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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 its body; and so fatal is this operation, that a few seconds terminate

last.' The young of some species are fed for a short while by the parent; but the majority, we believe, shift for themselves on leaving the envelope, and soon arrive at maturity.

Thrown early on their own resources, the young spiders commence a solitary life, lurking in holes and corners for the prey which may fall within their reach. Everywhere are they seen fabricating their snares-in the fields, on trees and shrubs, on the grass, and in the earth; and if we watch their proceedings, we may sometimes see them ascend into the air, where, borne by their webs as by an airballoon, they can elevate themselves to a great height. In this manner they often appear in vast numbers, and at a great distance from land. In 1811, the river Tagus was covered for more than half an hour with their floating webs; and in October 1826, Mr Blackwall found every field and hedge in his neighbourhood covered with a confused network of shining lines, thickly coating his feet and ankles as he walked across a pasture. In the autumn of 1831, we were one morning absolutely enveloped in an atmosphere of gossamer, which not only carpeted the ground, but rose to the height of thirty or forty feet, and which could only have been produced by countless myriads of the little field-spider. Mr Darwin, in his voyage round the globe, noticed thousands of the gossamer-spider on the rigging of his ship. when sixty leagues from any shore; and found other species in abundance on island patches so desolate and remote as Keeling's Isle and St Paul's.

These animals, thus widely distributed, are strictly carnivorous in their habits, feeding only upon prey which they have themselves killed. When they have got an insect between their claws, either by entrapping it in their web, or by their stealthy mode of pursuit, they plunge their poisoned pincers into his body, and the bite is usually soon fatal. Sometimes, however, the insect has strength enough to resist its enemy, and to prevent the infliction of the fatal wound; and as a prolonged struggle might be very injurious to the spider, on account of the softness of its body, it generally retires from the combat, if not speedily successful. Where its prey has been entangled in its web, however, the spider still further encloses it by a thread, and then retires till the insect has exhausted its strength by ineffectual struggles, when it soon despatches its victim. Those species which ensnare their prey by webs are generally termed sedentary spiders; those that seize it by running or leaping, are distinguished as wanderers; and a third group, which, like the second, do not construct webs, but merely fashion a den in which they lie in wait, may be termed lurkers. Their habits, however, will be more fully detailed when we come to speak of particular species. Meanwhile, it may be observed that, though some of them are night or day workers indifferently, the greater number of them are on the chase during the day, when their prey is most abundantly abroad.

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 its body; and so fatal is this operation, that a few seconds terminate

last.' The young of some species are fed for a short while by the parent; but the majority, we believe, shift for themselves on leaving the envelope, and soon arrive at maturity.

Thrown early on their own resources, the young spiders commence a solitary life, lurking in holes and corners for the prey which may fall within their reach. Everywhere are they seen fabricating their snares in the fields, on trees and shrubs, on the grass, and in the earth; and if we watch their proceedings, we may sometimes see them ascend into the air, where, borne by their webs as by an airballoon, they can elevate themselves to a great height. In this manner they often appear in vast numbers, and at a great distance from land. In 1811, the river Tagus was covered for more than half an hour with their floating webs; and in October 1826, Mr Blackwall found every field and hedge in his neighbourhood covered with a confused network of shining lines, thickly coating his feet and ankles as he walked across a pasture. In the autumn of 1831, we were one morning absolutely enveloped in an atmosphere of gossamer, which not only carpeted the ground, but rose to the height of thirty or forty feet, and which could only have been produced by countless myriads of the little field-spider. Mr Darwin, in his voyage round the globe, noticed thousands of the gossamer-spider on the rigging of his ship. when sixty leagues from any shore; and found other species in abundance on island patches so desolate and remote as Keeling's Isle and St Paul's.

These animals, thus widely distributed, are strictly carnivorous in their habits, feeding only upon prey which they have themselves killed. When they have got an insect between their claws, either by entrapping it in their web, or by their stealthy mode of pursuit, they plunge their poisoned pincers into his body, and the bite is usually soon fatal. Sometimes, however, the insect has strength enough to resist its enemy, and to prevent the infliction of the fatal wound; and as a prolonged struggle might be very injurious to the spider, on account of the softness of its body, it generally retires from the combat, if not speedily successful. Where its prey has been entangled in its web, however, the spider still further encloses it by a thread, and then retires till the insect has exhausted its strength by ineffectual struggles, when it soon despatches its victim. Those species which ensnare their prey by webs are generally termed sedentary spiders; those that seize it by running or leaping, are distinguished as wanderers; and a third group, which, like the second, do not construct webs, but merely fashion a den in which they lie in wait, may be termed lurkers. Their habits, however, will be more fully detailed when we come to speak of particular species. Meanwhile, it may be observed that, though some of them are night or day workers indifferently, the greater number of them are on the chase during the day, when their prey is most abundantly abroad.

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 its body; and so fatal is this operation, that a few seconds terminate

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