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tubes, having solid walls, and the end truncated with a membranous surface, riddled with holes. By these microscopic openings escapes the liquid which, hardened in contact with the air, becomes the thread out of which the web and the cocoon are made. Although it is cited as the type of fineness, this thread is formed of several fibers, which adhere together on issuing from the spinneret. It is unrivaled for evenness, delicacy, and power of resistance.

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The internal organization of the spider is even more admirable than the external parts. It would be hardly possible even to point out in this paper the most essential features of it. It would be going into long details to describe a muscular apparatus having a power of which the animal kingdom affords few examples, assuring wonderful precision and agility in movement; a nervous system whose enormous development accounts for faculties of a superior order; and a stomach of construction peculiarly adapted 1. Under part of a spider's body-t, the thorax

They

2.

FIG. 1.-PARTS OF A SPIDER.

or chest, from which the eight legs spring, and to which the head is united in one piece; f, fangs; p, palpi or feelers attached to the jaws; a, abdomen; b, breathing slite; 8, six spinnerets, with thread coming from them.

Front of spider's head-e, eyes; p, palpi ; l, front legs; h, hasp of fangs; f, poison fangs; j, outer jaws.

to a diet composed exclusively of fluids. It is written that spiders breathe by lungs. They have an aërial respiration, but it is by organs very different in structure from the lungs of man. consist of minute pockets containing flattened sacks packed like the leaves of a book, through the walls of which the blood infiltrates, and the interior of which is penetrated by the air. Thus observed under water, the little sacks appear like so many sheets of silver communicating with the outside by slits at the bottom of the belly. Spiders have also a heart and a circulation of blood of the most complex character. The heart, which is on the dorsal face, is of an ideal anatomical structure, and long evaded the attempts of investigators to discover the vessels that carry the blood to the periphery of the body. The main vessels were finally traced out by means of colored injections in the European species, and the smaller ones afterward in the larger South American species. The study was a most charming one to

the young naturalist who made it about forty years ago, revealing a beautiful force-pump action, executed by instruments of infinite delicacy, and a power with which no machine of human invention can be compared.

Spiders are generally very prolific; yet we never see their numbers increasing considerably in any country. Fecundity is always proportioned to the dangers that threaten individuals. The young of these creatures so skilled in spreading nets are tempting bits to the appetites of carnivorous birds. All the spiders lay eggs, the larvæ from which have already the form and aspect of their parents. While as mothers they are incomparably careful, vigilant, and devoted, spiders show no feeling except for their own progeny. From the moment the young are in a condition to leave their mother, they become isolated from one another. When not under the influence of maternal instincts, the spider lives only for herself, ignoring the existence of every other individual of her race, which she devours pitilessly whenever she finds one within her reach. In such a world there are, in fact, no loves. The females are believed to be absolutely indifferent. If a male desires to contract a marriage, he proceeds with unexampled precautions, as if he knew he would be ill received. At last, if he is adroit, he will enjoy an embrace of an instant, and then, making the best use of his legs, which are longer than those of his ferocious spouse, he gets away as quickly as possible, otherwise his relative weakness would make him a victim. Poor male spider! He can not know the joys of paternity, but he can doubtless renew again and again his short instants of pleasure, for the two sexes are represented in the most unequal manner, the females being ten or twenty times as numerous as the males. The facts just related apply to spiders in general. But the various types furnish examples of special industries, aptitudes, and manners, on account of which it is necessary to divide our subject into special histories.

On the edge of the forest, among the rough-barked trees, or in dilapidated walls in the open fields, one may see in hot, sunshiny days numerous little spiders, scattered singly or gathered in groups, among which no hostility is manifested. Parts of their bodies are sometimes glossy and brightly colored, sometimes adorned with regular and elegant designs, forming a fine white, yellow, or red pubescence. They are extremely lively, and seek the brightest light. If the amateur tries to catch one he will be disappointed, for it will escape him and get out of the way at a bound. These spiders, jumpers, belong to the group which naturalists call the saltatory spiders (Fig. 2). Some of them are disguised, as if for protective resemblance, with the costume of a hymenopterous insect, or under an aspect resembling that of ants. Producing

only a small quantity of silk, they hide themselves in cracks in the walls or in fissures of bark in the shadow of the foliage, and make themselves a lodge out of a smooth or flossy tissue. At the laying of its eggs, the jumper shuts itself up in its shell. One species deposits its eggs without any covering; a more fortunate species incloses them in a sack with thin and almost diapha

SPIDER (Altus familiaris).

nous walls. Not having the faculty of spinning FIG. 2.-JUMPING webs, the saltatory spiders are hunters, and have to fast if the weather is bad. On pleasant days they are to be found all around, and, having eyes all over the cephalic region, some of them quite small and others of enormous size, they can look accurately through all the surrounding space, which they explore slowly and with care. If a fly is in sight, the spider lances itself upon it with dizzy rapidity. It measures its distance so well that it rarely misses; but, if this should happen, no harm comes to it, for it has fixed a thread to its starting-point, which, unrolling as it leaps, prevents its striking upon the ground, and affords an easy road back to its position.

Some spiders are wealthy, having at their disposal an immense quantity of textile matter, which is renewed continually; others produce but little, and have to live in cells under stones or dead

[graphic][graphic]

FIG. 3.-WOLF SPIDER (Lycos fertifera). FIG. 4.-HUNTING SPIDER (Dolomedes mirabilis),

with a bag of eggs, d.

They have to hunt the water, or among

leaves, in the cracks of trees, and in walls. their game in the fields, along the edges of aquatic plants. They are the Lycosa (Fig. 3). The smaller, darkcolored species of central Europe have little to attract the eye; but occasionally the attention of the careful observer is directed

to one which is running rapidly along the road or trying to hide itself in the grass. It is carrying a pure white, round shell-the sack containing the eggs-in making which it has expended all the silk it had (Fig. 4). A mother of incomparable vigilance, homeless, its eggs laid and well protected in the silky walls of the shell, it does not abandon the cradle of its offspring for an instant. If we succeed in seizing one of the animals during its journey and take away its cocoon, the spider, usually so timid, instead of running away, makes a show of fight against the aggressor. If the cocoon is on the ground, it makes most earnest efforts to take it up and run away as quickly as possible. As soon as the young are hatched they attach themselves to the body of their mother, and she carries them till they are strong enough to hunt a prey, crafty enough to deceive an enemy, and ungrateful enough to cease to recognize a mother whose care has become of no use to them. Large lycosas adorned with lively colors inhabit southern Europe, Africa, and some parts of Asia. They are wanderers like their congeners of cold and temperate countries, and have the advantage over them of a longer existence and of having fixed retreats. They dig a cell in the ground, tapestry its walls, and weave a barricade of crossed threads across the entrance. Among them is the tarantula, concerning the effect of whose bite many marvelous but fictitious stories are told.

The smaller rivers of Europe are inhabited by an aquatic spider, the Argyronetus aquaticus, the first observation of which was a considerable surprise to the Père de Lignac, who discovered it and first described it. It was in 1747, and he was bathing in a river near Mans, when, he relates, "I was surprised by a wonderful sight: bubbles of air, bright as polished silver, appeared to swim around me and follow me. Their free movements, which were not determined by the motion of the water or by the levity of the air, declared that they were animated. My surprise shortly became astonishment when I perceived that they were large spiders whose bodies were enveloped in air." Two years afterward, Lignac obtained several specimens of the argyronetus, and made a closer study of them. While their nearly constant abode is the water, they are, like most other spiders, air-breathers; consequently they need some special provision for providing themselves with air while living under the water, and for this purpose they possess the art of constructing a kind of diving-bell. It is an interesting sight to witness one of them making his air-cell. Clinging to the lower side of a few leaves, and securing them in position by spinning a few threads, the spider rises to the level of the water, with its belly uppermost, and, doubling up its hind-legs, retains a stratum of air among the hairs with which its body is covered. Then it plunges into the water and appears as in the

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first stage of the making of its silvery robe. Going immediately to the spot it had chosen, it brushes its body with its paws, when the air detaches itself and forms a bubble under the leaf. The

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spider surrounds this bubble with the impermeable silky matter furnished by its spinneret. Returning to the surface, it takes in another layer of air, which it carries down and adds to the first

VOL. XXXIII.-51

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