« AnkstesnisTęsti »
like a bloater. She is rare; I see three or four of her in the course of the year, and I never fail to halt in the presence of the proud creature, rapidly striding through the dust of the fields when the dog-days arrive. Its audacious air, its uncouth gait, its warlike bearing, long made me suspect that to obtain its prey it had to make some impossible, terrible, unspeakable capture; and my guess was correct. By dint of waiting and watching I beheld that victim; I saw it in the huntress's mandibles. It is the Black-bellied Tarantula, the terrible spider who slays a carpenter-bee or a bumblebee outright with one stroke of her weapon, the spider who kills a sparrow or a mole, the formidable creature whose bite would perhaps not be without danger to ourselves. Yes, this is the bill of fare which the proud Pompilus provides for her larva.
This spectacle, one of the most striking with which the hunting wasps have ever provided me, has as yet been offered to my eyes but once, and that was in the paddock adjoining my rural home. I can still see the intrepid poacher dragging by the leg, at the foot of a wall, the monstrous prize which she had just secured, doubtless at no great distance. At the base of the wall was a hole, an accidental chink between some of the stones. The wasp inspected the cavern, not for the first time; she had already reconnoitered it, and the premises had satisfied her. The prey, deprived of the power of movement, was waiting somewhere, I know not where; and the huntress had gone back to fetch it and store it away. It was at this moment that I met her. The Pompilus gave a last glance at the cave, removed a few small fragments of loose mortar, and with that her preparations were completed. The Lycosa1 was introduced, dragged along, belly upward, by one leg. I did not interfere. Presently, the wasp reappeared on the surface and carelessly pushed in front of the hole the bits of mortar which she had just extracted from it; then she flew away. It was all over, the egg was laid, the insect had finished for better or for worse, and I was able to proceed with my examination of the burrow and its contents.
1The spider in question is known indifferently as the Black-bellied Tarantula and the Narbonne Lycosa.
The Pompilus has done no digging. It is really an accidental hole, with spacious, winding passages, the result of the mason's negligence and not of the wasp's industry. The closing of the cavity is quite as rough and ready. A few crumbs of mortar heaped up before the doorway form a barricade rather than a door. A mighty hunter makes a poor architect. The tarantula's murderess does not know how to dig a cell for her larva, she does not know how to fill up the entrance by sweeping dust into it. The first hole encountered at the foot of a wall contents her, provided that it be roomy enough; a little heap of rubbish will do for a door. Nothing could be more expeditious.
I withdraw the game from the hole. The egg is stuck to the spider, near the beginning of the belly. A clumsy movement on my part makes it fall off at the moment of extraction. It is all over: the thing will not hatch; I shall not be able to observe the development of the larva. The tarantula lies motionless, as flexible as in life, with not a trace of a wound. In short, we have here life without movement. From time to time the tips of the tarsi quiver a little, and that is all. Accustomed of old to these deceptive corpses, I can see in my mind's eye what has happened: the spider has been stung in the region of the thorax, no doubt once only, in view of the concentration of her nervous system. I place the victim in a box, in which it retains all the pliancy and all the freshness of life from the second of August to the twentieth of September; that is to say, seven weeks. These miracles are familiar to us; there is no need to linger over them here.
The most important matter has escaped me. What I wanted, what I still want, to see, is the Pompilus engaged in mortal combat with the Lycosa. What a duel, in which the cunning of the one has to overcome the terrible weapons of the other! Does the wasp enter the burrow to surprise the tarantula at the bottom of her lair? Such temerity would be fatal to her. Where the big bumblebee dies an instant death, the audacious visitor would perish the moment she entered. Is not the other
there, facing her, ready to snap at the back of her head, inflicting a wound which would result in sudden death? No, the Pompilus does not enter the spider's parlor, that is obvious. Does she surprise the spider outside her fortress? But the Lycosa is a stay-athome animal; I do not see her straying abroad during the summer. Later, in the autumn, when the Pompili have disappeared, she wanders about; turning Gipsy, she takes the open air with her numerous family, which she carries on her back. Apart from these maternal strolls, she does not appear to me to leave her castle; and the Pompilus, I should think, has no great chance of meeting her outside. The problem, we perceive, is becoming complicated: the huntress cannot make her way into the burrow, where she would risk sudden death; and the spider's sedentary habits make an encounter outside the burrow improbable. Here is a riddle which would be interesting to decipher. Let us endeavor to do so by observing other spider-hunters; analogy will enable us to draw a conclusion.
I have often watched Pompili of every species on their hunting expeditions, but I have never surprised them entering the spider's lodging when the latter is at home. Whether this lodging be a funnel plunging its neck into a hole in some wall, an awning stretched amid the stubble, a tent modeled upon the Arab's, a sheath formed of a few leaves bound together, or a net with a guardroom attached, whenever the owner is indoors, the suspicious Pompilus holds aloof. When the dwelling is vacant, it is another matter; the wasp moves with arrogant ease over those webs, springs, and cables, in which so many other insects would remain ensnared. The silken threads do not seem to have any hold upon her. What is she doing, exploring those empty webs? She is watching to see what is happening on the adjacent webs where the spider is ambushed. The Pompilus therefore feels an insuperable reluctance to make straight for the spider when the latter is at home in the midst of her snares. And she is right a hundred times over. If the tarantula understands the practice of the dagger-thrust in the neck,
which is immediately fatal, the other cannot be unacquainted with it. Woe, then, to the imprudent wasp who presents herself upon the threshold of a spider of approximately equal strength!
Of the various instances which I have collected of this cautious reserve on the spider huntress's part, I shall confine myself to the following, which will be sufficient to prove my point. By joining three leaflets together with silken strands, a spider has built herself a green arbor, a horizontal sheath, open at each end. A questing Pompilus comes upon the scene, finds the game to her liking, and pops in her head at the entrance of the cell. The spider immediately retreats to the other end. The huntress goes round the spider's dwelling and reappears at the other door. Again the spider retreats, returning to the first entrance. The wasp also returns to it, but always by the outside. Scarcely has she done so, when the spider rushes for the opposite opening; and so on for fully a quarter of an hour, both of them coming and going from one end of the cylinder to the other, the spider inside and the Pompilus outside.
The quarry was a valuable one, it seems, since the wasp persisted for a long time in her attempts, which were invariably defeated; the huntress had to abandon them, however, baffled by this perpetual running to and fro. The Pompilus made off, and the spider, once more on the watch, patiently awaited the heedless midges. What should the wasp have done to capture this muchcoveted game? She should have entered the verdant cylinder, the spider's dwelling, and pursued the spider direct, in her own house, instead of remaining outside, going from one door to the other. With such swiftness and dexterity as hers, it seemed to me impossible that the stroke should fail; for the quarry moved clumsily, a little sidewise, like a crab. I judged it to be an easy matter; the Pompilus thought it highly dangerous. To-day I am of her opinion. If she had entered the leafy tube, the mistress of the house would have operated upon her neck, and the huntress would have become the quarry.
Years passed, and the paralyzer of
the spiders still refused to reveal her secret; I was badly served by circumstances, could find no leisure, was absorbed in unrelenting preoccupations. At length, during my last year at Orange, the light dawned upon me. My garden was inclosed by an old wall, blackened and ruined by time, where, in the chinks between the stones, lived a population of spiders, represented more particularly by Segestria perfidia. This is the common black spider, or cellar spider. She is deep black all over, excepting the mandibles, which are a splendid metallic green. Her two poisoned daggers look like a product of the metal-worker's art, like the finest bronze. In any mass of abandoned masonry there is not a quiet corner, not a hole the size of one's finger, in which the Segestria does not set up house. Her web is a widely flaring funnel, whose open end, at most a span across, lies spread upon the surface of the wall, where it is held in place by radiating threads. This conical surface is continued by a tube which runs into a hole in the wall. At the end is the diningroom, to which the spider retires to devour at ease her captured prey.
With her two hind legs stuck into the tube to obtain a purchase and the six others spread around the orifice, the better to perceive on every side the quiver which gives the signal of a capture, the Segestria waits motionless, at the entrance of her funnel, for an insect to become entangled in the snare. Large flies, drone-flies, dizzily grazing some thread of the snare with their wings, are her usual victims. At the first flutter of the netted fly, the spider runs or even leaps forward, but she is now secured by a cord which escapes from the spinnerets and which has its end fastened to the silken tube. This prevents her from falling as she darts along a vertical surface. Bitten at the back of the head, the drone-fly is dead in a moment, and the Segestria carries him into her lair.
Thanks to this method and these hunting appliances, an ambush at the bottom of a silken whirlpool, radiating snares, a life-line which holds her from behind and allows her to take a sudden rush without risking a fall,—the Seges
tria is able to catch game less inoffensive than the drone-fly. A common wasp, they tell me, does not daunt her. Though I have not tested this, I readily believe it, for I well know the spider's boldness.
This boldness is reinforced by the activity of the venom. It is enough to have seen the Segestria capture some large fly to be convinced of the overwhelming effect of her fangs upon the insects bitten in the neck. The death of the drone-fly, entangled in the silken funnel, is reproduced by the sudden death of the bumblebee on entering the tarantula's burrow. We know the effect of the poison on man, thanks to Antoine Duges's investigations. Let us listen to the brave experimenter:
The treacherous Segestria, or great cellar spider, reputed poisonous in our part of the country, was chosen for the principal subject of our experiments. She was three quarters of an inch long, measured from the mandibles to the spinnerets. Taking her in my fingers from behind, by the legs, which were folded and gathered together (this is the way to catch hold of live spiders, if you would avoid their bite and master them without mutilating them), I placed her on various objects and on my clothes without her manifesting the least desire to do any harm; but hardly was she laid on the bare skin of my forearm when she seized a fold of the epidermis in her powerful mandibles, which are of a metallic green, and drove her fangs deep into it. For a few moments she remained hanging, although left free; then she released herself, fell, and fled, leaving two tiny wounds a sixth of an inch apart, red, but hardly bleeding, with a slight extravasation round the edge and resembling the wounds produced by a large pin.
At the moment of the bite the sensation was sharp enough to deserve the name of pain, and this continued for five or six minutes more, but not so forcibly. I might compare it with the sensation produced by the stinging-nettle. A whitish tumefaction almost immediately surrounded the two pricks, and the circumference, within a radius of about an inch, was colored an erysipelas red, accompanied by a very slight swelling. In an hour and a half it had all disappeared, except the mark of the pricks,
which persisted for several days, as any other small wound would have done. This was in September and in rather cool weather. Perhaps the symptoms would have displayed somewhat greater severity at a
wasp passes near an inhabited funnel. The spider, on the lookout, at once shows herself on the threshold of her dwelling, half out of her tube, ready for defense and perhaps also for attack. The Pompilus moves away, and the Segestria reënters her tube. A fresh alarm: the Pompilus returns; another threatening demonstration on the part of the spider. Her neighbor, a little later, does better than this: while the huntress is prowling about in the neighborhood of the funnel, she suddenly leaps out of the tube, with the life-line, which will save her from falling should she miss her footing, attached to her spinnerets; she rushes forward, and hurls herself in front of the Pompilus, at a distance of some eight inches from her burrow. The wasp, as though terrified, immediately decamps, and the Segestria no less suddenly retreats indoors.
Without being serious, the effect of the Segestria's poison is plainly marked. A sting causing sharp pain and swelling, with the redness of erysipelas, is no trifling matter. While Duges's experiment reassures us in so far as we ourselves are concerned, it is none the less the fact that the cellar spider's poison is a terrible thing for the insects, whether because of the small size of the victim, or because it acts with special efficacy upon an organization which differs widely from our own. One Pompilus, though greatly inferior to the Segestria in size and strength, nevertheless makes war upon the black spider and succeeds in overpowering this formidable quarry. This is Pompilus apicalis, Van Der Lind, who is hardly larger than the hive-bee, but very much slenderer. She is of a uniform black; her wings are a cloudy brown, with transparent tips. Let us follow her in her expeditions to the old wall inhabited by the Segestria; we will track her for whole afternoons during the July heats; and we will arm ourselves with patience, for the perilous capture of the game must take the wasp a long time.
The spider huntress explores the wall minutely; she runs, leaps, and flies; she comes and goes, flitting to and fro. The antennæ quiver; the wings, raised above the back, continually beat one against the other. Ah, here she is, close to a Segestria's funnel! The spider, who has hitherto remained invisible, instantly appears at the entrance to the tube; she spreads her six fore legs outside, ready to receive the huntress. Far from fleeing before the terrible apparition, she watches the watcher, fully prepared to prey upon her enemy. Before this intrepid demeanor the Pompilus draws back. She examines the coveted game, walks round it for a moment, then goes away without attempting anything. When she has gone, the Segestria retires indoors, backward. For the second time the
Here, we must admit, is a strange quarry: it does not hide, but is eager to show itself; it does not run away, but flings itself in front of the hunter. If our observations were to cease here, could we say which of the two is the hunter and which the hunted? Should we not feel sorry for the imprudent Pompilus? Let a thread of the trap entangle her leg, and it is all up with her. The other will be there, stabbing her in the throat. What, then, is the method which she employs against the Segestria, always on the alert, ready for defense, audacious to the point of aggression? Shall I surprise the reader if I tell him that this problem filled me with the most eager interest, that it held me for weeks in contemplation before that cheerless wall? Nevertheless, my tale will be a short one.
On several occasions I see the Pompilus suddenly fling herself on one of the spider's legs, seize it with her mandibles, and endeavor to draw the animal from its tube. It is a sudden rush, a surprise attack, too quick to permit the spider to parry it. Fortunately, the latter's two hind legs are firmly hooked to the dwelling, and the Segestria escapes with a jerk; for the other, having delivered her shock attack, hastens to release her hold. If she persisted, the affair might end badly for her. Having failed in this assault, the wasp repeats the procedure
at other funnels; she will even return to the first when the alarm is somewhat assuaged. Still hopping and fluttering, she prowls around the mouth, whence the Segestria with her legs outspread, watches her. She waits for the propitious moment; she leaps forward, seizes a leg, tugs at it, and springs out of reach. More often than not the spider holds fast; sometimes she is dragged out of the tube to a distance of a few inches, but immediately returns, no doubt with the aid of her unbroken life-line.
The Pompilus's intention is plain: she wants to eject the spider from her fortress and fling her some distance away. So much perseverance leads to success. This time all goes well. With a vigorous and well-timed tug the wasp has pulled the Segestria out, and at once lets her drop to the ground. Bewildered by her fall, and even more demoralized by being wrested from her ambush, the spider is no longer the bold adversary that she was. She draws her legs together and cowers into a depression in the soil. The huntress is there on the instant to operate upon the evicted spider. I have barely time to draw near to watch the tragedy, when the victim is paralyzed by a thrust of the sting in the thorax.
Here at last, in all its Machiavellian cunning, is the shrewd method of the Pompilus. She would be risking her life if she attacked the Segestria in her home. The wasp is so convinced of this that she takes good care not to commit this imprudence; but she knows also that, once dislodged from her dwelling, the spider is as timid, as cowardly as she was audacious at the center of her funnel. The whole point of her tactics, therefore, lies in dislodging the creature. This done, the rest is nothing.
The tarantula-huntress must behave in the same manner. Enlightened by her kinswoman, Pompilus apicalis, my mind pictures her wandering stealthily around the Lycosa's rampart. The Lycosa hurries up from the bottom of her burrow, believing that a victim is approaching; she ascends her vertical tube, spreading her fore legs outside, ready to leap. But it is the Pompilus who leaps, seizes a leg, tugs it, and hurls the Lycosa outside her burrow.
She is henceforth a craven victim, who will let herself be stabbed without dreaming of employing her venomous fangs. Here craft triumphs over strength; and this craft is not inferior to mine, when, wishing to capture the tarantula, I make, her bite a spike of grass that I dip into the burrow, lead her gently to the surface, and then with a sudden jerk throw her outside. For the entomologist, as for the Pompilus, the essential thing is to make the spider leave her stronghold. After this there is no difficulty in catching her, thanks to the utter bewilderment of the evicted creature.
Two contrasting points impress me in the facts which I have just set forth the shrewdness of the Pompilus and the folly of the spider. I will admit that the wasp may gradually have acquired, as being highly beneficial to her posterity, the instinct by which she first of all judiciously drags her victim from its refuge in order there to paralyze it without incurring danger, provided that you will explain why the Segestria, possessing an intellect no less gifted than that of the Pompilus, does not yet know how to counteract the trick of which she has long been the victim. What would the black spider need to do to escape her exterminator? Virtually nothing. It would be enough for her to reënter her tube, instead of coming up to post herself at the entrance like a sentry, whenever the enemy is in the neighborhood. It is very brave of her, I agree, but it is also very risky. The Pompilus will pounce upon one of the legs spread outside the burrow for defense and attack, and the besieged spider will perish, betrayed by her own boldness. This posture is excellent when waiting for prey, but the wasp is not a quarry. She is an enemy, and one of the most dread of enemies. The spider knows this. At the sight of the wasp, instead of posting herself fearlessly, but foolishly, on her threshold, why does she not retreat into her fortress, where the other would not attack her? The accumulated experience of generations should have taught her this elementary tactical device, which is of the greatest value to the prosperity of her race. If the Pompilus has perfected