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Leapers of all kinds are liable to falls; and to prevent accidents from this source, nature has been very beneficent in her endowments. The cat kind invariably alight on their feet, let the height from which they fall be what it may; the impetus of the grasshopper is broken by the spread of her sheaths; and the hunting spiders throw out a cable, by which they dangle in the air, and can speedily recover their original position.

WANDERING SPIDERS.

The common wandering spider (Aranea viatica) is an active, lively hunter, which may be said to run down its game rather than lie in wait for or ensnare it. It is ever on the move, and, being remarkably quick-sighted, is not long in discovering its game, which it grasps in its feathered arms. Occasionally it seizes a fly stronger than itself, and then the two may be seen rolling and tumbling about-the spider holding on with convulsive grasp, and the fly struggling and buzzing in an agony of terror. The struggle is usually soon over; for what the spider wants in mere bodily strength, is more than made up for by his poisoned fangs, which are sunk at the first opportunity into the breast of his victim. There are numerous species of wanderers, all rather large, and beautifully marked--the ground colour being generally tawny, and the linear bands of orange and changing green, with small black dots between. It is asserted by some that they sit on their eggs, and by others that they carry them about in little balls, like the epeira. Both assertions we doubt they may watch beside their eggs, but assuredly they do not sit on them for the purpose of hatching; and the dragging of a ball behind them for three weeks or more, would be destructive of their capabilities as hunters. We believe that they make use of a fixed envelope of web, as many other of the field-spiders do, and trust to the natural warmth of the season for the development of their brood.

THE GOSSAMER-SPIDER.

One

Though perhaps the smallest, gossamer-spiders are among the most active and most widely distributed of the tribe. In favourable autumns they are found in myriads, scattered everywhere, and borne everywhere on their airy webs-it may be to hundreds or even thousands of miles distant from the spot whence they arose. of the most common of the gossamer-spiders of Europe (Aranea obtextrix) is about the size of a pin's head, and of a shining darkbrown colour, with yellowish legs. These little creatures have the power of shooting out lines of gossamer from their spinnerets, so as to render themselves buoyant in the air; and these lines, being borne upward and onward by aërial currents, float the aëronauts with as

great safety as if they had wings. They can also coil and thicken these lines when in the air; and by this means, as well as by the lines crossing and tangling with each other, showers of cobwebs have been occasioned, which, till the cause was discovered, gave rise to strange suppositions. By one of these showers in September 1741, which extended for many miles, Mr White of Selborne was prevented from hunting, his dogs being blinded and hoodwinked.

These spiders, according to Dr Bechstein, who has closely studied their habits, first appear, towards the end of September, in woods, gardens, and uplands, where their eggs are hatched in safety; thence they spread themselves over whole districts, and during October, and till the middle of November, may be found in dry fields throughout Europe. At that season extensive tracts of land are sometimes seen swarming with them. In the beginning of October, when but few are hatched, some single threads of their webs, extending from twig to twig, are seen only in the sunshine; about the middle of the month, their threads are more perceptible; and towards the end, if a person stand in such a position as to see the sunbeams play on the slender threads, hedges, meadows, corn-fields, stubbleland, and even whole districts, appear covered with a fine spangling silvery gauze. These little animals do not weave webs, but only extend their threads from one place to another. These threads are so delicate, that not one can be seen unless the sun shines upon it. One of them, to be visible at other times, must be composed of at least six ordinary threads combined together. In serene calm days these spiders work with great diligence, especially after the disappearance of the morning fogs. Between twelve and two, however, their industry excites the greatest admiration. A person with a pretty quick eye, or by help of a glass, may sometimes perceive, among the barley-stubble, such a multitude of these insects extending their threads, that the fields appear to be actually alive with them. When several of the single threads become tangled together, so as to form flocks and balls, they are known in Germany by the name of 'the flying summer,' because the summer seems to fly away at the same time. None of the smaller insects can resist this allenveloping mesh of gossamer; and, consequently, aphides, flies, and other spiders may be often seen entangled, and struggling in the

same mass.

It is not in Europe alone, however, that gossamer-spiders abound. Mr Darwin found their lines coating the rigging of the Beagle, when lying within the mouth of the river La Plata, in South America. One day (November 1, 1832) I paid particular attention to this subject. The weather had been fine and clear, and in the morning the air was full of patches of the flocculent web, as on an autumnal day in England. The ship was sixty miles distant from the land, in the direction of a steady, though light breeze. Vast numbers of a small spider, about one-tenth of an inch in length, and of a dusky

red colour, were attached to the webs. There must have been, I should suppose, some thousands on the ship. The little spider, when first coming in contact with the rigging, was always seated on a single thread, and not on the flocculent mass, which seems merely to be produced by the entanglement of the single threads. The spiders were all of one species, but of both sexes, together with young ones. These latter were distinguished by their smaller size and more dusky colour. I will not give the description of this spider, but merely state that it does not appear to be included in any of Latreille's genera. The little aëronaut, as soon as it arrived on board, was very active, running about, sometimes letting itself fall, and then reascending the same thread; sometimes employing itself in making a small and very irregular mesh in the corners between the ropes. It could run with facility on the surface of water. When disturbed, it lifted up its front legs in the attitude of attention. On its first arrival, it appeared very thirsty, and drank eagerly of drops of water; this same circumstance has been observed by Strack. May it not be in consequence of the little insect having passed through a dry and rarefied atmosphere? Its stock of web seemed inexhaustible. While watching some that were suspended by a single thread, I several times observed that the slightest breath of air bore them away out of sight in a horizontal line. On another occasion (25th), under similar circumstances, I repeatedly observed the same kind of small spider, either when placed or having crawled on some little eminence, elevate its abdomen, send forth a thread, and then sail away horizontally, but with a rapidity which was quite unaccountable. I thought I could perceive that the spider, before performing the above preparatory steps, connected its legs together with the most delicate threads, but I am not sure whether this observation was correct.'

The mode in which the web is emitted from the spinnerets of this and other spiders, has given rise to much discussion among naturalists, but we fear to very little accurate observation in the field. Some imagine that it is forcibly ejected from the spinner, so as to shoot forth to a distance of several feet; but these lose sight of the fact, that it is impossible to propel such a light substance, even to the distance of a few inches, unless in vacuo. Others call in the aid of electricity; but this, so far as the animal is concerned, is wholly conjectural, though electrical conditions of the atmosphere may greatly facilitate the ascent of the silken lines. Others, again, and among them Mr Darwin, are of opinion that the creature, highly susceptible of the least current in the air, merely elevates its abdomen, and assists with its limbs the evolution of the gossamer, till the thread is caught by the current, which carries it rapidly onward to the distance of several yards. By the force which the light line of gossamer exerts on the body of the spider, it knows when there is enough to buoy it up; and then quitting hold of the

object on which it stands, it floats away at pleasure. By lengthening this line, it can render the car more buoyant; or by simply coiling it up, or detaching part of it, the little aëronaut can descend on terra firma. Such, we believe, is the right interpretation of the phenomenon, which is one of great interest and curiosity.

THE WATER-SPIDER.

The water-spider (Argyroneta aquatica) is one of our native species, and is found abundantly during summer in our fresh-water ponds and ditches. It is chiefly remarkable for its habitation, which is built in the midst of water, and, in fact, of air—a very uncomfortable one certainly, were it constantly wet; but this the sagacious insect has the means of avoiding, and, by availing itself of some well-known philosophical principles, constructs for itself an apartment, in which it resides in comfort and security. The following is the process: It first spins loose threads, in various directions, to the leaves of water-plants-which may be called the framework of the chamber-and over them spreads a transparent varnish, resembling liquid glass, which issues from the middle of its spinners, and which is so elastic as to be capable of great expansion and contraction. The spider then spreads over its abdomen a little of the same material, and ascends to the surface. The precise mode in which a bubble of air is drawn beneath the gummy matter is not accurately known. Loaded, however, with the material for its little mansion, which to the spectator looks like shining quicksilver, the spider plunges to the bottom, and, with as much dexterity as a chemist transfers gas into a gas-holder, introduces the bubble of air beneath the roof prepared for its reception. This manœuvre is repeated ten or twelve times, until at length, in about a quarter of an hour, as much air is obtained as is sufficient to expand the apartment to its proposed extent, and the industrious little builder now finds itself in possession of a perfect air-tight dwelling, affording a commodious and dry retreat in the very midst of water. Here the inhabitant reposes, unmoved by the storms that agitate the surface of the pool, and devours its prey at ease and in safety. The water-spider becomes dormant during winter, and lodges in empty shells, which it dexterously closes up with a web.

According to Kirby and Spence, a very large aquatic spider, of undetermined species, has often been noticed in the fen-ditches of Norfolk. This creature actually forms a raft, for the purpose of obtaining its prey with greater facility. Keeping its station upon a ball of weeds, about three inches in diameter, probably held together by slight silken cords, it is wafted along the surface of the water upon this floating island, which it quits the moment it sees a drowning insect. The booty thus seized it devours at leisure upon its raft, under which it retires when alarmed by any danger. It

would thus appear that we have not only weavers, trappers, hunters, aëronauts, and divers, but piratical cruisers, that act the part of sea-kings within their little domains.

THE TARANTULA.

This spider-the Aranea tarantula of Linnæus, and the Lycosa tarantula of modern naturalists-is one that can lay claim to something like a classic history, being the source of a superstition very prevalent in Southern Italy. It derives its name from Tarentum, in the neighbourhood of which it was first observed, and is regarded as the most poisonous of the family, its bite being sometimes fatal to man. The following particulars of its natural history are derived from the sketch of M. Leon Dufour, published in 1834. The taran

Tarantula.

tula, or wolf-spider, as it is also called, is chiefly met with in the south of Europe. To understand its manners fully, it is necessary to notice the peculiarities of its structure. The jaws and feet are large and strong; the second joint of the legs, and the first of the feet, are furnished with long stiff spurs, movable at their base, which are of much use to the animal in seizing and holding its prey. The first two pair of feet are furnished underneath with a down, arranged like a brush, which the tarantula employs in making its toilet, and in assisting it to walk on smooth surfaces; finally, the feet are terminated with strong claws. It prefers inhabiting dry arid situations. The cylindrical burrow which it forms is about an inch in diameter, and sunk to the depth of a foot beneath the surface. The construction of this burrow is such as not only to protect the animal from the pursuit of its enemies, but to serve it as an observatory, whence it may dart on its prey. At first the hole sinks perpendicularly, but, at a depth of four or five inches, bends and forms an almost horizontal elbow, after which it again resumes its direction downward. It is just at this bend that the tarantula stands sentry, turning towards the mouth of its den eyes that sparkle and gleam in the dark. The external orifice of the burrow is usually surmounted by a funnel, an inch in height, and two inches in breadth, so that it is wider than the burrow itself -a circumstance that admits of the extension of the claws, necessary to enable the animal to seize its prey. The funnel is composed of pieces of dry wood, united by clay, and lined inside with a web, which is continued throughout the whole interior of the burrow. The utility of this is obvious, in preserving the hole clean, preventing the falling-in of earth, and enabling the spider, by its claws, quickly to ascend.

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