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THE SPIDER WORLD

In enlarging the images of these small spiders to many times their size, one is at once struck by their similarity to crabs and lobsters. Their jointed legs encased in shells, which from time to time they shed, remind one strongly of the crabs, and they do in fact belong to the some great family, the family of arthropods, and they are not insects.

The spider world is the world of eight-legged creatures just as the insect world is the world of the six-legged ones, and educated men and women should no more confuse these great classes of beings than they confuse the bipeds with the quadrupeds.

They differ from the insects in other ways than in the number of their legs—they have no feelers or antennæ, those wonderful sense organs which all insects have, but here and there, especially on the legs, are strange hollow bristles or spines, which end in nerves. Their eyes also are not like insects’ eyes. An insect’s eyes, at least its large prominent ones, are composed of hundreds of lenses or facets, while the spider, though he generally boasts of eight, has only simple ones with single lenses.

Their life is very simple as compared with that of many of the insects. In the fall, the mother spiders lay their eggs in a bag of their own silk, often several hundred eggs being laid in one sac. The spiderlings hatch out in the sac, and, in the North, they spend the long winter there.

They do not have two stages of existence as beetles or butterflies do, but are hatched out mature and equipped with the poison fangs which aid them in their strictly carnivorous, and often even cannibalistic, existence.

They grow and shed their skins as do the baby grasshoppers, but they do not change their form with each moult and none of them have wings.

They have inside their bodies, reservoirs of strange, sticky fluids which they can pour out through spigots in many different ways. This fluid, as it dries, may form drag lines which they trail behind them and fasten as they go to use for safety lines; with some spiders it may even be poured out in such quantities that it makes an aeroplane; with the majority, however, it is used to make their nests or their egg sacs or the marvelously beautiful orbs that prove the graveyards of so many careless insects. For the spiders are the enemies of the insect world; were they more discriminating, they would be perhaps the greatest friends of the human race, but, as they suck all kinds of insects’ blood, all that we can be sure of is that those among them which we find in our houses are a benefit, for there they kill the flies and other insects which we do not want indoors.

To their Southern and especially their tropical cousins, which attack and sometimes kill human beings, this group of fascinating creatures owes the dread in which it is held by people in general. It is a pity, for throughout the Northern states, no dangerous species is known to exist, and those which frequent our houses will no more attack us than do the flies they catch and devour.

Until a child has gazed in wonder at an orb weaver as it spins its web between the trees, or been an eye-witness of the death of some insect unlucky enough to fall into a web, he has not taken his first step toward the wonderland which touches him on every side and he is in grave danger of growing up with a blind side—the side turned toward the field and forest.

There are millions upon millions of spiders, and thousands of species, and they live everywhere from the Arctic Regions to the Tropics. They devour countless myriads of flies and gnats and hosts of other insects, and nobody knows just what good they do us, but every entomologist would hold up his hands in fear at what the result might be should the spiders of the world be blotted out. They must hold countless parasites in check and help to keep the balance even.

If all the little children should learn that they are harmless, I wonder if they could not stop their nurses from killing them. It is the ignorance of those who train our little ones that keeps alive the unreasoning hatred towards so many of the wonder creatures of the woods.

AN EIGHT EYED ENEMY OF THE FLY; A JUMPING SPIDER

(Phidippus audax, Hentz)

We are so accustomed to beasts with two eyes that it is hard to realize that all around us, though hard to see, are little monsters with many eyes of various sizes.

This one has eight eyes, four of which are invisible from the front. The eyes are diurnal, enabling the creature to hunt only by day. Its eight stout legs fit it for jumping forward or sideways with great ease. In comparison with its size, its jumping powers are incredible. If it were the size of a tiger, it would be a beast of prey which could clear a quarter of a mile at a bound.

It can sit on a branch and throw out an elastic dragline behind, strong enough to bear its weight, and by this means it is able to jump at and catch its prey on the fly, regaining its position by climbing up the dragline. Add to this that it possesses a pair of powerful hollow fangs, into which poison sacs empty, and a voraciousness which often leads it into cannibalism, and you have a fair picture of this jumping spider, which is one of a thousand species of little creatures found everywhere except in the polar regions. They range in size from a third to a half an inch long and live under stones and sticks, spending the winter in a silken bag of their own manufacture, but never spinning a web. The males of some species have been observed to dance before the females, holding up their hairy legs above their heads apparently to show off their ornamentation.

READY TO POUNCE ON A FLY ON THE WING; THE JUMPING SPIDER

These is something diabolical in the way these four black eyes in a row stare one out of countenance.

A JUMPING SPIDER READY TO SPRING FROM A LEAF

(Phidippus togatus, Koch.)

I must confess to a peculiar feeling of embarrassment, almost of fear, towards a jumping spider. It stares at you so intently and seems no fearless as it wheels to keep you covered with its battery of eyes; and you never know which way it is going to jump.

THE WOLF-SPIDER

(Lycosa carolinensis, Walck.)

This is not the photograph of a polar bear, but that of a wolf-spider, with a battery of eight eyes on the top of its head and poison fangs hanging below.

Some such impression as this, I imagine, must be made on the retina of a fly or beetle when, in wandering through the grass at dusk, it suddenly finds itself face to face with a wolf-spider sitting on the turret which forms the entrance to its web-lined hole in the ground.

Behind and above the fangs and hidden in their shadow is the creature’s mouth, toothless and made for sucking only. With his fangs, this wolf-spider kills and crushes his victim; then he sucks the body dry and throws away the carcass.

Seen here and there above the body hairs are black spines, hollow inside and connected with the nerves of touch. Of his eyes, the two in the center in front are supposed to be for use by day, while all the others are nocturnal, enabling him to stalk his prey at dusk. It is the wolf-spider that often appears at night within the circle of lamplight searching for nocturnal insects.

The nocturnal eyes are remarkable organs, with reflecting structures so placed behind the retina that the light entering the eye traverses the retina twice, and it is supposed that this reflecting structure increases the effect of any faint light, enabling the creature to “see in the dark.”

This is a hunting spider, chasing its prey through the grass or lurking under stones, especially in damp places.

It does not spin a web, but lives in a silk-lined hole six or eight inches deep, which it digs in the ground, and around the entrance to which, out of sticks and grass, it builds a turret or watch-tower, from which it can see its prey more readily than from the ground. These spider holes are common in the meadows of Maryland.

In form and color the wolf-spider resembles the famous tarantula of southern Europe, the bite of which was supposed to cause the tarantella, or dancing madness; but it is as harmless as a butterfly, and indeed, Doctor Comstock, who is the authority on spiders, believes that no spiders in the Northern states are poisonous to man.

THE CAST OFF OUTER SKELETON OF A WOLF-SPIDER

(Lycosa punctulata, Hentz)

This photograph is of the outer skeleton or shell of a small wolf-spider which I found clinging to the focusing cloth of my camera after it had been lying on the grass.

With us the bony skeleton is internal and grows as we grow. With spiders the skeleton is a tough, leathery structure, which cannot change; so that the young, rapidly growing spider soon finds his shell too tight for him, and, like a crab, he bursts his shell and pulls his soft body from each leg and complicated cavity.

This process seems marvelous, but is really comparatively simple when we realize that before the old shell is cast off it is loosened from the new skin by the moulting fluid which is excreted from glands opening through this new skin.

After the old skin is loosened it splits along the sides of the body and in front of the eyes, the slit being just above the legs and jaws, and that portion of the old skeleton which had covered the back is lifted off like a lid. The new skin, at first elastic enough to accommodate the increased size of the body, soon becomes hardened like the old, and must in its turn be shed.

Imagine, if you can, the surprise of a wolf-spider who, in running through the grass, should stumble over his own outgrown skeleton, so like his former self in all its details that he could scarcely fail to recognize it as his own; for even the transparent cornea of the eye is a part of this outer skeleton and is shed with it, as well as the jaws, sensitive spines, and hairs.

THE SPINY-BELLIED SPIDER WHICH BUILDS NETS ACROSS THE PATH

(Acrosoma gracile, Walck.)

We are accustomed to the dromedary’s hump and the kangaroo’s big tail, but had this creature been as big as either, or were we Lilliputians, its black and white spiny body, shaped at the bottom like an umbrella stand, would attract more attention at the zoo than either of those desert beasts.

Its eight long, crab-like legs are made for spinning, and across the openings in the forest it stretches a great net in which to snare its game. On this it sits protected from the birds to whose eyes it looks from above like some bird’s droppings in the web. This one is a female and its mate is said to be much smaller and quite different, with no humps or spines at all and a long narrow body.

The courtship of spiders is often a dangerous business for the male, and perhaps it is quite as well for him that he is often smaller and more agile than his mate, for if the female is not ready to receive his advances, she is apt to pounce upon him and destroy him.

THE BIRD-DROPPING SPIDER, A CREATURE WITH PROTECTIVE COLORING

(Epeira verrucosa, Hentz)

This orb weaver had swung its net across a wood road, and so perfectly did the white patch on its back resemble a bird’s dropping that until my hand touched the net I failed to realize that a living thing was hanging there. There is something strangely fascinating about the compelling force of instinct: a spider hatched in captivity who has never seen a web made, will weave its own in the same delicate and intricate pattern that its mother made, using the different kinds of rope correctly, and spacing each strand with a mathematical precision. Indeed, the web of this untutored little spiderling will be as characteristic of its species as the white spot upon its back. It would be as though a child, cast alone on a desert island, should build a house in all details precisely like its ancestral home.

THE AERIAL TRAPPER: THE ORB-WEAVING SPIDER

(Epeira trivittata, Keys.)

Hidden behind these eight four-jointed legs of varying lengths, covered with hollow, sensitive bristles, is the spider’s head, with eight eyes, strong jaws, poison fangs, and a pair of palpi, which look like extremely short legs and seem to serve as hands. The hairy body is filled with thousands of eggs and contains also a marvelous reservoir of liquid rope opening into spinnerets on the under side of the body. Some of the tubes or spinnerets make strong and dry filaments and others make sticky ones. The radiating threads of the spider’s web, those which compose the framework, are stiff and dry; the spiral threads, however, which join them together, are coated with a substance which no little flying creature can strike against without running the risk of sticking fast.

Before you are up on a summer’s morning this wonderful creature will have manufactured what would be equivalent to two miles of elastic and sticky rope if she were as large as a six-foot man. With the skill of an experienced fish-net maker, she will, in a few hours, construct a net as large as a cartwheel, which like the whale-nets of New Zealand, though they may break with the floundering of the prey, bewilder it and tire it out with struggling.

The orb-weaver is the aerial trapper among living creatures, stretching its sticky, elastic web across the aerial runway of its prey and waiting with a patience which would drive a fisherman insane.

To insects of its own size, the orb-weaver is a hideous, bloodthirsty monster. It sinks its fangs into its struggling prey, injects a poison quite as deadly as that of the rattlesnake, and quickly sucks the blood of its victim.

ORB-WEAVER FILLED WITH A THOUSAND EGGS WHICH SHE LAYS ALL AT ONCE

(Epeira domiciliorum, Hentz)

Atlas with the world on his back, as imagined by the boys of Athens, could not have been more strange than this creature with her distended yellow body.

Some of her kin have fasting powers almost beyond belief; they have been kept alive in captivity for eighteen months without food.

This species is one of the commonest orb-weavers on the American continent, and its webs, like great cartwheels, are to be found across the pathways in the woods and everywhere in clearings in the wood-lot.

She is a tight-rope performer her whole life long and her long, muscular legs seem well fitted to enable her to hang, week after week, from her web, supporting in her much enlarged body a thousand or so eggs, which she will later lay, not one at a time, but all at once. No surprise is sudden enough to catch her unprepared and make her fall from the dizzy heights where she lives, without first being able to attach an anchor line. This she does by rubbing her spinnerets over the surface on which she stands, and by quickly spreading and bringing them together again she makes an attachment disc from which she can reel out her rope and check her fall.

The gift of spinning from internal reservoirs, supplied by active secreting cells, is common in the insect world as well as in the world of spiders, for thousands of species of caterpillars make cocoons of silk which they spin as rapidly as any spider makes its web. I doubt if any silk-gowned lady ever stops to think how many thousand gorgeous moths have been cut short in their careers in order that the threads which the silkworms have thrown around them to make a nest in which to pupate could be reeled off to make the silken stuff she wears.

A SPIDER FROM A FLY’S POINT OF VIEW

(Dolomedes tenebrosus, Hentz)

A spider from the fly’s point of view is a terrible monster, indeed. Its claws of polished chitin, sharp as sword points, each with an aperture leading to a sac filled with deadly poison, its array of eyes of different sizes, its mottled, hairy skin covered with hollow sensitive bristles, and its powerful, leg-like palpi must strike terror to the heart of any fly or cockroach which may happen in its neighborhood.

Civilized man rarely sees the ferocity of wild beasts displayed, for even in the jungle it is hard to observe. To anyone, however, who will watch a spider devour a fly, the true picture of merciless cruelty will be apparent. With its poisoned sword-like fangs it kills its prey, and then, with its sucking mouthparts, it sucks the juice out of the carcass.