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 gra.s.s, 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.

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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.

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THE BIRD-DROPPING SPIDER, A CREATURE WITH PROTECTIVE COLORING

(_Epeira verrucosa_, Hentz)

This...o...b..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 s.p.a.cing 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.

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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.

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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 coc.o.o.ns 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.

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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 c.o.c.kroach 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 carca.s.s.

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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 ma.s.s of silk.

In these nurseries the strong eat up the weak.

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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.

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THE MALE GRa.s.s SPIDER