  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. 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. THE MOTHER SPIDER AND HER NEST: A NURSERY OF LITTLE CANNIBALS This mother belongs to the nursery-web weavers. She wove a silken bag for her eggs and carried it about with her under her body until she found a suitable place to leave it. She had to stand on tiptoes to prevent its dragging—it was so big. The photograph shows the spiderlings hatched and running about, hundreds of them, over the fine-spun mass of silk. In these nurseries the strong eat up the weak. A VAGABOND SPIDER (Pardosa milvina, Hentz) This is a vagabond of the spider world, building no nest or web, content to use her marvelous silk in the construction only of a sac in which to lay her eggs. This sac she carries about with her until the eggs have hatched and the spiderlings are strong enough to take care of themselves, and then she rips open the sac along a distinct seam on the edge and turns her babies loose to shift for themselves. These voracious little cannibals have, however, already learned to forage, as the struggle for existence in many species of spiders begins in the egg sac, and it is only the strongest who emerge. In other words, they eat each other up. They do not grow to be more than half an inch in length, but they are among the most active of all spiders, and in the United States alone there are nearly a score of species of these little soldiers of fortune living nowhere and roaming the damp fields in search of prey. THE MALE GRASS SPIDER (Agelina nÆvia, Walck.) On a summer morning, if you rise with the sun, and if the night has been cool, you will find your lawn covered with most exquisite shimmering gossamer patches, so diaphanous that if you touch them or breathe on them they fade away. These are the webs of the young grass spiders and, if you watch one of them closely, you will see that the tiny spider is waiting below the web in a funnel of woven spider’s silk. It will run out quickly enough if you throw a fly into its net. It is not an orb-weaver and runs over its net instead of climbing along the under side of it as many orb-weavers do. That this is the photograph of a mature male is evident from the genital palpi, resembling a pair of short front legs. In the autumn the males and females both desert their webs to wander, for it is not only their mating season but the close of their brief existence. Under a bit of bark the female lays her eggs and waits for death, guarding her progeny till she dies, although she has no hope of seeing them alive. How, by what marvelous machinery, do these microscopic eggs beneath the bark inherit, not only the color and the form but the knowledge of web building which their dead parents possessed? Is there not something wrong in our idea of the individual as a separate thing rather than as a transitory part of a living network which has been in existence perhaps a million years, alternating in its form, now as a moving hairy-legged thing, and now as a round immobile egg? THE CRAB SPIDER THAT LURKS AROUND THE NECTARIES OF FLOWERS (Xysticus gulosus, Keys.) Like the beasts of prey which lurk around the water holes of African deserts, waiting for the feebler game to come down to drink, the crab spiders conceal themselves around the nectar-bearing discs of flowers. These nectar cups are the feeding places of thousands of sucking creatures, and the tragedies which take place in the shadows of the rose or lily petals are things we do not like to think of, for they are quite as real, quite as horrible and bloody struggles as those upon a larger scale, the very thought of which makes our blood run cold. The crab spiders cannot run forward but dart sidewise and backward at great speed. One cannot help wondering if this ability may not often be an advantage rather than a drawback and enable the creature to surprise its prey by turning its back on it, something as a left-handed man often surprises an antagonist. That these spiders run their own grave risks in this life around the nectar “water holes” is evident, for they form a large proportion of the food of mud wasps and if you want a handful of them, tear down a few mud daubers’ nests sometime in June and empty out their contents. The brilliant colors will surprise you and suggest that possibly the yellow ones haunt the yellow flowers and the blue the blue ones. The particular species whose low, sprawling form is shown in the photograph is one of forty occurring in the United States and, although it is only from a fourth to a third of an inch long, is considered one of the large species. It is dull-colored, and, unlike its gaily-colored relatives, awaits its prey under bark and stones. It spins no web and the small male leads a thoroughly vagabond life, whereas the female, in most species at least, settles down toward the end of her life and, after depositing her silken lens-shaped sac of eggs in some protected spot, she lingers near as if to guard it till she dies. A FRONT VIEW OF A MATURE MALE SPIDER The reason for existence is so perplexing that it is no wonder we fall back on mysticism whenever we try to explain it. Inexplicable as it seems when we consider our own lot as humans, the mystery is no less great when we try to view existence from the standpoint of a male spider. Is it not probable that we cling so dearly to the idea of our own existence as individuals that we forget we are only halves of a whole, and that the whole itself is only a fraction of that vague living something spread out over the earth, moving in millions of places at once which we call a living species? When we shall have shifted our sympathies and made them cover a thousand generations of beings, we shall have risen to the point of view that a divinity must take. The enigmas of existence, I venture to say, will only be understood from this standpoint and not from the more sympathetic one of regret over the shortness, cruelty or barrenness of any individual’s life. The male spider seems peculiarly to be just a tool in the machinery of descent, merely a carrier of the male germ cells which, whenever, and not before, they come in contact with their female counterparts, start into activity the marvelous growth which results in new individuals similar to itself. These male cells which form within its body, mature, and are ejected as living, ciliated things into a web of special make; and two special syringes formed late in life at the tips of the leg-like palpi draw them up and hold them stored until it is time for them to be injected during the mating process into special sacs within the female, where they fuse in some strange way with female cells and start the following generation. His palpi once emptied of these male cells, of what further use to the species can he be and why should not the carnivorous female promptly eat him up? THE DADDY-LONG-LEGS OR HARVESTMAN (Leiobunum grande, Weed) Who has not watched daddy-long-legs stalk majestically across the floor or up the wall, one long slender leg waving in front of him like the arm of some gesticulating prophet of old? Indeed, the fly or mosquito is hardly more familiar. Long-leggedness is all relative to size of body, and viewed from this standpoint everyone must agree that the harvestman is the longest-legged creature in the world. If its body were the size of a flamingo its legs would cover over thirty feet of ground. As it has eight legs and each leg is eight times the length of its body it has sixty-four times as much length of leg as of body. It is a strange, spider creature having only two eyes which look to right and left from a turret-like hump in the middle of its back. Its claws in front have pincers like a crab’s. Opposite the first pair of legs are scent glands from which it pours out a fluid which has so bad an odor that it seems to protect it from its foes. Swung low between its legs, this creature of twilight and shade wanders in search of small insects which it catches and devours as other spiders do. It only lives one season in the North and spins no web and makes no nest. The female lays her eggs deep down in the ground or under stones or in the crevices of the bark of trees. |
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