Puslapio vaizdai
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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

warmer season.

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

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.

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

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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.

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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

her method of attack, why has not the Segestria perfected her method of defense? Is it possible that century upon century should have modified the one to its advantage without succeeding in modifying the other? Here I am utterly at a loss, and I say to myself, in all simplicity, since the Pompili must have spiders, the former have possessed their patient cunning and the other their foolish audacity from all time. This may be puerile, if you like to think it so, and not in keeping with the transcendental aims of our fashionable theorists. The argument contains neither the subjective nor the objective point of view; neither adaptation nor differentiation; neither atavism nor evolution. Very well; but at least I understand it.

Let us return to the habits of Pompilus apicalis. Without expecting results of any particular interest, for in captivity the respective talents of the huntress and the quarry seem to slumber, I place together, in a wide jar, a wasp and a Segestria. The spider and her enemy mutually avoid each other, both being equally timid. A judicious shake or two brings them into contact. The Segestria, from time to time, catches hold of the Pompilus, who gathers herself up as best she can, without attempting to use her sting; the spider rolls the insect between her legs and even between her mandibles, but appears to dislike doing it. Once I see her lie on her back and hold the Pompilus above her, as far away as possible, while turning her over in her fore legs and munching at her with her mandibles. The wasp, whether by her own adroitness or owing to the spider's dread of her, promptly escapes from the terrible fangs; moves to a short distance, and does not seem to trouble unduly about the buffeting which she has received. She quietly polishes her wings and curls her antennæ by pulling them while standing on them with her fore tarsi. The attack of the Segestria, stimulated by my shakes, is repeated ten times over; and the Pompilus always escapes from the venomous fangs unscathed, as though she were invulnerable.

Is she really invulnerable? By no means, as we shall soon have proved to

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us; if she retires safe and sound, it is because the spider does not use her fangs. What we see is a sort of truce, a tacit convention forbidding deadly strokes, or rather the demoralization due to captivity; and the two adversaries are no longer in a sufficiently warlike mood to make play with their daggers. The tranquillity of the Pompilus, who keeps on jauntily curling her antennæ in the face of the Segestria, reassures me as to my prisoner's fate; for greater security, however, I throw her a scrap of paper, in the folds of which she will find a refuge during the night. She installs herself there, out of the spider's reach. Next morning I find her dead. During the night the Segestria, whose habits are nocturnal, has recovered her daring and stabbed her enemy. I had my suspicions that the parts played might be reversed! The butcher of yesterday is the victim of to-day.

I replace the Pompilus by a hive-bee. The interview is not protracted. Two hours later the bee is dead, bitten by the spider. A drone-fly suffers the same fate. The Segestria, however, does not touch either of the two corpses any more than she touched the corpse of the Pompilus. In these murders the captive seems to have no other object than to rid herself of a turbulent neighbor. When appetite awakes, perhaps the victims will be turned to account. They were not, and the fault was mine. I placed in the jar a bumblebee of average size. A day later the spider was dead; the rude sharer of her captivity had done the deed.

Let us say no more of these unequal duels in the glass prison and complete the story of the Pompilus, whom we left with the paralyzed Segestria at the foot of the wall. She abandons her prey on the ground and returns to the wall. She visits the spiders' funnels one by one, walking on them as freely as on the stones; she inspects the silken tubes, plunging her antennæ into them, sounding and exploring them; she enters without the least hesitation. Whence does she now derive the temerity thus to enter the spiders' lairs? Only a little while ago she was displaying extreme caution; at this moment she seems

heedless of danger. The fact is that there is really no danger. The wasp is inspecting uninhabited houses. When she dives down a silken tunnel, she very well knows that there is no one in; for, had the Segestria been there, she would by this time have appeared on the threshold. The fact that the householder does not show herself at the first vibration of the neighboring threads is a certain proof that the tube is vacant; and the Pompilus enters in full security. I shall recommend future observers not to take the present investigations for hunting tactics. I have already remarked, and I repeat, the Pompilus never enters the silken ambush while the spider is there.

Among the funnels inspected, one appears to suit her better than the others; she returns to it frequently in the course of her investigations, which last for nearly an hour. From time to time she hastens back to the spider lying on the ground. She examines her, tugs at her, drags her a little closer to the wall, then leaves her the better to reconnoiter the tunnel which is the object of her preference. Lastly, she returns to the Segestria and takes her by the tip of the abdomen. The quarry is so heavy that she has great difficulty in moving it along the level ground. Two inches divide it from the wall. She gets to the wall, but not without effort; nevertheless, once the wall is reached, the job is quickly done. We learn that Antæus, the son of Mother Earth, in his struggle with Hercules, received new strength as often as his feet touched the ground; the Pompilus, daughter of the wall, seems to increase her powers tenfold once she has set foot on the masonry.

For here the wasp hoists her prey backward, her enormous prey, which dangles beneath her. She climbs now up a vertical plane, now a slope, according to the uneven surface of the stones. She crosses gaps where she has to go belly uppermost, while the quarry swings to and fro in the air. Nothing stops her; she keeps on climbing, to a height of six feet or more, without selecting her path, without seeing her goal, since she goes backward. Here is a lodge, no doubt reconnoitered beforehand and now reached, despite

the difficulties of an ascent which did not allow her to see it. The Pompilus lays her prey on it. The silken tube which she inspected so lovingly is only some eight inches distant. She goes to it, examines it rapidly, and returns to the spider, whom she at length lowers down the tube.

Shortly afterward I see her come out again. She searches here and there on the wall for a few scraps of mortar, two or three fairly large pieces, which she carries to the tube, to close it up. The task is done. She flies away.

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Next day I inspect this strange burrow. The spider is at the bottom of the silken tube, isolated on every side, as though in a hammock. The wasp's egg is glued not to the ventral surface of the victim, but to the back, about the middle, near the beginning of the abdomen. It is white, cylindrical, and about a twelfth of an inch long. few scraps of mortar which I saw carried have but very roughly cut off the silken chamber at the end. Thus Pompilus apicalis lays her quarry and her eggs not in a burrow of her own making, but in the spider's actual house. Perhaps the silken tube belongs to this very victim, which in that event provides both board and lodging. What a shelter for the larva of this Pompilus, the warm retreat and downy hammock of the Segestria!

Here, then, already, we have two spider-huntresses, the Winged Pompilus and Pompilus apicalis, who, unversed in the miner's craft, establish their offspring inexpensively in accidental chinks in the walls, or even in the lair of the spider on which the larva feeds. In these cells, acquired without exertion, they build only an attempt at a wall with a few fragments of mortar. But we must beware of generalizing about this expeditious method of establishment. Other Pompili are true diggers, who valiantly sink a burrow in the soil to a depth of a couple of inches. These include the Eight-spotted Pompilus (Pompilus octopunctatus, Panz.), with her black-and-yellow livery and her amber wings, a little darker at the tips. For her game she chooses the Epeira (E. fasciata, E. serica), those garden spiders, magnificently adorned, who lie in wait at the center of their webs.

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