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antagonist by this appearance. One species, which knew it was being watched, placed itself upon a diseased leaf, where it remained quite stationary until after the departure of the naturalist, who, had he not seen the sidelong movement of the cunning little creature in the first instance, would not have been able to distinguish its body from the surface of the leaf. While, in this case, dulness of color served as a defence, the vividly-colored spiders that live among the foliage and flowers no doubt attract many flies and insects by reason of their gaudily-tinted bodies. An exception to the general rule is, however, found in those very large and powerful species, which, if not rendered somewhat conspicuous to the sight of other insects, might do too much damage to the tribes which they keep in check. Most of these, therefore, have the thorax and abdomen margined with a light color that contrasts strongly with that of their bodies, and, in many cases, gives timely warning of their approach.

The spiders of temperate zones have generally a very repulsive appearance, while many of the tropical species are most splendidly ornamented, or rather illuminated, many of them by the vividness of their colors resembling the gaudy missals painted by monks in the Middle Ages. Thus, among the epeiras of the Philippian isles, are found white figures on a red ground; red, yellow, and black, in alternate streaks; orange marbled with brown, light green with white ocelli, yellow with light brown festoons, or ash-colored and chestnut bodies with crescents, horse-shoes, Chinese characters. and grotesque hieroglyphics of every description. Unfortunately, these colors, lustrous and metallic as the feathers of the humming bird, are, unlike the bright colors of the beetle, totally dependent on the life of the insect which they beautify, so that it is impossible to preserve them. While most spiders obtain their food either by patiently waiting in ambush or by catching it with a bound, the enormous mygales, or trap-door spiders, run about with great speed, in and out, behind and around every object, searching for what they may devour, and from their size and rapid motions exciting the horror of every stranger. Their body, which sometimes attains a length of three inches, while their legs embrace a circle of half a foot in diameter, is covered all over with brown, reddish brown, or black hair, which gives them a funereal appearance, while their long feelers armed with sharp hooks proclaim at once what formidable antagonists they must be to every insect that comes within their reach. Though some species are found in Southern Europe, in Chili, or at the Cape, yet they are chiefly inhabitants of the torrid zone, both in the Old and the New World. Some of them weave cells between the leaves, in the hollows of trees or rocks, while others dig deep tubular holes in the earth, which they cover over with a lid, or rather with a door formed of particles of earth cemented by silken fibres, and closely resembling the surrounding ground. This door or valve is united by a silken hinge to the entrance at its upper side, and is so balanced that, when pushed up, it shuts again by its own weight; nay, what is still more admirable, on the interior side opposite to the hinge a series of little holes may be perceived, into which the mygale introduces its claws to keep it shut, should any enemy endeavor to open it by force. The interior of the nest, which is sometimes nine inches deep, is lined with a double coat of tapestry, the one nearest the wall, which is of a coarser tissue, being covered with a pure white silken substance like paper.

All species of spiders are gifted with the same maternal instinct, and resort to various methods for the purpose of securing their cocoons. The Theridion, when a seizure of the precious burden is threatened, tumbles together with it to the ground,

and remains motionless, while the Thorinsa covers it with its body, and when robbed of it, wanders about disconsolate. In a forest of the Sooloo Islands, Mr. Adams found the ground literally overrun with a small black agile species of Lycosa, many of which had a white flattened globose cocoon affixed to the ends of their abdomen. It was most amusing to watch the care with which these jealous mothers protected the cradles of their little ones, allowing themselves to fall into the hands of the enemy rather than be robbed of the silken nests that contained them.

If the spiders are at war with all other insects, and contribute to keep them within bounds by the destruction they cause among their ranks, they in their turn have to suffer from the attacks of many enemies. Several species of monkeys, squirrels, lizards, tortoises, frogs, and toads catch and devour them wherever they can. In Java and Sumatra, we even find several birds belonging to the order of sparrows that have been named Arachnotheræ, from their living almost exclusively on spiders. Armed with a prodigiously long recurved and slender beak, they know how to pursue them and drag them forth from the most obscure recesses.

It is amongst the insects themselves, however, that the spiders have to fear their most numerous and formidable enemies. Independently of those which they find in their own class, the centipedes seize them beyond the possibility of escape; while several species of philanthus, pompilius, and sphex, more savage and poisonous than themselves, will rush upon spiders eight times their size and weight, and benumbing them with a sting, bear them off to their nests, to serve as food for their larvæ. But the insects which in appearance are the tiniest and most delicate, are perhaps those which most cruelly wound the spiders, by attacking them in their eggs, which they watch over with such affection, as to be ever ready for them to make the sacrifice of their own lives. The Pimpla Arachnitor pierces with its invisible gimlet the tender skin of the spider's egg, and, without tearing it, introduces its own eggs into the liquid. The pimpla's egg soon comes to maturity, and the larva devours the substance of that of the spider, from whence a winged insect bursts forth-a phenomenon which made some naturalists, too hasty to judge from appearances, believe that spiders were able to procreate four-winged flies.

Notwithstanding the disgust or horror which they generally inspire, the spiders are, with very rare exceptions, by no means injurious to man. However promptly their venom may act upon insects, even that of the largest species of Northern Europe produces, on coming into contact with our skin, no pain or inflammation equalling in virulence that of the wasp, the bee, the gnat, or other insects of a still smaller size. The giant spiders of a sunnier sky, armed with more formidable weapons, naturally produce a more painful sting; but even here the effects have been much exaggerated, and the wonderful stories about the Sicilian tarantula's bite, which we read of in Brydone and other authors, are nothing but fables raised upon a very slender foundation of truth. Azara mentions that several of his negroes having been bitten by the large Avicular mygale (M avicalaria) of South America, a slight ephemeral fever was the only result. If thus, among the many species of spiders, hardly a single one may be said to be formidable to man, the indirect services which they render him-by diminishing the number of noxious insects, or keeping in check the legions of gnats which irritate and annoy him by their attacks-are far from inconsiderable. Nor are they entirely without direct use. Several savage nations eat spiders, and the inhabitants of New Cale

donia reckon a large species of Epeira amongst the choicest delicacies of the land. Even in Europe some people enjoy a spider, and the famous astronomer Lalande was far from being singular in this respect. They are said to taste like filberts, and the proper way to eat them is to take off the legs, and to swallow the abdomen, after having washed and rubbed it with butter. The property of spiders' webs to stop an hemorrhage or the bleeding of a wound is a well-known fact, and they have also been recommended as an anti-febrifuge. In several countries where the insects cause great ravages, the services of the spiders are duly appreciated. Thus in the West Indies, a large and formidable trap-door spider, which would make a European start back with horror, is looked upon with pleasure by the islanders of the torrid zone, who respect it as a sacred animal, by no means to be disturbed or harmed, as it delivers them from the cockroaches, which otherwise would overrun their dwellings. Those who do not possess these spiders take good care to purchase and transport them into their houses, expecting from them similar services to those we derive from a good domestic cat.

When we consider the large size of many of the tropical spiders, and the strength of their threads, it seems probable that their cocoons might be put to some use. We are told by Azara, in his "Travels to Paraguay," that a spider exists in that country the silk of whose spherical cocoons, measuring an inch in diameter, is spun on account of its permanent orange color. The eyes and noses of the women employed in unravelling the cocoons are said to water considerably, though without their perceiving any pungent smell, or feeling any other inconvenience. This spider is, perhaps, the same as that which, according to M. de Bomare, is known in the interior of South America under the name of the silk-spider. Its cocoon is of the size of a pigeon's egg, the silk is soft, and can be easily carded. Attempts have also been made in Europe to utilize the threads of the large indigenous spiders. About the beginning of the last century, M. Bon, a Frenchman, who seems to have been the first that ever put the idea into practice, collected a sufficient quantity to make some stockings and gloves, which he presented to the king, Louis XIV., and to the Academy of Sciences in Paris. His discovery caused some sensation at the time, and his dissertation on the subject was translated into all European languages, and at a later period even into the Chinese, by order of the Emperor Kien-Long. The celebrated Reaumur, however, who was commissioned by the Academy to report on M. Bon's discovery, pointed out how difficult it would be to put it to any extensive use, as it would require no less than 55,296 of the Epeira diadema to produce a single pound of silk; and how were all these to be provided with flies?

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If the extreme fineness of the spider's threads is an obstacle to their being spun and woven, this property, united with their metallic brilliancy, renders them an excellent material for the construction of the micrometers used for astronomical purposes: the finest silver thread which it is possible to spin having a diameter of of an inch, while spiders' threads measure only or even . Troughton, an eminent English instrument maker, first thought of substituting them for the silver-threads then in use, and they were found to answer so well that since that time they have been constantly employed.

The Scorpions, which even in Europe are reckoned among the most malignant insects, are truly terrific in the torrid zone, where they frequently attain a length of

six or seven inches. Closely allied to the spiders, their aspect is still more repulsive. Were one of the largest scorpions menacingly to creep up against you, with extended claws and its long articulated sharply-pointed tail projecting over its head, I think, despite the strength of your nerves, you would start back, justly concluding that a creature of such an aspect must necessarily come with the worst intentions. The poison of the scorpion is discharged like that of the snake. Near the tip of the crooked sting, namely, which terminates the tail, we find two or three very small foramina, through which, on pressure, the venom of the gland with which they are connected immediately issues forth. By means of this weapon, even the small European scorpions are able to kill a dog, while the tropical giants of the race inflict wounds that become fatal to man himself. The sting of several South American scorpions produces fever, numbness of the limbs, tumors on the tongue, weakness of the sight, and other nervous symptoms, lasting twenty-four or forty-eight hours; but the African scorpions seem to be still more formidable. Mr. Swainson informs us that the only means of saving the lives of English soldiers who were stung by those of Egypt, was the amputation of the wounded limb; and Professor Ehrenberg, who, while making his researches on the Natural History of the Red Sea, was stung five times by the Androctonus quinquestriatus, and funestus, says he can well believe, from the dreadful pains he suffered, that the poison of these scorpions may become fatal to women and children. A servant of Mr. Russegger, while emptying a trunk, was stung in the breast by a large scorpion, which had concealed itself among the linen. For hours the pain was dreadful, shooting from time to time through the whole nervous system, and almost depriving the patient of consciousness. A cold perspiration covered his brow, and it was only after the internal and external application of ammonia, one of the chief remedies for sustaining the sinking flame of life, that he at length felt some relief, though he had still to suffer several days from a strong fever.

The scorpions live mostly on the ground, in gloomy recesses, and even in the nooks. and corners of dwelling-houses, so that, in countries where they are known to abound, it is necessary to be very cautious in removing stones, pieces of wood, &c. Of a ferocious, cruel disposition, they are not only the foes of all other animals, but carry on a war of extermination among themselves, and are even said to kill and devour their own progeny, without pity, as soon as they are born; thus rendering good service to the community at large. Maupertuis once inclosed a hundred scorpions-a select and delightful party-in a box. Immediately a furious battle ensued—one against all, all against one-and in an hour's time scarcely one of the combatants survived the conflict.

The poison of the scorpion is lodged in its tail, but that of the centipede is in its jaws. These are likewise among the pests of tropical climates; for, although several are found in Europe, yet, from their small size, they are harmless to man. Those of India and South America, on the other hand, are enormous, frequently six or seven inches long, and their sting is no less painful and virulent than that of the dreaded scorpion itself.

CHAPTER X.

SERPENTS-LIZARDS-FROGS AND TOADS.

Serpents: Rarity of Venomous Serpents-Habits and External Characteristics of SerpentsThe Labarri―The Trigonocephalus-Antidotes to the Poison of Serpents-Sucking out the Venom-The Poison-Fangs-The Bush-Master-The Echidna Ocellata- Rattlesnakes -Their Enemy the Hog-The Cobra de Capello-The Haje-The Cerastes-Boas and Pythons-The Boa-constrictor-The Water Boa-Fascination by Snakes-Henderson's Argument against It-Thorpe's Reasons in its Favor-Du Chaillu on the Subject-Enemies of Serpents-The Secretary Bird-The Adjutant Bird -The Mongoos-Serpents Eating Serpents-The Locomotion of Serpents-Anatomy of their Jaws-A Serpentine MealPet Serpents-Tree Snakes-Water Snakes-Stories of Enormous Snakes-Du Chaillu's Big Snake-Wallace's Bigger One.-Lizards: The Geckoe-Anatomy of its Feet-Their Wide Distribution-The Anolis-Its Combativeness-The Chameleon-Its Habits, Change of Color, and Characteristics-The Iguana-The Teju-Water Lizards-Flying Dragons— The Basilisk.-Frogs and Toads: The Pipa Frog-Tree Frogs-Wallace's Flying FrogThe Bahia Toad-The Giant Toad-The Musical Toad.

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N penetrating for the first time into a tropical forest, the traveler is moved by many conflicting emotions. This luxuriance of vegetation, this abundance of blossoms, unite in raising the soul to the fullest enjoyment of the moment; and yet the heart is, at the same time, chilled with vague fears, that mix like a discordant sound with the harmonies of this sylvan world. For in the hollows of the tangled roots and in the dense underwood of the forest a brood of noxious reptiles loves to conceal itself, and who knows whether a snake, armed with poisonous fangs, may not dart forth from the rustling foliage. Gradually, however, these reflections wear away, and time and experience convince one that the snakes in the tropical woods are hardly more to be feared than in our own forests. These reptiles are, indeed, far from being of so frequent occurrence as is generally believed; and on meeting with a snake, there is every probability of its belonging to some harmless species, which show themselves much more frequently by day, and are by far more numerous. Even in India and Ceylon, where serpents are said to abound, they make their appearance so cautiously that the surprise of long residents is invariably expressed at the rarity with which they are to be seen. Dr. Russell, who particularly studied the serpents of India, found that, out of forty-three species which he himself examined, not more than seven were found to possess poisonous fangs; and Davy, whose attention was carefully directed to the snakes of Ceylon. came to the conclusion that but four out of the twenty species he could collect were venomous, and that of these only two were capable of inflicting a wound likely to be fatal to man.

Sir E. Tennent, who frequently performed journeys of two to five hundred miles through the jungle without seeing a single snake, never heard, during his long resi

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