More Hunting Wasps

e millimetre thick. (About.156 x.039 inch.-Translator's Note.) It is fixed, by its fore-end, upon the median line of the vic

tremity. A striking spectacle, that of the feeble creature, only this moment hatched, boring, for its first mouthful, into the paunch of its enormous prey, which lies stretched upon its

lator's Note.), whence follows that its bulk is six or seven hundred times as great as that of the newly-hatched grub of the Scolia. Here certainly is a quarry which, were it active and capable of wriggling and bitin

e it has dived under the skin of the exploited victim, does not come out again until the time arrives for spinning the cocoon, tapers off suddenly into a snake-like neck. This front part is moulded, so to speak, by the narrow entrance-hole made in the skin and henceforth retains its slender formation. As a matter of fact, a similar configuration recurs, in varying degrees, in the larvae of the Digger-wasps whose ration consists of a

l art in the manner of eating. The Cetonia-larva is a square meal in itself, one large dish, which has to retain a suitable freshness until the end. The young Scolia, therefore, must attack with discretion, at the unvarying point chosen by the mother on the ventral surface, for the entrance-hole is at the exact

rgans in its delicate folds. This again is a loss which the Cetonia can suffer without dying then and there. Now comes the turn of the muscular layer which lines the skin; now, that of the essential organs; now, that of the nerve-centres and the trachean network, whereupon the last gleam of light is extinguished and the Cetonia reduced to a mere bag, empty but intact, save for the entr

larva's body. The ruling feature in this scientific method of eating, which proceeds from the parts less to the parts more necessary to preserve a remnant of life, is no

nd this bag have the same characteristic look of fresh meat as had the grub before it was bitten into. Despite the persistent nibbling of the Scolia, life continues, holding at bay the inroads of putrefaction until the mandibles have given their la

ncision, through which I remove the mass of nerves whose remarkable structure we shall soon have occasion to study. The thing is done: the wound, which does not look serious, has left the creature a corpse, a real corpse. I lay my victim on a bed of moist earth, in a jar with a glass lid; in fact, I establish it in the same conditions as those of the

, which will provide it with wholesome food until the end. But it is clear that, if the Scolia were to set to work as I did, there would be nothing left, after the first few bites, but an actual corpse, discharging fluids which would be fatal to it within twenty-four hours. The mother, it is true, in order to assure the immobility of her prey, has injected the poison of her sting into the nerve-centres. Her operation cannot be compared with mine in any respect. She practises the method of the skilful physiologist who induces anaesthesi

he midst of their heap of Flies. The prey seized upon is broached on the back, the belly, the head, the thorax, indifferently. The larva munches a given spot, which it leaves to munch a second, passing to a third and a fourth, at the bidding of its changing whims. It seems to taste and select, by repeated trials, the mouthfuls most to its liking. Thus bitton at several

h turned putrid within twenty-four hours, I adopted an extreme case for the sake of greater clearness. The Scolia, taking its first bite, does not and cannot go to such lengths. Nevertheless it behooves us to enquire whether, in the consumption of the victuals, the initial point of attack i

little as possible. I succeed, by means of a little patience and repeated strokes with the tip of a paint-brush. I now turn the Cetonia-larva over, back uppermost, at the bottom of the little hollow made by pressing my finge

nothing. There are restless movements, nothing more. Hunger, I tell myself, will eventually induce it to bite. I am wrong. Next morning I find it more anxious than the day before and still groping about, without resolving to fix its man

ained a sturdy growth. Thus we see no lack of ability, but an obstinate refusal to nibble at a point which ought to be respected. Who knows? On this side perhaps the grub's dorsal vessel would be wounded, its heart, an organ indispensable to life. The fact remains that my attempts to make the grub tackle its victim from the b

I move the Scolia from its position, extract its head from the entrails of the Cetonia-larva and leave it to its own resources on its victim's belly. Betraying every symptom of uneasiness, the grub gropes, hesitates, casts about and does not insert its mandibles anywhere, though it is now the ventral surface which it is exploring. It would not display greater hesitation if placed on the back of the larva. I repeat, who knows? On this side it might perhaps injure th

ice; she fixes the egg to it; and the place where the opening is to be made is henceforth determined. It is here that the grub must bite: only here, never elsewhere. Its invin

its neck into it and little by little dives into the Cetonia's belly, so that the original state of affairs appears to be exactly restored. And yet its successful rearing is henceforth highly problematical. It is possible that the larva will prosper, complete its development and spin its cocoon; it is also poss

its usual courses by my interference, the grub, when replaced on the wound from which I extracted it, was unable to rediscover the lode at which it was working a few minutes earlier; it thrust its way at random into the victim's entrails; and a

ubstitute for this inert larva a similar larva, but one not paralysed, one very much alive. To ensure that it shall not double up and crush the grub, I confine myself to reducing it to helplessness, leaving it otherwise just as I extracted it from its burrow. I must also be careful of its legs and mandibles, the least touch of which would rip open the nurseling. With a few turns of the finest wire I fix it

ch hesitation, the young Scolia settles down to the wound made by my scalpel, which to the grub represents the wound whence I have just removed it. It thrusts its neck into the belly of its prey; and for a couple of days al

y its forced immobility and by the Scolia's bites. The victim is in possession of its full power of sensation; and it expresses the pain experienced as best it may, by contractions. Embarrassed by these tremors, these twitches of suffering flesh, incommoded at every mouthful, the grub chews away at random and kills the larva almost as soon as it

nt to the nature of the game, though the mother always supplies them with the same diet. I had succeeded in rearing them on a great variety of prey, without paying regard to their normal fare. I shall return

ts belly and I place the Scolia on the opening. The dish pleases my charge; and it would be strange indeed if this were not so, considering that another Scolia-grub, the larva of the Garden Scolia, feeds on the Oryctes. The dish suits it, for before long it has burrowed half-way into the succulent paunch. This time all goes well. Will the rearing be successful? Not a bit of it!

strip of cork. As usual, I make a small opening in the belly, to entice the grub by means of a bleeding wound and facilitate its access. I obtain the same negative result. In a little while, the Oryctes is a

o perfection: yesterday, in a warm sheltered corner, at the foot of a sandy bank, I discovered three cells of the Languedocian Sphex, each with its Ephippiger and the recently laid egg

l to them, without any sign of repugnance or hesitation. By the fluctuations of the digestive canal I perceive that the work of nutrition is proceeding as it should; things are happening just as if the dish were a Cetonia-larva. The change of diet, complete though

eal for nearly a fortnight, grows thin and empty, shrivels up and yet retains to the very end the freshness peculiar to living flesh. Substitute for this Sphex-larva a Scolia-larva of almost the same size; let the dish be the same though the guest is d

erties. The three Ephippigers were operated on by the Sphex. Able to keep fresh under the mandibles of the Sphex-larvae, why did they promptly go bad under the mandibles of the Scolia-larvae? Any id

you can discover the reason why the victuals keep fresh when consumed by a Sphex, whereas they promptly become putrid

t, if it has to browse upon a Cetonia-grub, whose different structure would confuse its talents as a dissector, it would soon have nothing before it but a heap of putrescence. The Scolia, in its turn, is familiar with the method of eating the Cetonia-grub, its invariable portion; but it does n

game goes high; and they die when putridity supervenes. Their death, therefore, is due not to an unaccustomed diet, but to poisoning by one or other of those terrible toxins which are engendered by animal corruption and which chemistry calls by the name of ptomaines.

ess condition of not killing it until the very end! Could our physiological science, of which, with good reason, we are so proud, describe, without blundering, the method to be f

food without causing putrescence had been practised, with all its scrupulous caution, from the first generation onwards. Having as yet learnt nothing by habit or by atavistic transmission, since it was making a first beginning, the nurseling would bite into its provender at random. It would

ey are the descendants of carvers that have practised their art since Scoliae first came into the world; nevertheless they all perish from the decomposition of the rations supplied, when I try to feed them on Ephippigers paralysed by the Sphex. Very expert in the method of attacking the Cetonia, they do not know how to set about the business of discreetly consuming a species of game new to them. All that escapes them is a few details, for the trade of an o

e can have led at the first trial to success in a system of nourishment so full of pit-falls: fortuitous results are preposterous amid so many complications. Either the feeding is strictly methodical at the beginning, in conformity with t

the little ball, as small as you please. Now, in harking back to the origin of these acquired habits, if I interrogate the possibilities I obtain zero as the only answer. If the animal does not know its trade thoroughly, if it has to acquire something, all the more if it has to acquire everything, it perishes: that is inevita

ous premises likes me no better. I observe, I experiment and I let the facts speak for themselves. We have just