enough.

This famine-stricken refectory can give us nothing but an abortion. As a matter of fact, the Dioxys subjected to this niggardly test does not die, for the parasite must have a tough constitution to enable it to face the disastrous hazards which lie in wait for it; but it attains barely half its ordinary dimensions, which means one-eighth of its normal bulk. To see it thus diminished, we are surprised at its tenacious vitality, which enables it to reach the adult form in spite of the extreme deficiency of food. Meanwhile, this adult is still the Dioxys; there is no change of any kind in her shape or colouring. Moreover, the two sexes are represented; this family of pigmies has its males and females. Dearth and the farinaceous mess in the Osmia's cell has had no more influence over species or sex than abundance and flowing honey in the Chalicodoma's home.

The same may be said of the Spotted Sapyga (S. punctata (A parasitic Wasp. Cf. "The Mason-bees": chapters 9 and 10.—Translator's Note.)), which, a parasite of the Three-pronged Osmia, a denizen of the bramble, and of the Golden Osmia, an occupant of empty Snail-shells, strays into the house of the Tiny Osmia (O. parvula (This bee makes her home in the brambles. Cf. "Bramble-dwellers and Others": chapters 2 and 3.—Translator's Note.)), where, for lack of sufficient food, it does not attain half its normal size.

A Leucopsis (Cf. "The Mason-bees": chapter 11.—Translator's Note.) inserts her eggs through the cement wall of our three Chalicodomae. I know her under two names. When she comes from the Chalicodoma of the Pebbles or Walls, whose opulent larva saturates her with food, she deserves by her large size the name of Leucopsis gigas, which Fabricius bestows upon her; when she comes from the Chalicodoma of the Sheds, she deserves no more than the name of L. grandis, which is all that Klug grants her. With a smaller ration "the giant" is to some degree diminished and becomes no more than "the large." When she comes from the Chalicodoma of the Shrubs, she is smaller still; and, if some nomenclator were to seek to describe her, she would no longer deserve to be called more than middling. From dimension 2 she has descended to dimension 1 without ceasing to be the same insect, despite the change of diet; and at the same time both sexes are present in the three nurselings, despite the variation in the quantity of victuals.

I obtain Anthrax sinuata ("The Mason-bees": chapters 8, 10 and 11.—Translator's Note.) from various bees' nests. When she issues from the cocoons of the Three-horned Osmia, especially the female cocoons, she attains the greatest development that I know of. When she issues from the cocoons of the Blue Osmia (O. cyanea, KIRB.), she is sometimes hardly one-third the length which the other Osmia gives her. And we still have the two sexes—that goes without saying—and still identically the same species.

Two Anthidia, working in resin, A. septemdentatum, LATR., and A. bellicosum, LEP. (For these Resin-bees, cf. "Bramble-bees and Others": chapter 10.—Translator's Note.), establish their domicile in old Snail-shells. The second harbours the Burnt Zonitis (Z. proeusta (Cf. "The Glow-worm and Other Beetles": chapter 6.—Translator's Note.)). Amply nourished this Meloe then acquires her normal size, the size in which she usually figures in the collections. A like prosperity awaits her when she usurps the provisions of Megachile sericans. (For this Bee, the Silky Leaf-cutter, cf. "Bramble-bees and Others": chapter 8.—Translator's Note.) But the imprudent creature sometimes allows itself to be carried away to the meagre table of the smallest of our Anthidia (A. scapulare, LATR. (A Cotton-bee, cf. idem: chapter 9.—Translator's Note.)), who makes her nests in dry bramble-stems. The scanty fare makes a wretched dwarf of the offspring belonging to either sex, without depriving them of any of their racial features. We still see the Burnt Zonitis, with the distinctive sign of the species: the singed patch at the tip of the wing-cases.

And the other Meloidae—Cantharides, Cerocomae, Mylabres (For these Blister-beetles or Oil-beetles, cf. "The Glow-worm and Other Beetles": chapter 6.—Translator's Note.)—to what inequalities of size are they not subject, irrespective of sex! There are some—and they are numerous—whose dimensions fall to a half, a third, a quarter of the regular dimensions. Among these dwarfs, these misbegotten ones, these victims of atrophy, there are females as well as males; and their smallness by no means cools their amorous ardour. These needy creatures, I repeat, have a hard life of it. Whence do they come, these diminutive Beetles, if not from dining-rooms insufficiently supplied for their needs? Their parasitical habits expose them to harsh vicissitudes. No matter: in dearth as well as in abundance the two sexes appear and the specific features remain unchanged.

It is unnecessary to linger longer over this subject. The demonstration is completed. The parasites tell us that changes in the quantity and quality of food do not lead to any transformation of species. Fed upon the larva of the Three-horned Osmia or of the Blue Osmia, Anthrax sinuata, whether of handsome proportions or a dwarf, is still Anthrax sinuata; fed upon the allowance of the Anthidium of the empty Snail-shells, the Anthidium of the brambles, the Megachile or doubtless many others, the Burnt Zonitis is still the Burnt Zonitis. Yet variation of diet ought to be a very potential factor in the problem of progress towards another form. Is not the world of living creatures ruled by the stomach? And the value of this factor is unity, changing nothing in the product.

The same parasites tell us—and this is the chief object of my digression—that excess or deficiency of nutriment does not determine the sex. So we are once more confronted with the strange proposition, which is now more positive than ever, that the insect which amasses provisions in proportion to the needs of the egg about to be laid knows beforehand what the sex of this egg will be. Perhaps the reality is even more paradoxical still. I shall return to the subject after discussing the Osmiae, who are very weighty witnesses in this grave affair. (Cf. "Bramble-bees and Others": chapters 3 to 5. The student is recommended to read these three chapters in conjunction with the present chapter, to which they form a sequel, with that on the Osmiae (chapter 2 of the above volume) intervening.—Translator's Note.)



CHAPTER 10. THE BEE-EATING PHILANTHUS.

To meet among the Wasps, those eager lovers of flowers, a species that goes hunting more or less on its own account is certainly a notable event. That the larder of the grub should be provided with prey is natural enough; but that the provider, whose diet is honey, should herself make use of the captives is anything but easy to understand. We are quite astonished to see a nectar-drinker become a blood-drinker. But our astonishment ceases if we consider things more closely. The double method of feeding is more apparent than real: the crop which fills itself with sugary liquid does not gorge itself with game. The Odynerus, when digging into the body of her prey, does not touch the flesh, a fare absolutely scorned as contrary to her tastes; she satisfies herself with lapping up the defensive drop which the grub (The Larva of Chrysomela populi, the Poplar Leaf-beetle.—Translator's Note.) distils at the end of its intestine. This fluid no doubt represents to her some highly-flavoured beverage with which she seasons from time to time the staple diet fetched from the drinking-bar of the flowers, some appetizing condiment or perhaps—who knows?—some substitute for honey. Though the qualities of the delicacy escape me, I at least perceive that the Odynerus does not covet anything else. Once its jar is emptied, the larva is flung aside as worthless offal, a certain sign of a non-carnivorous appetite. Under these conditions, the persecutor of the Chrysomela ceases to surprise us by indulging in the crying abuse of a double diet.

We even begin to wonder whether other species may not be inclined to derive a direct advantage from the hunting imposed upon them for the maintenance of the family. The Odynerus' method of work, the splitting open of the anal still-room, is too far removed from the obvious procedure to have many imitators; it is a secondary detail and impracticable with a different kind of game. But there is sure to be a certain variety in the direct means of utilizing the capture. Why, for instance, when the victim paralysed by the sting contains a delicious broth in some part of its stomach, should the huntress scruple to violate her dying prey and force it to disgorge without injuring the quality of the provisions? There must be those who rob the dead, attracted not by the flesh but by the exquisite contents of the crop.

In point of fact, there are; and they are even numerous. We may mention in the first rank the Wasp that hunts Hive-bees, the Bee-eating Philanthus (P. apivorus, LATR.). I long suspected her of perpetrating these acts of brigandage on her own behalf, having often surprised her gluttonously licking the Bee's honey-smeared mouth; I had an inkling that she did not always hunt solely for the benefit of her larvae. The suspicion deserved to be confirmed by experiment. Also, I was engaged in another investigation, which might easily be conducted simultaneously with the one suggested: I wanted to study, with all the leisure of work done at home, the operating-methods employed by the different Hunting Wasps. I therefore made use, for the Philanthus, of the process of experimenting under glass which I roughly outlined when speaking of the Odynerus. It was even the Bee-huntress who gave me my first data in this direction. She responded to my wishes with such zeal that I believed myself to possess an unequalled means of observing again and again, even to excess, what is so difficult to achieve on the actual spot. Alas, the first-fruits of my acquaintance with the Philanthus promised me more than the future held in store for me! But we will not anticipate; and we will place the huntress and her game together under the bell-glass. I recommend this experiment to whoever would wish to see with what perfection in the art of attack and defence a Hunting Wasp wields the stiletto. There is no uncertainty here as to the result, there is no long wait: the moment when she catches sight of the prey in an attitude favourable to her designs, the bandit rushes forward and kills. I will describe how things happen.

I place under the bell-glass a Philanthus and two or three Hive-bees. The prisoners climb the glass wall, towards the light; they go up, come down again and try to get out; the vertical polished surface is to them a practicable floor. They soon quiet down; and the spoiler begins to notice her surroundings. The antennae are pointed forwards, enquiringly; the hind-legs are drawn up with a little quiver of greed in the tarsi; the head turns to right and left and follows the evolutions of the Bees against the glass. The miscreant's posture now becomes a striking piece of acting: you can read in it the fierce longings of the creature lying in ambush, the crafty waiting for the moment to commit the crime. The choice is made: the Philanthus pounces on her prey.

Turn by turn tumbling over and tumbled, the two insects roll upon the ground. The tumult soon abates; and the murderess prepares to strangle her capture. I see her adopt two methods. In the first, which is more usual than the other, the Bee is lying on her back; and the Philanthus, belly to belly with her, grips her with her six legs while snapping at her neck with her mandibles. The abdomen is now curved forward from behind, along the prostrate victim, feels with its tip, gropes about a little and ends by reaching the under part of the neck. The sting enters, lingers for a moment in the wound; and all is over. Without releasing her prey, which is still tightly clasped, the murderess restores her abdomen to its normal position and keeps it pressed against the Bee's.

In the second method, the Philanthus operates standing. Resting on her hind-legs and on the tips of her unfurled wings, she proudly occupies an erect attitude, with the Bee held facing her between her four front legs. To give the poor thing a position suited to receive the dagger-stroke, she turns her round and back again with the rough clumsiness of a child handling its doll. Her pose is magnificent to look at. Solidly planted on her sustaining tripod, the two hinder tarsi and the tips of the wings, she at last crooks her abdomen upwards and again stings the Bee under the chin. The originality of the Philanthus' posture at the moment of the murder surpasses the anything that I have hitherto seen.

The desire for knowledge in natural history has its cruel side. To learn precisely the point attacked by the sting and to make myself thoroughly acquainted with the horrible talent of the murderess, I have investigated more assassinations under glass than I would dare to confess. Without a single exception, I have always seen the Bee stung in the throat. In the preparations for the final blow, the tip of the abdomen may well come to rest on this or that point of the thorax or abdomen; but it does not stop at any of these, nor is the sting unsheathed, as can readily be ascertained. Indeed, once the contest is opened, the Philanthus becomes so entirely absorbed in her operation that I can remove the cover and follow every vicissitude of the tragedy with my pocket-lens.

After recognizing the invariable position of the wound, I bend back and open the articulation of the head. I see under the Bee's chin a white spot, measuring hardly a twenty-fifth of an inch square, where the horny integuments are lacking and the delicate skin is shown uncovered. It is here, always here, in this tiny defect in the armour, that the sting enters. Why is this spot stabbed rather than another? Can it be the only vulnerable point, which would necessarily determine the thrust of the lancet? Should any one entertain so petty a thought, I advise him to open the articulation of the corselet, behind the first pair of legs. He will there see what I see: the bare skin, quite as fine as under the neck, but covering a much larger surface. The horny breast-plate offers no wider breach. If the Philanthus were guided in her operation solely by the question of vulnerability, it is here certainly that she ought to strike, instead of persistently seeking the narrow slit in the neck. The weapon would not need to hesitate and grope; it would obtain admission into the tissues off-hand. No, the stroke of the lancet is not forced upon it mechanically: the assassin scorns the large defect in the corselet and prefers the place under the chin, for eminently logical reasons which we will now attempt to unravel.

Immediately after the operation I take the Bee from the Philanthus. What strikes me is the sudden inertia of the antennae and the mouth-parts, organs which in the victims of most of the Hunting Wasps continue to move for so long a time. There are here not any of the signs of life to which I have been accustomed in my old studies of insect paralysis: the antennary threads waving slowly to and fro, the palpi quivering, the mandibles opening and closing for days, weeks and months on end. At most, the tarsi tremble for a minute or two; that constitutes the whole death-struggle. Complete immobility ensues. The inference drawn from this sudden inertia is inevitable: the Wasp has stabbed the cervical ganglia. Hence the immediate cessation of movement in all the organs of the head; hence the real instead of the apparent death of the Bee. The Philanthus is a butcher and not a paralyser.

This is one step gained. The murderess chooses the under part of the chin as the point attacked in order to strike the principal nerve-centres, the cephalic ganglia, and thus to do away with life at one blow. When this vital seat is poisoned by the toxin, death is instantaneous. Had the Philanthus' object been simply to effect paralysis, the suppression of locomotor movements, she would have driven her weapon into the flaw in the corselet, as the Cerceres do with the Weevils, who are much more powerfully armoured than the Bee. But her intention is to kill outright, as we shall see presently; she wants a corpse, not a paralytic patient. This being so, we must agree that her operating-method is supremely well-inspired: our human murderers could achieve nothing more thorough or immediate.

We must also agree that her attitude when attacking, an attitude very different from that of the paralysers, is infallible in its death-dealing efficacy. Whether she deliver her thrust lying on the ground or standing erect, she holds the Bee in front of her, breast to breast, head to head. In this posture all that she need do is to curve her abdomen in order to reach the gap in the neck and plunge the sting with an upward slant into her captive's head. Suppose the two insects to be gripping each other in the reverse attitude, imagine the dirk to slant slightly in the opposite direction; the results would be absolutely different and the sting, driven downwards, would pierce the first thoracic ganglion and produce merely partial paralysis. What skill, to sacrifice a wretched Bee! In what fencing-school was the slayer taught her terrible upward blow under the chin?

If she learnt it, how is it that her victim, such a past mistress in architecture, such an adept in socialistic polity, has so far learnt no corresponding trick to serve in her own defence? She is as powerful as her executioner; like the other, she carries a rapier, an even more formidable one and more painful, at least to my fingers. For centuries and centuries the Philanthus has been storing her away in her cellars; and the poor innocent meekly submits, without being taught by the annual extermination of her race how to deliver herself from the aggressor by a well-aimed thrust. I despair of ever understanding how the assailant has acquired her talent for inflicting sudden death, when the assailed, who is better-armed and quite as strong, wields her dagger anyhow and therefore ineffectively. If the one has learnt by prolonged practice in attack, the other should also have learnt by prolonged practice in defence, for attack and defence possess a like merit in the fight for life. Among the theorists of the day, is there one clear-sighted enough to solve the riddle for us?

If so, I will take the opportunity of putting to him a second problem that puzzles me: the carelessness, nay, more, the stupidity of the Bee in the presence of the Philanthus. You would be inclined to think that the victim of persecution, learning gradually from the misfortunes suffered by her family, would show distress at the ravisher's approach and at least attempt to escape. In my cages I see nothing of the sort. Once the first excitement due to incarceration under the bell-glass or the wire-gauze cover has passed, the Bee seems hardly to trouble about her formidable neighbour. I see one side by side with the Philanthus on the same honeyed thistle-head: assassin and future victim are drinking from the same flask. I see some one who comes heedlessly to enquire who that stranger can be, crouching in wait on the table. When the spoiler makes her rush, it is usually at a Bee who meets her half-way, and, so to speak, flings herself into her clutches, either thoughtlessly or out of curiosity. There is no wild terror, no sign of anxiety, no tendency to make off. How comes it that the experience of the ages, that experience which, we are told, teaches the animal so many things, has not taught the Bee the first element of apiarian wisdom: a deep-seated horror of the Philanthus? Can the poor wretch take comfort by relying on her trusty dagger? But she yields to none in her ignorance of fencing; she stabs without method, at random. However, let us watch her at the supreme moment of the killing.

When the ravisher makes play with her sting, the Bee does the same with hers and furiously. I see the needle now moving this way or that way in space, now slipping, violently curved, along the murderess' convex surface. These sword-thrusts have no serious results. The manner in which the two combatants are at grips has this effect, that the Philanthus' abdomen is inside and the Bee's outside. The latter's sting therefore finds under its point only the dorsal surface of the foe, a convex, slippery surface and so well armoured as to be almost invulnerable. There is here no breach into which the weapon can slip by accident; and so the operation is conducted with absolute surgical safety, notwithstanding the indignant protests of the patient.

After the fatal stroke has been administered, the murderess remains for a long time belly to belly with the dead, for reasons which we shall shortly perceive. There may now be some danger for the Philanthus. The attitude of attack and defence is abandoned; and the ventral surface, more vulnerable than the other, is within reach of the sting. Now the deceased still retains the reflex use of her weapon for a few minutes, as I learnt to my cost. Having taken the Bee too early from the bandit and handling her without suspecting any risk, I received a most downright sting. Then how does the Philanthus, in her long contact with the butchered Bee, manage to protect herself against that lancet, which is bent upon avenging the murder? Is there any chance of a commutation of the death-penalty? Can an accident ever happen in the Bee's favour? Perhaps.

One incident strengthens my faith in this perhaps. I had placed four Bees and as many Eristales under the bell-glass at the same time, with the object of estimating the Philanthus' entomological knowledge in the matter of the distinction of species. Reciprocal quarrels break out in the mixed colony. Suddenly, in the midst of the fray, the killer is killed. She tumbles over on her back, she waves her legs; she is dead. Who struck the blow? It was certainly not the excitable but pacific Drone-fly; it was one of the Bees, who struck home by accident during the thick of the fight. Where and how? I cannot tell. The incident occurs only once in my notes, but it throws a light upon the question. The Bee is capable of withstanding her adversary; she can then and there slay her would-be slayer with a thrust of the sting. That she does not defend herself to better purpose, when she falls into her enemy's clutches, is due to her ignorance of fencing and not to the weakness of her weapon. And here again arises, more insistently than before, the question which I asked above: how is it that the Philanthus has learnt for offensive what the Bee has not learnt for defensive purposes? I see but one answer to the difficulty: the one knows without having learnt; the other does not know because she is incapable of learning.

Let us now consider the motives that induce the Philanthus to kill her Bee instead of paralysing her. When the crime has been perpetrated, she manipulates her dead victim without letting go of it for a moment, holding its belly pressed against her own six legs. I see her recklessly, very recklessly, rooting with her mandibles in the articulation of the neck, sometimes also in the larger articulation of the corselet, behind the first pair of legs, an articulation of whose delicate membrane she is perfectly well aware, even though, when using her sting, she did not take advantage of this point, which is the most readily accessible of all. I see her rough-handling the Bee's belly, squeezing it against her own abdomen, crushing it in the press. The recklessness of the treatment is striking; it shows that there is no need for keeping up precautions. The Bee is a corpse; and a little hustling here and there will not deteriorate its quality, provided there be no effusion of blood. In point of fact, however rough the handling, I fail to discover the slightest wound.

These various manipulations, especially the squeezing of the neck, at once bring about the desired results: the honey in the crop mounts to the Bee's throat. I see the tiny drops spurt out, lapped up by the glutton as soon as they appear. The bandit greedily, over and over again, takes the dead insect's lolling, sugared tongue into her mouth; then she once more digs into the neck and thorax, subjecting the honey-bag to the renewed pressure of her abdomen. The syrup comes and is instantly lapped up and lapped up again. In this way the contents of the crop are exhausted in small mouthfuls, yielded one at a time. This odious meal at the expense of a corpse's stomach is taken in a sybaritic attitude; the Philanthus lies on her side with the Bee between her legs. The atrocious banquet sometimes lasts for half an hour or longer. At last the drained Bee is discarded, not without regret, it seems, for from time to time I see the manipulation renewed. After taking a turn round the top of the bell-jar, the robber of the dead returns to her prey and squeezes it, licking its mouth until the last trace of honey has disappeared.

This frenzied passion of the Philanthus for the Bee's syrup is declared in yet another fashion. When the first victim has been sucked dry, I slip under the glass a second victim, which is promptly stabbed under the chin and then subjected to pressure to extract the honey. A third follows and undergoes the same fate without satisfying the bandit. I offer a fourth and a fifth. They are all accepted. My notes mention one Philanthus who in front of my eyes sacrificed six Bees in succession and squeezed out their crops in the regulation manner. The slaughter came to an end not because the glutton was sated but because my functions as a purveyor were becoming rather difficult: the dry month of August causes the insects to avoid my harmas, which at this season is denuded of flowers. Six crops emptied of their honey: what an orgy! And even then the ravenous creature would very likely not have scorned a copious additional course, had I possessed the means of supplying it!

There is no reason to regret this break in the service; the little that I have said is more than enough to prove the singular characteristics of the Bee-slayer. I am far from denying that the Philanthus has an honest means of earning her livelihood; I find her working on the flowers as assiduously as the other Wasps, peacefully drawing her honeyed beakers. The males even, possessing no lancet, know no other manner of refreshment. The mothers, without neglecting the table d'hote of the flowers, support themselves by brigandage as well. We are told of the Skua, that pirate of the seas, that he swoops down upon the fishing birds, at the moment when they rise from the water with a capture. With a blow of the beak delivered in the pit of the stomach he makes them give up their prey, which is caught by the robber in mid-air. The despoiled bird at least gets off with nothing worse than a contusion at the base of the throat. The Philanthus, a less scrupulous pirate, pounces on the Bee, stabs her to death and makes her disgorge in order to feed upon her honey.

I say feed and I do not withdraw the word. To support my statement I have better reasons than those set forth above. In the cages in which various Hunting Wasps, whose stratagems of war I am engaged in studying, are waiting till I have procured the desired prey—not always an easy thing—I have planted a few flower-spikes, a thistle-head or two, on which are placed drops of honey renewed at need. Here my captives come to take their meals. With the Philanthus, the provision of honeyed flowers, though favourably received, is not indispensable. I have only to let a few live Bees into her cage from time to time. Half a dozen a day is about the proper allowance. With no other food than the syrup extracted from the slain, I keep my insects going for a fortnight or three weeks.

It is as plain as a pikestaff: outside my cages, when the opportunity offers, the Philanthus must also kill the Bee on her own account. The Odynerus asks nothing from the Chrysomela but a mere condiment, the aromatic juice of the rump; the other extracts from her victim an ample supplement to her victuals, the crop full of honey. What a hecatomb of Bees must not a colony of these freebooters make for their personal consumption, not to mention the stored provisions! I recommend the Philanthus to the signal vengeance of our Bee-masters.

Let us go no deeper into the first causes of the crime. Let us accept things as we know them for the moment, with their apparent or real atrocity. To feed herself, the Philanthus levies tribute on the Bee's crop. Having made sure of this, let us consider the bandit's method more closely. She does not paralyse her capture according to the rites customary among the Hunting Wasps; she kills it. Why kill it? If the eyes of our understanding be not closed, the need for sudden death is clear as daylight. The Philanthus proposes to obtain the honeyed broth without ripping up the Bee, a proceeding which would damage the game when it is hunted on behalf of the larvae, without resorting to the murderous extirpation of the crop. She must, by able handling, by skilful pressure, make the Bee disgorge, she must milk her, in a manner of speaking. Suppose the Bee stung behind the corselet and paralysed. That deprives her of her power of locomotion, but not of her vitality. The digestive organs in particular retain or very nearly retain their normal energy, as is proved by the frequent excretions that take place in the paralysed prey, so long as the intestine is not empty, as is proved above all by the victims of the Languedocian Sphex (Cf. "The Hunting Wasp": chapters 8 to 10.—Translator's Note.), those helpless creatures which I used to keep alive for forty days on end with a soup consisting of sugar and water. It is absurd to hope, without therapeutic means, without a special emetic, to coax a sound stomach into emptying its contents. The stomach of the Bee, who is jealous of her treasure, would lend itself to the process even less readily than another. When paralysed, the insect is inert; but there are always internal energies and organic forces which will not yield to the manipulator's pressure. The Philanthus will nibble at the throat and squeeze the sides in vain: the honey will not rise to the mouth so long as a vestige of life keeps the crop closed.

Things are different with a corpse. The tension is relaxed, the muscles become slack, the resistance of the stomach ceases and the bag of honey is emptied by the robber's vigorous pressure. You see, therefore, that the Philanthus is expressly obliged to inflict a sudden death, which will do away at once with the elasticity of the organs. Where is the lightning stroke to be delivered? The slayer knows better than we do, when she sticks the Bee under the chin. The cerebral ganglia are reached through the little hole in the neck and death ensues immediately.

The relation of these acts of brigandage cannot satisfy my distressing habit of following each reply obtained with a fresh question, until the granite wall of the unknowable rises before me. If the Philanthus is an expert in killing Bees and emptying crops swollen with honey, this cannot be merely an alimentary resource, especially when, in common with the others, she has the banqueting-hall of the flowers. I cannot accept her atrocious talent as inspired merely by the craving for a feast obtained at the expense of an empty stomach. Something certainly escapes us: the why and wherefore of that crop drained dry. A creditable motive may lie hidden behind the horrors which I have related. What is it?

Any one can understand the vagueness of the observer's mind when he first asks himself this question. The reader is entitled to be treated with consideration. I will spare him the recital of my suspicions, my gropings and my failures and will come straight to the results of my long investigation. Everything has its harmonious reason for existence. I am too fully persuaded of this to believe that the Philanthus pursues her habit of profaning corpses solely to satisfy her greed. What does the emptied crop portend? May it not be that...? Why, yes.... After all, who knows?... Let us try along these lines.

The mother's first care is the welfare of the family. So far, we have seen the Philanthus hunting only for her stomach's sake; let us watch her hunting as a mother. Nothing is easier than to distinguish the two performances. When the Wasp wants a few good mouthfuls and nothing more, she scornfully abandons the Bee after picking her crop. The Bee is to her a worthless remnant, which will shrivel where it lies and be dissected by the Ants. If, on the other hand, she wants to stow away the Bee as a provision for her larvae, she clasps her in her two intermediate legs and, walking on the other four, goes round and round the edge of the bell-glass, seeking for an outlet through which to fly off with her prey. When she recognizes the circular track as impossible, she climbs up the sides, this time holding the Bee by the antennae with her mandibles and clinging to the polished and perpendicular surface with her six feet. She reaches the top of the glass, stays for a little while in the hollow of the knob at the top, returns to the ground, resumes her circling and her climbing and does not decide to relinquish her Bee until she has stubbornly attempted every means of escape. This persistence on her part to retain her hold on the cumbrous burden tells us pretty plainly that the game would go straight to the cells if the Philanthus had her liberty.

Well, these Bees intended for the larvae are stung under the chin like the others; they are real corpses; they are manipulated, squeezed, drained of their honey exactly as the others are. In all these respects, there is no difference between the hunt conducted to provide food for the larvae and the hunt conducted merely to gratify the mother's appetite.

As the worries of captivity might well be the cause of a few anomalies in the insect's actions, I felt that I ought to enquire how things happen in the open. I lay in wait near some colonies of Philanthi, for longer perhaps than the question deserved, as it had already been settled by what had happened under glass. My tedious watches were rewarded from time to time. Most of the huntresses returned home immediately, with the Bee under their abdomen; some halted on the brambles hard by; and here I saw them squeezing the dead Bee and making her disgorge the honey, which was greedily lapped up. After these preliminaries the corpse was stored. Every doubt is therefore removed: the provisions of the larva are first carefully drained of their honey.

Since we are on the spot, let us prolong our stay and enquire into the customs of the Philanthus in a state of liberty. Serving dead prey, which goes bad in a few days, the Bee-huntress cannot adopt the method of certain insects which paralyse a number of separate heads of game and fill the cell with provisions, completing the ration before laying the egg. She needs the method of the Bembex, whose larva receives the necessary nourishment at intervals, as it grows larger. The facts confirm this deduction. Just now I described as tedious my watches near the colonies of the Philanthi. They were tedious in fact, even more so perhaps than those which the Bembeces used to inflict upon me in the old days. Outside the burrows of the Great Cerceris and other Weevil-lovers, outside those of the Yellow-winged Sphex, the Cricket-slayer, there is plenty of distraction, thanks to the bustling movement of the hamlet. The mother has hardly come back home before she goes out again, soon returning laden with a new prey and once more setting out upon the chase. The going and coming is repeated at close intervals until the warehouse is full.

The burrow of the Philanthus is far from showing any such animation, even in a populous colony. In vain were my watches prolonged for whole mornings or afternoons; it was but very rarely that the mother whom I had seen go in with a Bee came out again for a second expedition. Two captures at most by the same huntress was all that I was able to see during my long vigils. Feeding from day to day involves this deliberation. Once the family is supplied with a sufficient ration for the moment, the mother suspends her hunting-trips until further need arises and occupies herself with mining-work in her underground house. Cells are dug; I see the rubbish gradually pushed up to the surface. Beyond this there is not a sign of activity; it is as though the burrow were deserted.

The inspection of the site is no easy matter. The shaft descends to a depth of nearly three feet in a compact soil, either vertically or horizontally. The spade and pick, wielded by stronger but less expert hands than mine, are indispensable, for which reason the process of excavation is far from satisfying me fully. At the end of this long tunnel, which the straw which I use for sounding despairs of ever reaching, the cells are at last encountered, oval cavities with a horizontal major axis. Their number and general arrangement escape me.

Some of them already contain the cocoon, which is slender and semitransparent, like those of the Cerceris, and, like them, suggests the shape of certain homoeopathic phials, with oval bellies surmounted by a tapering neck. The cocoon is fastened to the end of the cell by the tip of this neck, which is darkened and hardened by the larva's excrement; it has no other support. It looks like a short club fixed by the end of the handle along the horizontal axis of the nest. Other cells contain the larva in a more or less advanced stage. The grub is munching the last morsel served to it, with the scraps of the victuals already consumed lying around it. Others lastly show me a Bee, one only, still untouched and bearing an egg laid on her breast. This is the first partial ration; the others will come as and when the grub grows larger. My anticipations are thus confirmed: following the example of the Bembeces, the Fly-killers, the Philanthus, the Bee-killer, lays her egg on the first piece warehoused and at intervals adds to her nurselings' repast.

The problem of the dead game is solved. There remains this other problem, one of incomparable interest: why are the Bees robbed of their honey before being served to the larvae? I have said and I say again that the killing and squeezing cannot be explained and excused simply by reference to the Philanthus' love of gormandizing. Robbing the worker of her booty is nothing out of the way: we see it daily; but cutting her throat in order to empty her stomach is going beyond a joke. And, as the Bees packed away in the cellar are squeezed dry just as much as the others, the thought occurs to my mind that a rumpsteak with jam is not to everybody's liking and that the game stuffed with honey might well be a distasteful or even unwholesome dish for the Philanthus' larvae. What will the grub do when, sated with blood and meat, it finds the Bee's honey-bag under its mandibles and especially when, nibbling at random, it rips open the crop and spoils its venison with syrup? Will it thrive on the mixture? Will the little ogre pass without repugnance from the gamy flavour of a carcase to the scent of flowers? A blunt statement or denial would serve no purpose. We must see. Let us see.

I rear some young Philanthus-grubs, already waxing large; but, instead of supplying them with the prey taken from the burrows, I give them game of my own catching, game replete with nectar from the rosemaries. My Bees, whom I kill by crushing their heads, are readily accepted; and I at first see nothing that corresponds with my suspicions. Then my nurselings languish, disdain their food, give a careless bite here and there and end by perishing, from the first to the last, beside their unfinished victuals. All my attempts miscarry: I do not once succeed in rearing my larvae to the stage of spinning the cocoon. And yet I am no novice in the functions of a foster-father. How many pupils have not passed through my hands and reached maturity in my old sardine-boxes as comfortably as in their natural burrows!

I will not draw rash conclusions from this check; I am conscientious enough to ascribe it to another cause. It may be that the atmosphere of my study and the dryness of the sand serving as a bed have had a bad effect on my charges, whose tender skins are accustomed to the warm moisture of the subsoil. Let us therefore try another expedient.

It is hardly feasible to decide positively by the methods which I have been following whether the honey is or is not repugnant to the grubs of the Philanthus. The first mouthfuls consist of meat; and then nothing particular occurs: it is the natural diet. The honey is met with later, when the morsel has been largely bitten into. If hesitation and lack of appetite are displayed at this stage, they come too late in the day to be conclusive: the larva's discomfort may be due to other, known or unknown, causes. The thing to do would be to offer the grub honey from the first, before artificial rearing has affected its appetite. It is useless, of course, to make the attempt with pure honey: no carnivorous creature would touch it, though it were starving. The jam-sandwich is the only device favourable to my plans, a meagre jam-sandwich, that is to say, the dead Bee lightly smeared or varnished with honey by means of a camel's-hair pencil.

Under these conditions, the problem is solved with the first few mouthfuls. The grub that has bitten into the honeyed prey draws back in disgust, hesitates a long time and then, urged by hunger, begins again, tries this side and that and ends by refusing to touch the dish. For a few days it pines away on top of its almost intact provisions; then it dies. All that are subjected to this regimen succumb. Do they merely perish of inanition in the presence of an unaccustomed food, which revolts their appetite, or are they poisoned by the small quantity of honey absorbed with the early mouthfuls? I cannot tell. The fact remains that, whether poisonous or repugnant, the Bee in the state of bread and jam is death to them; and this result explains, more clearly than the unfavourable circumstance of my former experiment, my failures with the Bee that had not been made to disgorge.

This refusal to touch the unwholesome or distasteful honey is connected with principles of nutrition which are too general to constitute a gastronomic peculiarity of the Philanthus. The other carnivorous larvae, at least in the order of the Hymenoptera, are bound to share it. Let us try. We will go to work as before. I unearth the larvae when they have attained a medium size, to avoid the weakness of infancy; I take away the natural provisions, smear the carcases separately with honey and, when this is done, restore its victuals to each of the grubs. I had to make a choice: not every subject was equally suited to my experiments. I must reject the larvae which are fed on one fat joint, such as those of the Scolia. The grub in fact attacks its prey at a determined point, dips its head and neck into the insect's body, rooting skilfully in the entrails to keep the game fresh until the end of the meal, and does not withdraw from the breach until the whole skin is emptied of its contents.

To make it let go with the object of coating the inside of the venison with honey had two drawbacks: I should be compromising the lingering vitality which saves the insect that is being devoured from going bad and, at the same time, I should be disturbing the delicate art of the devouring insect, which, if removed from the lode which it was working, would no longer be able to recover it or to distinguish between the lawful and the unlawful morsels. The larva of the Scolia, consuming its Cetonia-grub, has taught us all that we want to know on this subject in my earlier volume. (Chapters 2 to 5 of the present volume contain the whole of the matter referred to above.—Translator's Note.) The only acceptable larvae are those supplied with a heap of small insects, which are attacked without any special art, dismembered at random and eaten up quickly. Among these I have tested such as chance threw in my way: those of various Bembeces, all fed on Flies, those of the Palarus, whose bill of fare consists of a very large assortment of Hymenoptera; those of the Tarsal Tachytes, supplied with young Locusts; those of the Nest-building Odynerus, furnished with Chrysomela-grubs; those of the Sand Cerceris, endowed with a pinch of Weevils. A goodly variety, as you see, of consumers and consumed. Well, to all of these the seasoning with honey proved fatal. Whether poisoned or disgusted, they all died in a few days.

A strange result indeed! Honey, the nectar of the flowers, the sole diet of the Bee-tribe in both its forms and the sole resource of the Wasp in her a adult form, is to the larvae of the latter an object of insurmountable repugnance and probably a toxic dish. Even the transformation of the nymphosis surprises me less than this inversion of the appetite. What happens in the insect's stomach to make the adult seek passionately what the youngster refused lest it should die? This is not a question of organic debility unable to endure a too substantial, too hard, too highly spiced dish. The grub that gnaws the Cetonia-larva, that generous piece of butcher's meat; the glutton that crunches its batch of tough Locusts; the one that battens on nitrobenzine-flavoured game: they certainly own unfastidious gullets and accommodating stomachs. And these robust eaters allow themselves to die of hunger or digestive troubles because of a drop of syrup, the lightest food imaginable, suited to the weakness of extreme youth and a feast for the adult besides! What a gulf of obscurity in the stomach of a wretched grub!

These gastronomical researches called for a counterexperiment. The carnivorous larva is killed by honey. Conversely, is the mellivorous larva killed by animal food? Reservations are needful here, as in the previous tests. We should be courting a flat refusal if we offered a pinch of Locusts to the larvae of the Anthophora or the Osmia, for instance. (For both these Wild Bees cf. "Bramble-bees and Others": passim.—Translator's Note.) The honey-fed insect would not bite into it. There would be no use whatever in trying. We must find the equivalent of the jam-sandwich aforesaid; in other words, we must give the larva its natural fare with a mixture of animal food. The addition made by my artifices shall be albumen, as found in the egg of the Hen, albumen the isomer of fibrin, which is the essential factor in any form of prey.

On the other hand, the Three-horned Osmia lends herself most admirably to my plans, because of her dry honey, consisting for the greater part of floury pollen. I therefore knead this honey with albumen, graduating the dose until its weight largely exceeds that of the flour. In this way I obtain pastes of different degrees of consistency, but all firm enough to bear the larva without danger of immersion. With too fluid a mixture there would be a risk of death by drowning. Lastly I install a moderately-developed larva on each of my albuminous cakes.

The dish of my inventing does not incite dislike: far from it. The grubs attack it without hesitation and consume it with every appearance of the usual appetite. Things could not go better if the food had not been altered by my culinary recipes. Everything goes down, including the morsels in which I feared that I had overdone the addition of albumen. And—an even more important point—the Osmia-larvae fed in this manner attain their normal dimensions and spin their cocoons, from which adult insects issue in the following year. Notwithstanding the albuminous regimen, the cycle of the evolution is achieved without impediment.

What are we to conclude from all this? I feel greatly embarrassed. Omne vivum ex ovo, the physiologists tell us. Every animal is carnivorous, in its first beginnings: it is formed and nourished at the cost of its egg, in which albumen predominates. The highest, the mammal, adheres to this diet for a long time: it has its mother's milk, rich in casein, another isomer of albumen. The gramnivorous nestling is first fed on grubs, which are better adapted to the niceties of its stomach; many of the minutest new-born creatures, being at once left to their own devices, take to animal food. In this way the original method of nourishment is continued for all alike: the method which allows flesh to be made from flesh and blood from blood, with no chemical process beyond the simplest modification. At maturity, when the stomach has acquired its full strength, vegetable food is adopted, involving a more complicated chemistry but easier to obtain. Milk is followed by fodder, worms by seeds, the prey in the burrow by the nectar of the flowers.

This supplies a partial explanation of the twofold diet of the Hymenoptera with carnivorous larvae: meat first, honey next. But then the note of interrogation is shifted. It stood elsewhere; it now stands here. Why is the Osmia, who as a larva fares so well on albumen, fed on honey at the start? Why do the Bee-tribe receive a vegetable diet when the other members of the order receive an animal diet?

If I were a believer in evolution, I should say yes, by the fact of its germ, every animal is originally carnivorous. The insect in particular starts with albuminoid materials. Many larvae adhere to the egg-food, many adult insects do likewise. But the struggle to fill the belly, which after all is the struggle for life, demands something better than the precarious hazards of the chase. Man, at first a ravenous hunter after game, brought the flock into existence and turned shepherd to avoid a time of dearth. An even greater progress inspired him to scrape the earth and to sow seed, which assures him of a living. The evolution from scarcity to moderation and from moderation to plenty has led to the resources of husbandry.

The animals forestalled us this path of progress. The ancestors of the Philanthus, in the remote ages of the lacustrian tertiary formations, lived by prey in both the larval and the adult forms: they hunted for themselves as well as for the family. They did not confine themselves to emptying the Bee's crop, as their descendants do to this day: they devoured the deceased. From the beginning to the end they remained flesh-eaters. Later, fortunate innovators, whose race supplanted the laggards, discovered an inexhaustible nourishment, obtained without dangerous conflicts or laborious search: the sugary secretions of the flowers. The costly habit of living on prey, which does not favour large populations, was maintained for the feeble larvae; but the vigorous adult broke herself of it to lead an easier and more prosperous life. Thus, gradually, was formed the Philanthus of our day; thus was acquired the twofold diet of the various predatory insects our contemporaries.

The Bee has done better still: from the moment of leaving the egg she delivered herself completely from food-stuffs the acquisition of which depended on chance. She discovered honey, the grubs' food. Renouncing the chase for ever and becoming an agriculturalist pure and simple, the insect attains a degree of physical and moral prosperity which the predatory species are far from sharing. Hence the flourishing colonies of the Anthophorae, the Osmiae, the Eucerae (A genus of long-horned Burrowing Bees.—Translator's Note.), the Halicti and other honey-manufacturers, whereas the predatory insects work in isolation; hence the societies in which the Bee displays her wonderful tendencies, the supreme expression of instinct.

This is what I should say if I belonged to that school. It all forms a chain of very logical deductions and proffers itself with a certain air of likelihood which we should be glad to find in a host of evolutionist arguments put forward as irrefutable. Well, I will make a present of my deductive views, without regret, to whoever cares to have them: I don't believe one word of them; and I confess my profound ignorance of the origin of the twofold diet.

What I do understand more clearly, after all these investigations, is the tactics of the Philanthus. When witnessing her ferocious feasting, the real reason of which was unknown to me, I heaped the most ill-sounding epithets upon her, calling her a murderess, a bandit, a pirate, a robber of the dead. Ignorance is always evil-tongued; the man who does not know indulges in rude assertions and mischievous interpretations. Now that my eyes have been opened to the facts, I hasten to apologize and to restore the Philanthus to her place in my esteem. In draining the crops of her Bees the mother is performing the most praiseworthy of all actions: she is protecting her family against poison. If she happens to kill on her own account and to abandon the corpse after making it disgorge, I dare not reckon this against her as a crime. When the habit has been formed of emptying the Bee's crop with a good motive, there is a great temptation to do it again with no other excuse than hunger. Besides, who knows? Perhaps there is always at the back of her hunting some thought of game which might be useful for the larvae. Although not carried into effect, the intention excuses the deed.

I therefore withdraw my epithets in order to admire the insect's maternal logic and to hold it up to the admiration of others. The honey would be pernicious to the health of the larvae. How does the mother know that the syrup, a treat for her, is unwholesome for her young? To this question our science offers no reply. The honey, I say, would imperil the grubs' lives, The Bee must therefore first be made to disgorge. The disgorging must be effected without lacerating the victim, which the nurseling must receive in the fresh state; and the operation is impracticable on a paralysed insect because of the resistance of the stomach. The Bee must therefore be killed outright instead of being paralysed, or the honey will not be voided. Instantaneous death can be inflicted only by wounding the primordial centre of life. The sting must therefore aim at the cervical ganglia, the seat of innervation on which the rest of the organism depends. To reach them there is only one way, through the little gap in the throat. It is here therefore that the sting must be inserted; and it is here in fact that it is inserted, in a spot hardly as large as the twenty-fifth of an inch square. Suppress a single link of this compact chain, and the Bee-fed Philanthus becomes impossible.

That honey is fatal to carnivorous larvae is a fact which teems with consequences. Several Hunting Wasps feed their families upon Bees. These include, to my knowledge, the Crowned Philanthus (P. coronatus, FAB.), who lines her burrows with big Halicti; the Robber Philanthus (P. raptor, LEP.), who chases all the smaller-sized Halicti, suited to her own dimensions, indifferently; the Ornate Cerceris (C. ornata, FAB.), another passionate lover of Halicti; and the Palarus (P. flavipes, FAB.), who, with a curious eclecticism, stacks in her cells the greater part of the Hymenopteron clan that does not exceed her powers. What do these four huntresses and the others of similar habits do with their victims whose crops are more or less swollen with honey? They must follow the example of the Bee-eating Philanthus and make them disgorge, lest their family perish of a honeyed diet; they must manipulate the dead Bee, squeeze her and drain her dry. Everything goes to show it. I leave it to the future to display these dazzling proofs of my doctrine in their proper light.



CHAPTER 11. THE METHOD OF THE AMMOPHILAE.

(For these Sand-wasps, cf. "The Hunting Wasps": chapters 13 and 18 to 20.—Translator's Note.)

My readers may differ in appraising the comparative value of the trifling discoveries which entomology owes to my labours. The geologist, the recorder of forms, will prefer the hypermetamorphosis of the Oil-beetles (The chapter treating of this subject has not yet been translated into English and will appear in a later volume.—Translator's Note.), the development of the Anthrax (Cf. "The Life of the Fly": chapter 2.—Translator's Note.) or larval dimorphism; the embryogenist, searching into the mysteries of the egg, will have some esteem for my enquiries into the egg-laying habits of the Osmia (Cf. "Bramble-bees and Others": chapter 4.—Translator's Note.); the philosopher, racking his brain over the nature of instinct, will award the palm to the operations of the Hunting Wasps. I agree with the philosopher. Without hesitation, I would abandon all the rest of my entomological baggage for this discovery, which happens to be the earliest in date and that of which I have the fondest memories. Nowhere do I find a more brilliant, more lucid, more eloquent proof of the intuitive wisdom of instinct; nowhere does the theory of evolution suffer a more obstinate check.

Darwin, a true judge, made no mistake about it. (Charles Robert Darwin, born the 12th of February, 1809, at Shrewsbury, died at Down, in Kent, on the 19th of April, 1882. For an account of certain experiments which the author conducted on his behalf, cf. "The Mason-bees": chapter 4.—Translator's Note.) He greatly dreaded the problem of the instincts. My first results in particular left him very anxious. If he had known the tactics of the Hairy Ammophila, the Mantis-hunting Tachytes, the Bee-eating Philanthus, the Calicurgi and other marauders, his anxiety, I believe, would have ended in a frank admission that he was unable to squeeze instinct into the mould of his formula. Alas, the philosopher of Down quitted this world when the discussion, with experiments to support it, had barely begun: a method superior to any argument! The little that I had published at that time left him with still some hope of an explanation. In his eyes, instinct was always an acquired habit. The predatory Wasps killed their prey at first by stabbing it at random, here and there, in the softest parts. By degrees they found the spot where the sting was most effectual; and the habit once formed became a true instinct. Transitions from one method of operation to the other, intermediary changes, sufficed to bolster up these sweeping assertions. In a letter of the 16th of April, 1881, he asks G.J. Romanes to consider the problem:

"I do not know," he says "whether you will discuss in your book on the mind of animals any of the more complex and wonderful instincts. It is unsatisfactory work, as there can be no fossilised instincts, and the sole guide is their state in other members of the same order, and mere PROBABILITY.

"But if you do discuss any (and it will perhaps be expected of you), I should think that you could not select a better case than that of the sand-wasps which paralyse their prey as described by Fabre in his wonderful paper in the 'Anales des sciences naturelles,' and since amplified in his admirable 'Souvenirs...'"

I thank you, O illustrious master, for your eulogistic expressions, proving the keen interest which you took in my studies of instinct, no ungrateful task—far from it—when we tackle it as it should be tackled: from the front, with the aid of facts, and not from the flank, with the aid of arguments. Arguments are here out of place, if we wish to maintain our position in the light. Besides, where would they lead us? To evoking the instincts of bygone ages, which have not been preserved by fossilization? Any such appeal to the dim and distant past is quite unnecessary, if we wish for variations of instinct, leading by degrees, according to you, from one instinct to another; the present world offers us plenty.

Each operator has her particular method, her particular kind of game, her particular points of attack and tricks of fence; but in the midst of this variety of talents we observe, immutable and predominant, the perfect accordance of the surgery with the victim's organization and the larva's needs. The art of one will not explain the art of another, no less exact in the delicacy of its rules. Each operator has her own tactics, which tolerate no apprenticeship. The Ammophila, the Scolia, the Philanthus and the others all tell us the same thing: none can leave descendants if she be not from the outset the skilful paralyser or slayer that she is to-day. The "almost" is impracticable when the future of the race is at stake. What would have become of the first-born mammal but for its perfect instinct of suckling?

And then, to suppose the impossible: a Wasp discovers by chance the operative method which will be the saving attribute of her race. How are we to admit that this fortuitous act, to which the mother has vouchsafed no more attention than to her other less fortunate attempts, could leave a profound trace behind it and be faithfully transmitted by heredity? Is it not going beyond reason, going beyond the little that is known to us as certain, if we grant to atavism this strange power, of which our present world knows no instance? There is a good deal to be said for this point of view, my revered master! But, once more, arguments are here out of place; there is room only for facts, of which I will resume the recital.

Hitherto I had but one means of studying the operative methods of the spoilers: to surprise the Wasp in possession of her capture, to rob her of her prey and immediately to give her in exchange a similar prey, but a living one. This method of substitution is an excellent expedient. Its only defect—a very grave one—is that it subjects observation to very uncertain chances. There is little prospect of meeting the insect dragging its victim along; and, in the second place, should good fortune suddenly smile upon you, preoccupied as you are with other matters you have not the substitute at hand. If we provide ourselves with the necessary head of game in advance, the huntress is not there. We avoid one reef to founder on another. Moreover, these unlooked for observations, made sometimes on the public highway, the worst of laboratories, are only half-satisfactory. In the case of swiftly-enacted scenes, which it is not in our power to renew again and again until perfect conviction is reached, we always fear lest we may not have seen accurately, may not have seen everything.

A method which could be controlled at will would offer the best guarantees, above all if employed at home, under comfortable conditions, favourable to precision. I wished, therefore, to see my insects at work on the actual table at which I am writing their history. Here very few of their secrets would escape me. This wish of mine was an old one. As a beginner, I made some experiments under glass with the Great Cerceris (C. tuberculata) and the Yellow-winged Sphex. Neither of them responded to my desires. The refusal of each to attack respectively her Cleonus or her Cricket discouraged further progress in this direction. I was wrong to abandon my attempts so soon. Now, very long afterwards, the idea occurs to me to place under glass the Bee-eating Philanthus, whom I sometimes surprise in the open engaged in forcing a bee to disgorge her honey. The captive massacres her bees in such a spirited fashion that the old hope revives stronger than ever. I contemplate reviewing all the wielders of the stiletto and forcing each to reveal her tactics.

I was obliged to abate these ambitions considerably. I had some successes and many more failures. I will tell you of the former. My insect-cage is a spacious dome of wire-gauze resting on a bed of sand. Here I keep in reserve the captives of my hunting-expeditions. I feed them on honey, placed in little drops on spikes of lavender, on heads of thistle, or field eryngo, or globe-thistle, according to the season. Most of my prisoners do well on this diet and seem scarcely affected by their internment; others pine away and die in two or three days. These victims of despair nearly always throw me back, because of the difficulty of obtaining the necessary prey at short notice.

Indeed it entails no small trouble to secure in the nick of time the game demanded by the huntress who has recently fallen a captive to my net. As assistant-purveyors I have a few small schoolboys, who, released from the tedium of their declensions and conjugations, set out, on leaving the classroom, to inspect the greenswards and beat the bushes in the neighbourhood on my behalf. The gros sou, the penny-piece, if you please, stimulates their zeal; but with misadventurous results! What I need to-day is Crickets. The band sallies forth and returns with not a single Cricket, but numbers of Ephippigers, for which I asked the day before yesterday and which I no longer need, my Languedocian Sphex being dead. General surprise at this sudden change of market. My young scatterbrains find it hard to understand that the beast which was so precious two days ago is now of no value whatever. When, owing to the chances of my net, a renewed demand for the Ephippiger sets in, then they will bring me the Cricket, the despised Cricket.

Such a trade could never hold out if now and again my speculators were not encouraged by some success. At the moment when urgent necessity is sending up prices, one of them brings me a magnificent Gad-fly intended for the Bembex. For two hours, when the sun was at its height, he kept watch on the threshing-floor hard by, waiting for the blood-sucker, in order to catch him on the buttocks of the Mules which trot round and round trampling the corn. This gallant fellow shall have his gros sou and a slice of bread and jam as well. A second, no less fortunate, has found a fat Spider, the Epeira, for whom my Pompili are waiting. To the two sous of this fortunate youth I add a little picture for his missal. Thus are my purveyors kept going; and, after all, their help would be very inadequate if I did not take upon myself the main burden of these wearisome quests.

Once in possession of the requisite prey, I transfer the huntress from my warehouse, the wire-gauze cage, to a bell-glass varying in capacity from one to three or four litres (1 3/4 to 5 or 7 pints.—Translator's Note.), according to the size and habits of the combatants; I place the victim in the arena; I expose the bell-glass to the direct rays of the sun, without which condition the executioner as a rule declines to operate; I arm myself with patience and await events.

We will begin with the Hairy Ammophila, my neighbour. Year after year, when April comes, I see her in considerable numbers, very busy on the paths in my enclosure. Until June I see her digging her burrows and searching for the Grey Worm, to be placed in the meat-cellar. Her tactics are the most complex that I know and more than any other deserves to be thoroughly studied. To capture the cunning vivisector, to release her and catch her again I find an easy matter for the best part of a month; she works outside my door.

I have still to obtain the Grey Worm. This means a repetition of the disappointments which I had before, when, to find a caterpillar, I was obliged to watch the Ammophila while hunting and to be guided by her hints, as the truffle-hunter is guided by the scent of his Dog. A patient exploration of the harmas, one tuft of thyme after another, does not give me a single worm. My rivals in this search are finding their game at every moment; I cannot find it even once. Yet one more reason for bowing to the superiority of the insect in the management of her affairs. My band of schoolboys get to work in the surrounding fields. Nothing, always nothing! I in my turn explore the outer world; and for ten days the pursuit of a caterpillar torments me till I lose my power of sleep. Then, at last, victory! At the foot of a sunny wall, under the budding rosettes of the panicled centaury, I find a fair supply of the precious Grey Worm or its equivalent.

Behold the worm and the Ammophila face to face beneath the bell-glass. Usually the attack is prompt enough. The caterpillar is grabbed by the neck with the mandibles, wide, curved pincers capable of embracing the greater part of the living cylinder. The creature thus seized twists and turns and sometimes, with a blow of its tail, sends the assailant rolling to a distance. The latter is unconcerned and thrusts her sting thrice in rapid succession into the thorax, beginning with the third segment and ending with the first, where the weapon is driven home with greater determination than elsewhere.

The caterpillar is then released. The Ammophila stamps on the ground; with her quivering tarsi she taps the cardboard on which the bell-glass stands; she lies down flat, drags herself along, gets up again, flattens herself once more. The wings jerk convulsively. From time to time the insect places its mandibles and forehead on the ground, then rears high upon its hind-legs as though to turn head over heels. In all this I see a manifestation of delight. We rub our hands when rejoicing at a success; the Ammophila is celebrating her triumph over the monster in her own fashion. During this fit of delirious joy, what is the wounded caterpillar doing? It can no longer walk; but all the part behind the thorax struggles violently, curling and uncurling when the Ammophila sets a foot upon it. The mandibles open and shut menacingly.

SECOND ACT.—When the operation is resumed, the caterpillar is seized by the back. From front to rear, in order, all the segments are stung on the ventral surface, except the three operated on. All serious danger is averted by the stabs of the first act; therefore, the Wasp is now able to work upon her patient without the haste displayed at the outset. Deliberately and methodically she drives in her lancet, withdraws it, selects the spot, stabs it and begins again, passing from segment to segment, taking care, each time, to lay hold of the back a little more to the rear, in order to bring the segment to be paralysed within reach of the needle. For the second time, the caterpillar is released. It is absolutely inert, except the mandibles, which are still capable of biting.

THIRD ACT.—The Ammophila clasps the paralysed victim between her legs; with the hooks of her mandibles she seizes the back of its neck, at the base of the first thoracic segment. For nearly ten minutes she munches this weak spot, which lies close to the cerebral nerve-centres. The pincers squeeze suddenly but at intervals and methodically, as though the manipulator wished each time to judge of the effect produced; the squeezes are repeated until I am tired of trying to count them. When they cease, the caterpillar's mandibles are motionless. Then comes the transportation of the carcase, a detail which is not relevant in this place.

I have set forth the complete tragedy, as it is fairly often enacted, but not always. The insect is not a machine, unvarying in the effect of its mechanism; it is allowed a certain latitude, enabling it to cope with the eventualities of the moment. Any one expecting to see the incidents of the struggle unfolding themselves exactly as I have described will risk disappointment. Special instances occur—they are even numerous—which are more or less at variance with the general rule. It will be well to mention the more important, in order to put future observers on their guard.

Not infrequently the first act, that of paralysing the thorax, is restricted to two thrusts of the sting instead of three, or even to one, which is then delivered in the foremost segment. This, it would seem, from the persistency with which the Ammophila inflicts it, is the most important prick of all. Is it unreasonable to suppose that the operator, when she begins by pricking the thorax, intends to subdue her capture and to make it incapable of injuring her, or even of disturbing her when the moment comes for the delicate and protracted surgery of the second act? This idea seems to me highly admissible; and then, instead of three dagger-thrusts, why not two only, why not merely one, if this would suffice for the time being? The amount of vigour displayed by the caterpillar must be taken into consideration. Be this as it may, the segments spared in the first act are stabbed in the second. I have sometimes even seen the three thoracic segments stung twice over: at the beginning of the attack and again when the Wasp returned to her vanquished prey.

The Ammophila's triumphant transports beside her wounded and writhing victim are also subject to exceptions. Sometimes, without releasing its prey for a moment, the insect proceeds from the thorax to the next segments and completes its operation in a single spell. The joyous entr'acte does not take place; the convulsive movements of the wings and the acrobatic postures are suppressed.

The rule is paralysis of all the segments, however many, in regular order from front to back, including even the anal segment if this boast of legs. By a fairly frequent exception the last two or three segments are spared. Another exception, but a very rare one, of which I have observed only a single instance, consists in the inversion of the dagger-thrusts of the second act, the thrusts being delivered from back to front. The caterpillar is then seized by its hinder extremity; and the Ammophila, progressing towards the head, stings in reverse order, passing from the succeeding to the preceding segment, including the thorax already stabbed. This reversal of the usual tactics I am inclined to attribute to negligence on the insect's part. Negligence or not, the inverted method has the same final result as the direct method: the paralysis of all the segments.