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forming the anterior portion, which is small in comparison. To this section the legs are attached, these being eight in number -two more than insects are furnished with. Spiders are destitute of antennæ-those feelers which proceed from the heads of insects—but are provided with a pair of saw-like pincers, which terminate in sharp points. These points are perforated by a small hole, through which the animal emits a poison, which is eminently fatal to most of the smaller insects. These pincers lie folded one upon the other, and are never extended unless in defence, or in the capture of prey. The eyes are simple, and not compound, like those of insects; and are generally six or eight in number, dispersed over the head so as to command a wide range of vision. The arrangement of the eyes varies much in the different families and genera which are distinguished by naturalists. Spiders are all strictly air-breathing animals, and their apparatus for this purpose differs from that of insects. Their skin, or crust, is more leathery than horny; and this they cast periodically during their lifetime. Like crabs and some other animals, they have the power of reproducing lost limbs-a casualty to which their predatory habits render them frequently liable.
One of the most remarkable features in the structure and economy of spiders is the power which many of them possess of emitting slender threads of a silk-like substance, of which they construct nets, or long dangling cables; and on these some of them, as the
gossamer-spiders, are buoyed through A s the air with nearly as much facility as
though they had been furnished with wings. The apparatus provided by nature for elaborating and emitting the spider's web is a beautiful piece of mechanism. Within the animal there are several little bags or vesicles containing a gummy matter; and these vesicles are connected with a circular orifice situated at the abdomen. Within this orifice are five little teats, or spinnerets, through which the thread is drawn, as represented in the accompanying figure ; and on its exposure to the air, the soft gummy substance immediately hardens into a
thread. It must not be concluded, however, that there is only a simple thread produced by each spinneret; the fact is, these teats are studded with thousands of minute tubes, too small for the naked eye to perceive, and each of these emits á thread of inconceivable fineness. These minute tubes are known as spinnerules, and the films which proceed from them unite like so many strands of a rope, to form the thread by which a
spider suspends itself, or of which it forms its net. The finest thread which human mechanism can produce, is like a ship's cable compared with the delicate films which flow from the spinnerules of the largest spider. These films are all distinctly separate on coming from the spinneret ; but unite, as shewn in the adjoining cut, at a short distance, not by any twisting process, but merely by their own glutinous or gummy nature. Thus, the spinning apparatus of the disdained spider, when viewed by the eye of science, becomes one of the most wonderful pieces of animated mechanism, and is of itself sufficient to establish that nothing short of Divinity could have framed it. The animal has great command over this apparatus, and can apply it at will so long as the receptacles within are replenished with the gummy fluid; but as soon as this gum is exhausted, all its efforts to spin are fruitless, and it must wait till nature, by her inscrutable chemistry, has secreted it from the food which is devoured.
With regard to the sexes, male spiders are always much smaller than the females of the same species, being sometimes not more than one-fourth the size. The female lays a considerable number of round whitish eggs, which, by some species, are merely dropped into a crevice, without any protection ; by others they are enclosed in a globular cover of web; and by many they are deposited in an irregular mass, and then worked over with a soft envelope. The attention which they pay to these cocoons almost equals that of the ant for its larvæ. A spider may be often seen dragging a ball of eggs much larger than its own body; and though scared, will return again and again to secure its charge. We once deprived a gardenspider of its eggs, and covered them slightly with earth; the animal scampered away for a few feet, and then gathered up its legs, and lay down as if dead. In a short time, when all was quiet, it returned to the spot, and searched round every clod and pellet till it ultimately discovered the object of its search, which it gently uncovered, cleaned, enveloped with a few rounds of fresh web, and then bore rapidly away to a secret crevice. So powerful, indeed, is the spider's affection for her young, that, according to Professor Hentz, 'all her limbs, one by one, may be torn from her body without forcing her to abandon her hold. But if, without mangling the mother, the cocoon be skilfully removed from her, and suddenly thrown out of sight, she instantaneously loses all her activity, seems paralysed, and coils her tremulous limbs as if mortally wounded. If the bag be returned, her ferocity and strength are restored the moment she has any perception As to national therefore cannot taking place be being able to ta it in exactly the inhabitants of a
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Such are the prominent characteristics of spiders as to their structure and organisation. We shall now consider the habits and economy of some of the more remarkable species-illustrating, when possible, by appropriate anecdote.
THE HOUSE-SPIDER. The house-spider (Aranea domestica), though not the most abundant, is perhaps the best known of our native species-being very common in neglected houses, where it spreads its web unmolested for the capture of flies, moths, and other insects. The site of its operations is generally chosen for the double purpose of plunder and security—a fact which will account for its web being often found in retired and shady nooks, the most unlikely places for a fly to enter. The shape of the web is in a great measure determined by the nature of the spot in which it is spread; for the most part we see it of a triangular form in corners, with the den or funnel placed at the farthest angle, in which the creature lies on watch for its prey. In commencing this structure, the spider passes from side to side till it has fixed several strong threads, or chains, which serve as the basis of the web. These it doubles and redoubles, and tightens by stays, which are often carried out to some distance ; indeed, no suspensionbridge was ever constructed on more correct principles of strain and tension. The framework being hung, the creature next proceeds to lay the warp and woof-we say lay, for these are not interlaced like the warp and woof of the human artist, but simply cross each other, their glutinous nature giving them sufficient adhesion. Great ingenuity is often displayed in rendering this web equally strong on all sides. Thus the strands of the outer extremity are always thicker than those upon which there is less strain ; and if the wind agitates it more on one side than another, that side is sure to have additional stays thrown out to keep it steady. When the web is accidentally injured or torn during the capture of some large fly, the spider soon renews it; but there is no foundation for the story that she sweeps the dust from it by shaking it with her paws. The truth is, that when it becomes much defiled with dust, it is deserted for a new habitation.
It has been stated that the house-spider forms a funnel, or cell, at the interior angle of this web, in which it lies in wait, and into which it drags its prey, to devour it at leisure. To this cell all the rays of the web converge; so that if a line at the farthest extremity be touched, the vibration is instantaneously conveyed to the centre. A poor fly, therefore, no sooner impinges upon the net, than out the spider springs to reconnoitre the cause of the disturbance. If it be a fly or moth of ordinary dimensions, the spider bounds boldly forward, grasps it in its claws, and sends its poisoned fangs into
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