ARV? FOODS MANUFACTURED BY OTHERS?-?CARCASSES OF ANIMALS STORED UP?-?PROVISION OF PARALYSED LIVING ANIMALS?-?THE CAUSE OF THE PARALYSIS?-?THE SURENESS OF INS

that will favour the healthy development of their descendants, we must not necessarily conclude that the species possess these instincts from the beginning. They are not to be regarded as mechanisms artfully wound up and functioning since the appearance of life on the earth with the same inevitable regularity. The qualities which we find in them were weak at first; they have developed in the course of ages, and have finally, by heredity, been impressed upon the creatures to manifest themselves by necessary acts from which there is no longer any escape. There is no need for surprise if we meet to-day, I do not say among all, but among a ve

ned species, acts at first imperfect, but designed, have become perfect and instinctive, we can at least find in space different deg

ggs, are contented to conceal them a little so that they may not become a too easy prey, and are altogether indifferent as to what may happen afterwards. As soon as they come out, the young obtain their own food from day to day; myriads are destroyed, and if the races remain so strong numerically it is because they are saved by the innumera

elaborate materials from their own organism and store them up in the form of milk to nourish the young. This fact is related to foresight, with a view to offspring, exact

of flowers, to some extent for themselves, but especially in order that their young may at the moment of appearance possess a food which will enable them to undergo their first metamorphosis sheltered from the inclemencies outside. These foo

y labours, and do not know how to execute them; but they do not intend that their young shall be the victims of m

g of the sexes brings death and life to the eggs at the same time. Henceforth fixed on this laying insect, the little Sitaris remain quiet, and have only to wait; their future is assured. The Anthophora has made her chambers, and with the greatest care has filled each of them with honey. Then in the midst she deposits an egg, which remains floating on the surface like a little boat; when her task is accomplished, the mother passes to a new cell to confide to it another of her descendants. During this time the parasite larva hastily descends the abdominal hairs and allows itself to fall on the egg of the Anthophora, to be then borne upon it as upon a raft; its fall must take place at the precise instant which will enable it to embark without falling into the honey, in which just now it would be glued fast, and perish. This series of circumstances results only in the introduction of a single Sitaris into a chamber; the moment which must be profited by is too short for many of them to seize. If the female Anthophora carries others hidden in her hairs, they are obliged to await a new hatching to let themselves glide off. Thus enclosed with the egg of the Anthophora and its provision of honey, the larva has no other rival to fear, and may alone utilise the whole store. This parasitism has to such an extent become a habit with the species, that the larva's organisation has become modified by it. At the moment when it falls into the cell it cannot feed on honey. It is indispensable for its development that it should first devour the egg on which it floats; it can at this period be nourished by no other food. In acting in this way it also frees itself from a voracious being who would require much food. This first repast lasts about eight days, at the end of which it undergoes a moult, takes another form, and begins to float on the honey, gradually devouring it, for at this stage it becomes able to assimilate honey. Slowly its development is completed, with extremely interesting details with which we need not now concern ourselves. The larva of Sitaris is then in conditions exceptionally favourable for growth; but, in spite of appearances, there is no reason for admiring the marvellous foresight and extraordinary sureness of in

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on; but as good parents they wish to save their larv? from it, as in a feeble condition these might suffer severely. They desire to lay up a carcass for their young alone, and with this object they bury it in the earth. The eggs also which will thus develop in the soil have more chance of escaping destruction by various insectivorous animals. If these diggers find a rat (Fig. 16) or a dead bird, three or four unite their efforts, glide beneath it, and dig with immense activity, kicking away with their hind legs the earth withdrawn from the hole. They do not pause, and their work soon perceptibly advances. The rat gradually sinks in the pit as it grows deeper. When they have the good fortune to find the earth soft they can sink the prey in less than two hours to a depth of thirty centimetres. At this level they stop, and throw back into the hole the earth they have dug out, carefully smoothing the hillock which covers the grave. Thus stored up, the carcass is ready to receive the Necropho

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and the way in which their various operations are adapted to circumstances; genuine

he has then to devote about three days' work to each of them, for there is much to do, as may be imagined. For each of these hiding-places the Sphex first pierces a horizontal gallery about two or three inches long; then she bends it obliquely so that it penetrates deeply into the earth, and it is again continued in this direction for about three inches. At the end of this passage three or four chambers are made, usually three; each of these is meant to receive one egg. The insect interrupts its mining task, not forming the three chambers consecutively; when the first is completed she provisions it?-?we shall soon see in what manner?-?and lays a

last long without slipping; but as they only have to last for a single season they possess sufficient resistance for the insect's purpose. The lar

nterrupts digging operations it is to fly on a hunting expedition. It soon returns with a cricket it has seized, holding it by one antenna which it turns round in its jaws. It is a heavy burden for the slender Sphex to bear. Sometimes on foot, dragging its burden after it, sometimes flying, and carryin

ad left its insect, but could not find it. It was naturally very perplexed, and examined the neighbourhood with extreme agitation, not knowing what had happened, and evidently regarding the whole affair as very extraordinary; at last it found the victim it was seeking. The cricket still preserved the same immobility; its executioner seized it by an antenna and drew it anew to the entrance of the hole. In the interior of the subterranean domain everything is in good order; the insect had just assured itself of the fact, and we should expect to see it enter with its prey; not at all, it entered alone, and only decided to introduce the prey after it had made a fresh inspection. This fact is surprising, and it is still more surprising that if the practical joke of removing the cricket is repeated several times in succession, the Sphex drags it anew every time to the entrance of the burrow and first descends alone; forty times over this experiment succeeded without the insect deciding to renounce the habitual man?uvre. Fabre insists on this fact, and rightly, for nothing should be neglected; he makes it a text to show how automatic instinct is, and how the acts which proceed from it are invariably regulated so as to succeed one another always in the same order. In their nature these acts are quite indistinguishable from intelligent acts; only the creature is not capable

blow were to reach the Sphex it would be disembowelled; but it avoids the blows skilfully without ceasing its own violent attack. At last the combat ends; the cricket is brought to earth, turned on to its back, and maintained in this position by the Sphex. Still on its guard, the latter seizes in its jaws one of the filaments which terminate the abdomen of the vanquished, placing its legs on the belly; with the two posterior legs it holds the head turned back so as to stretch the under side of the neck. The cricket is unable to move and the conqueror's sting wanders over the horny carapace seeking a joint, feeling for a soft place in which it can enter to give the finishing stroke. The dart a

n at the end of twenty-four or forty-eight hours if the dose has not been too strong. The cricket is in a similar condition; it neither eats nor breathes; being incapable also of movement, there is no vital expenditure; it remains in a sort of torpor, or latent life, awaiting the tragic fate that is reserved for it. When it has been deposited in the little mortuary chamber the Sphex lays an egg

e so automatic as we are sometimes led to believe, in accordance with facts which are perfectly accurate, we ought always to observe the following succession of acts: first, hollowing of the burrow; second, the chase; third, the blows of the dart; fourth, the different man?uvres for placing the victim in the sarcophagus. Now in the present case the insect had accomplished the first three series of actions, and had even begun the fourth; it ought next to drag the cricket into the burrow without listening to the recriminations which the latter had no business to make

ng out on the chase to fill it, it does not devote itself to the labour of digging until a successful expedition has already assured the victim. (Fig. 17.) Instead of attacking crickets it seeks a larger orthopter

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determined by physical circumstances. But these arguments have no bearing if we consider the method of procedure adopted by the Ammophila,74 a hymenopterous insect related to the preceding, which paralyses caterpillars. It is free in this case to insert its sting at any portion of the body; yet it knows how to turn over and arrange the captive so that the dart shall penetrate both times at two points where ganglia will be poi

ralysing the cockroach by stinging it on the nervous chain. These preliminary operations do not impede it, but it is embarrassed when it wishes to introduce through the entrance of its gallery an insect which is too large. It pulls at first as much as it can, but seeing the failure of its efforts it does not persevere in this attempt, and comes out to survey the situation. Decidedly the victim is too large and cannot pass through. The Chlorion begins by cutting off the elytra, which maintain it rigid and prevent it from being compressed. This done, it harnesses itself anew and re-

of the Sphex, and it would be superfluous to describe it. The only fact which I wish to mention, and which has been put out of doubt by the illustrious naturalist, is this: the Buprestis are paralysed, not dead; all the joints of the antenn? and legs remain flexible and the intestines in good condition. He was able to dissect some which had been in a state of le

to bring a new victim. This insect is scarcely more advanced than birds, who feed their young from day to day. And it is a great labour to re-open every time the gallery which leads to the nursery; on all these visits, in fact, the Bembex fills it up on leaving, and causes the disappearance of all revealing traces. It is obliged to take so much trouble, because it has not inherited from its ancestors the receipt for the paralysing sting; it throws itself without care on its victim, delivers a few chance blows, and kills it. Necessarily it cannot, under these conditions, lay up provisions for the future; they would corrupt, and the larv? would not be benefited; hence the obligation of frequently returning to the nest, and of a perpetual hunt to feed descendants whom nature has gi

pricked. Victims who have been taken from the interior of provision burrows can live for a long time in spite of their wounds; they cannot, therefore, have received venom by inoculation. The author already quoted believes that the Pompilius seizes its captive by the pedicle which unites the abdomen to the cephalothorax, and that it triturates this point between it