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but the tight trim legs of the spider stand up, and are
, as tough as wire, and in their action as nimble as thought. The flat end of the spider's leg is its foot; the ends of some of its feet are tipped with hooks, while others are lined with fine short hairs, that make a soft brush; this brush is said to be the cause of enabling spiders to walk on ceilings, and to run up walls.
The spider has jaw-feet on its head. In some spiders a few of these jaw-feet are tipped with sharp hooks; and in other spiders they are tipped with pincers, resembling crab's claws. The microscope shews us, that at the end of these hooks or pincers, there is a little hole, from out of which flows the very least drop of poison, and this enters the wound made in any captured insect.
Spiders are intended to live upon flies, moths, and gnats, just as we are intended to live upon vegetables, fish, meat, and fowls : therefore, the spider must catch these insects, and afterwards kill them; and I cannot tell you how delighted I was, when I found that our
Ι kind Creator had given the spider an instrument which is beautifully contrived for quickly putting its poor harmless captives out of suffering. I used to think, when a fly kicked and bounced about in a web, that it was in great pain. I was afraid the spider had begun to eat it up alive; but now I find that when the fly makes such an uproar, it is chiefly because it does not like to be entangled in the web. When a small fly is caught, the spider runs along the fine threads of its web, darts its hook or pincers into the body, and then goes away. In a few minutes, and sometimes even in a few moments, this poison kills the fly.
If the spider finds that a large fly is caught, and fears that its bouncing about will break the web, the spider quickly bites through the threads that are close to the fly, and lets it go away. But if another fly, not quite 80 large, tries to fight the spider with its legs and wings, then the wary fellow spins a little more web out of its own body, and throws these threads over the fly. When
the spider finds that this silken cordage has well bound down the rebellious captive, off it runs to some quiet corner, and there waits till the poor fly has fairly tired itself out with struggling: as soon as it has become quiet, the watchful spider runs along the net, and darts its jaw-feet into the body. The poison in its hooks shortly kills the prisoner; and then the spider comes back, and lifting the fly out of the web, carries it away, to dine upon it in a snug corner close by.
The spider poison is strong enough to kill insects, but on our skin it only produces the same feeling as the bite of a gnat; generally it is not even strong enough to make the part swell up: yet a bite from some kinds of large spiders in hot countries, will occasionally bring on fever. Spiders can live a long time without eating. For days together no fly may be caught: yet they will patiently sit and watch for the movement of their webs. They have even been shut up in tight boxes for six months without food. This long fast made them very thin, but one good meal began to plump them up again.
Crabs and lobsters cast off their old shells, and new ones soon grow over their soft bodies. Spiders also shed their coats; that is, they moult or change their skins. When the old skin is going to fall off a spider, a crack may be seen on the stomach; and through this crack the spider draws out its limbs, and often leaves its old coat hanging in the web.
The spider has several brilliant and sharp-seeing eyes, which are said to shine in the dark, and to have
the power of seeing by night. Sometimes the spider has four eyes, sometimes eight or ten. These eyes never move, but they are like round specks of glass, set in rows on the top of the head.
One of the most remarkable things belonging to the spider's history, is the beautiful silk which it is able to spin out of its own body. With this silk spiders make webs, line their dwelling-places, and
Top of Spider's Head.
spin bags for enclosing their eggs. So fine is one thread of this silk, that it would take ninety such threads to make one as thick as a silk-worm's; and yet every one of them is composed of four or five thousand lines, which were separately drawn out of the spider's body, and afterwards drawn together.
We shall have to speak more of this silken cordage in our next lesson, which will relate to the house spider.
LESSON 26.-THE HOUSE SPIDER. Magnifying glasses-glasses that make Fragments--pieces broken off (Lat. franan object look larger.
go, I break). Bxquisitely-admirably.
Amicably-in a friendly manner (Lat. Crouches-stoops.
amicus, a friend). WE E are
now to look at the house spider. This spider is an old acquaintance, yet such an one as we are always trying to drive away; for no sooner has the poor little creature spread out its delicate web in our rooms, than in great displeasure we seek to destroy it; seldom even waiting to observe the curious manufacture of its delicate home.
On the abdomen—that is, on the hinder division of the spider's body, there are four, and sometimes six little fleshy knobs, each about the size of a small pin's point. These little points are called spinnerets, and belong to bags of gummy silk in the inside of the spider's body. Very strong magnifying glasses show that each spinneret has a thousand holes in it. When the spider wishes to spin, it lifts up one of its legs, and presses it against its spinnerets. This makes the gummy fluid fall to the little holes; and as the spider draws its legs along the sides of its spinnerets, the silk issues from the holes in delicate fibres or threads. The thousand fibres thus issuing from one spinneret then come together and form a thread; and the instant that the four or six spinnerets have dropped
their separate threads to about the distance of a tenth
part of an inch, the spider, quick as thought, turns up its two little hind legs, which have delicate
hooks upon them, and catching hold of the falling threads, with these hooks it guides them into one coil or rope.
The beautiful little hooks on the spider's feet are as nimble as fingers, and being jagged with small teeth like a saw, they never
miss their hold. Magnified Claws Thus you see, that from its fineness, we of Spider's Foot, with
which it di- never can behold the thread that falls from fibres ; generally one of the spinnerets: it is only when the using only two of threads from all the four or six spinnerets have become united into one rope,
that our eyes see the spider's silken cord. This silken cord is so light, that it easily floats in the air; and yet so exquisitely is it made for strength, that before it breaks it will bear the pressure of a weight six times heavier than the spider that made it. Oh,how busy and how quick must that spider be in uniting its many thousand fibres into one cord! If the spider were slow, the glue upon the fibres would dry before they came together; but this little creature is not idle, it never seems to allow its cords to spoil from want of care.
For a certain time spiders seem able to throw out as much silken gum from their bodies as they please; and they also seem able to make their thread thick or thin, for the web in which they wrap up their eggs is much stronger and whiter than the web they weave for catching insects. When the house spider has found a place she wishes to live in, which is generally some corner of a room, she begins her
One spinneret, with web by pressing all her spinnerets against one of the walls; this causes the four or
its falling fibres
five thousand little holes in her spinnerets to gum down their silken fibres tight to the wall
. This beginning of her cord is not united into one close substance, but its fibres are spread out like the roots of a tree, in order to give the cord she is going to spin a firm hold upon the wall. Directly the silken fibres are tight, the spider moves forward; by this act she draws out more silk, and then her web begins; very soon, however, she stops in her work, and her beautiful little feet, with their hooks, take up the new-made cord, and give it & pull, to see if it have stuck tight; if Fibres of the Spider. she thinks it will hold, she creeps along the wall, spinning her thread as she goes; or else she takes a dart across the space between the two walls, and then again presses down her spinnerets on the other side; and turning round, she travels back upon the new-made rope, taking care to fasten another cord upon it, to make it thicker.
The spider is very particular in making her first cord strong; she appears to know that it will be a rim or selvage for the rest of the web to pull against, so she runs backwards and forwards upon it, to double and treble it. When satisfied that the edge of the web is firm, she draws out more lines, and lays them loosely side by side, and often one over the other, until she deems her net is wide and thick enough. This newly-made web is at first rather gummy, so that its threads are apt to stick to the spider's legs as she goes oves it; but to check their drawing up and becoming entangled, she quickly raises a few stiff hairs, which are on the lowest part of her leg, and runs them in between the threads, as if she were using a comb; and having thus smoothed down the disturbed fibres, she very cleverly lays them again on the web.
When the body of the web is finished, the spider will