New-comers into the country which the trap-door spider inhabits, are often as surprised as Ali Baba in the ‘Forty Thieves’ by seeing the ground open, a little lid lifted up, and a grim black-haired spider peer about as if to reconnoitre the position before sallying out of its fortress. At the least movement on the part of the spectator, down drops the spider disappearing into its hole, the door closes and the astonished observer, unable to find its traces in the apparently unbroken soil doubts whether his eyes have not deceived him. Nothing short of actual violence will induce the trap-door spider to vacate the premises it has so admirably constructed. It holds on with all its might and will permit the earth to be excavated around its burrow and the whole nest to be removed without deserting its home. But all its energy vanishes as soon as it is removed from the burrow it so pertinaciously defended; it then loses all its activity, remains fixed to the spot as if stupified, or at the best walks languidly about like one who has lost all that made existence valuable.
At Caldera, Mr. Adams observed a dingy little species of spider of the genus Clubiona, concealing itself in very snug retreats formed out of a dead leaf, rolled round in the shape of a cylinder, lined with a soft silken tissue, and closed at one end by means of a strong woven bolt-door. When hunted, it was amusing to see the frightened little creatures run for protection into their tiny castles, where they would doubtless be safe from the attacks of birds, owing to the leaves not being distinguishable from others that strew the ground.
All species of spiders are gifted with an admirable maternal instinct, and resort to various methods for the purpose of securing their cocoons. The Theridion, when a seizure of the precious burden is threatened, tumbles together with it to the ground, and remains motionless, while the Thorinsa covers it with its body, and when robbed of it, wanders about disconsolate. In a forest of the Sooloo Islands, Mr. Adams found the ground literally overrun with a small black agile species of Lycosa, many of which had a white flattened globose cocoon affixed to the end of their abdomen. It was most amusing to watch the care with which these jealous mothers protected the cradles of their little ones, allowing themselves to fall into the hands of the enemy rather than be robbed of the silken nests that contained them.
If the spiders are at war with all other insects, and contribute to keep them within bounds by the destruction they cause among their ranks, they in their turn are sorely persecuted creatures. Monkeys, squirrels, lizards, tortoises, frogs, and toads catch and devour them wherever they can. In Java and Sumatra, we even find a family of sparrows named Arachnotheræ, from their living almost exclusively on spiders. Armed with a prodigiously long recurved and slender beak, these birds know how to pursue them and drag them forth from the most obscure recesses.
It is amongst the insects, however, that the spiders have to fear their most numerous and formidable enemies. Independently of those which they find in their own class, the centipedes seize them beyond the possibility of escape; and several species of wasps, more savage and poisonous than themselves, will rush upon spiders eight times their size and weight, and benumbing them with a sting, bear them off to their nests, to serve as food for their larvæ.
Others attack the spiders in their progeny. The Pimpla Arachnitor pierces with its invisible gimlet the tender skin of the spider’s egg, and, without tearing it, introduces its own eggs into the liquid. The pimpla’s egg soon comes to maturity, and the larva devours the substance of that of the spider, from whence a winged insect bursts forth—a phenomenon which made some naturalists, too hasty to judge from appearances, believe that spiders were able to procreate four winged flies.
Notwithstanding the disgust or horror which they generally inspire, the spiders are, with very rare exceptions, by no means injurious to man. However promptly their venom may act upon insects, even that of the largest species of Northern Europe produces, on coming into contact with our skin, no pain or inflammation equalling in virulence that of the wasp, the bee, the gnat, or other insects of a still smaller size. The giant spiders of a sunnier sky, armed with more formidable weapons, naturally produce a more painful sting; but even here the effects have been much exaggerated.
In the country of the Makalolo, Dr. Livingstone, feeling something running across his forehead as he was falling asleep, put up his hand to wipe it off, and was sharply stung, both on the hand and head; the pain was very acute. On obtaining a light, he found that it had been inflicted by a light-coloured spider about half an inch in length; but one of the negroes having crushed it with his fingers, he had no opportunity of examining whether the pain had been produced by poison from a sting, or from its mandibles. No remedy was applied, and the pain ceased in about two hours.
If thus, among the many species of spiders, hardly a single one may be said to be formidable to man, the indirect services which they render him—by diminishing the number of noxious insects—are far from inconsiderable.
In several countries where insects cause great ravages, the services of the spiders are duly appreciated. Thus in the West Indies, a large and formidable trap-door spider, which would make a European start back with horror, is looked upon with pleasure by the islanders of the torrid zone, who respect it as a sacred animal, by no means to be disturbed or harmed, as it delivers them from the cockroaches, which otherwise would overrun their dwellings. Those who do not possess these spiders take good care to purchase and transport them into their houses, expecting from them similar services to those we derive from a good domestic cat. The spectacle of a trap-door spider bounding on a cockroach, with all the ferocity of a tiger springing on its prey, would no doubt have all the interest of a bull-fight if the diminutive size of the combatants were swelled to more ample proportions. Mr. E. Layard has described one of these encounters which he witnessed near a ruined temple in Ceylon. When about a yard apart, each of the enemies discerned the other and stood still, the spider with his legs slightly bent and his body raised, the cockroach confronting him, and directing his antennæ with a restless undulation towards his enemy. The spider, by stealthy movements, approached to within a few inches, and paused, both parties eyeing each other intently; then suddenly a rush, a scuffle, and both fell to the ground, when the blatta’s wings closed; the spider seized it under the throat with his claws, and when he had dragged it into a corner, the action of his jaws was distinctly audible. Next morning, Mr. Layard found the soft parts of the body had been eaten, nothing but the head, thorax, and elytra remaining.