Puslapio vaizdai
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GILA MONSTERS – POISONOUS LIZARDS. mechanism which enables the serpent to use its thrown up in numbers into the paddle-wheel poison.

covers of the old side-wheel steamers. I never We have in America as venomous serpents had the good luck to get a living specimen. the several species of rattlesnake, the water The centipede and the scorpion rank high moccasin, the copperhead, and the beautiful in the popular mind as poisoners, but they are coral snake, the little elaps of Florida, too small gentle apothecaries compared to the serpent. with us to be dangerous to man.

We are in America the privileged possessors India is preëminently the home of the poi- of the only other animal at all approaching sonous snakes, of which there are no fewer than the poisonous snakes in lethal vigor: it is a fifteen genera. The cobra is most abundant, lizard, the Gila monster (Heloderma suspectum) but the Ophiophagus elaps is the most dreaded, of Arizona. This strange creature is the only and attains at times the length of fourteen feet. poisonous lizard known. I have heard of but Unlike the cobra and the crotalus, this serpent one death in man from its bite, and for a long is viciously aggressive, and will pursue a man while it was looked upon by all except the with activity.

Indian as harmless. Sluggish, inert, well arAmong the vipers the daboya is entitled to mored with a tough, defensive skin, a feeder rank as a poisoner close to the cobra, and the on birds' eggs and on insects, it is most difficrotalidæ are represented by a number of cult to induce this good-humored and most snakes which are somewhat less effective slay- hideous reptile to bite at all. When once it ers than the cobra. While these genera are takes hold, no bulldog could be more tetoo sufficiently abundant on land, the In- nacious. The odor of its poisonous saliva is dian seas also abound in species belonging exactly like that of magnolia buds. Its bite to the family of hydrophidæ. These serpents causes no local injury, and its venom is a deadly are agile and dangerous, but as yet no one heart poison. seems to have made any examination of their All of the great family of thanatophidiæ venom, nor directly experimented to learn have substantially the same mechanical aranything of its relative hurtfulness. Poisonous rangements for injecting their venom. When water-snakes are found in abundance on the not in action the two hollow teeth known as shores of South America, and used to be fangs lie pointing backwards, wrapt in a loose

Vol. XXXVIII.- 66.

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cloak-like cover, a fold of the soft skin of the which is ordinarily employed to close the interior of the upper jaw. At the base of each mouth by lifting the lower jaw, to which it is of these fang teeth is an opening connected made fast. A little circular muscle around a with a tube running backwards under the eye part of the duct keeps it shut and prevents to an almond-shaped gland which forms the waste of venom. poison. This body continuously manufactures Let us observe what happens when the venom, and holds in its cavity a supply for rattlesnake means mischief. He throws himuse. Over the gland runs a strong muscle, self into a spiral, and about one-third of his

length, carrying the head, rises from the coil and stands upright. The attitude is fine and warlike, and artists who attempt to portray it always fail. He does not pursue, he waits. Little animals he scorns unless he is hungry, so that the mouse or the toad he leaves for days unnoticed in his cage. Larger or noisy creatures alarm him. Then his head and neck are thrown far back, his mouth is opened very wide, the fang held firmly erect, and with an abrupt swiftness, for which his ordinary motions prepare one but little, he strikes once and is back on guard again, vigilant and brave. The blow is a stab, and is given by throwing the head forward while the half-coils below it are straightened out to lengthen the neck and give power to the motions which drive the fangs into the opponent's flesh; as they enter, the temporal muscle closes the lower jaw on the part struck, and thus forces the sharp fang deeper in. It is a thrust aided by a bite. At this moment the poison duct is opened by the

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A SNAKE STAFF.

relaxation of the muscle which surrounds it, off a snake's head and then pinch its tail, the and the same muscle which shuts the jaw stump of the neck returns and with some acsqueezes the gland, and drives its venom curacy hits the hand of the experimenter through the duct and hollow fang into the if he has the nerve to hold on. Few men bitten part.

have. I have not. A little Irishman who took In so complicated a series of acts there is care of my laboratory astonished me by coolly often failure. The tooth strikes on tough skin sustaining this test. He did it by closing his and doubles back or fails to enter, or the ser- eyes and so shutting out for a moment the pent misjudges distance and falls short and too suggestive view of the returning stump. may squirt the venom four or five feet in the Snakes have always seemed to me averse to

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air, doing no harm. I had a curious experi- striking, and they have been on the whole ence of this kind in which a snake eight feet much maligned. six inches long threw a teaspoonful or more Any cool, quiet person moving slowly and of poison athwart my forehead. It missed my steadily may pick up and handle gently most eyes by an inch or two. I have had many venomous serpents. I fancy, however, that near escapes, but this was the grimmest of all. the vipers and the copperhead are uncertain An inch lower would have cost me my sight pets. Mr. Thomson, the snake keeper at the and probably my life.

Philadelphia Zoological, handles his serpents A snake will turn and strike from any post with impunity; but one day having dropped ure, but the coil is the attitude always assumed some little moccasins a few days old down his when possible. The coil acts as an anchor and sleeve while he carried their mamma in his enables the animal to shake its fangs loose from hand, one of the babies bit him and made an the wound. A snake can rarely strike beyond ugly wound. At present the snake staff is used half his length. If both fangs enter, the hurt is to handle snakes. doubly dangerous, because the dose of venom I saw one October, in Tangiers, what I had is doubled. At times a fang is left in the flesh, long desired to observe — a snake charmer. but this does not trouble the serpent's powers Most of his snakes were harmless; but he as a poisoner, since numberless teeth lie ready refused, with well-acted horror, to permit me to become firmly fixed in its place, and both to take hold of them. He had so two large fangs are never lost together. The nervous brown vipers; these he handled with care, but mechanism which controls the act of striking I saw at once that they were kept exhausted seems to be in the spinal cord, for if we cut of their venom by having been daily teased

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into biting on a bundle of rags tied to a stick. they give up, and seem to become indifferent They were too tired to be dangerous. I have to approaches, and even to rough handling. often seen snakes in this state. After three or four When a man or an animal is bitten by a rattlefruitless acts of instinctive use of their venom snake, death may take place in a few minutes.

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It has followed in man within a minute, but organ thus disordered. These phenomena unless the dose given be enormous, or by make the second stage of poisoning, and with chance enters a vein, this is very unlikely. The them there is, in finally fatal cases, a continuous bite is, however, popularly believed to be and increasing damage to the nerve centers that mortal, and therefore every case of recovery keep us alive by energizing the muscles which gives credit to some remedy, for it is a maxim move the chest walls and so give rise to the with physicians that the incurable and the filling and emptying of the lungs. easily relievable maladies are those which have When a physiologist speaks of a nerve cenmost remedies assigned to them.

ter he means by this a group of minute nerve Usually the animal struck gives a cry, and cells, and such a group he is apt to call a very soon becomes dull and languid. The ganglion, labeling it with the name of the disheart, at first enfeebled, soon recovers, the res- tant organ or the function to which it gives pirations become slower and weaker and more energy. Much alike in appearance, one ganweak, paralysis seizes the hind legs, the chest glion keeps the chest in motion, one influences becomes motionless, and at last death follows, the heart, one regulates the temperature of the usually without convulsions. Observe how body. When we throw into the circulation a little this tells us. Mere outward observation poison, it comes into contact with all of these gives us but slight explanatory help. If the numerous governing centers; but it does not animal should chance to survive over a half- trouble all of them alike. It has, as a rule, a hour, the part bitten swells, darkens, and fatal affection for one only, or far more for one within a few hours the whole limb may be than for another. Why venom should, as if by soaked to the bone with blood, which has choice, almost instantly enfeebie the ganglia somehow gotten out of the vessels and re- which keep us breathing, none can say. By and mained Auid in place of clotting. What is at by it also in turn disturbs other groups of nerve first local by and by becomes general, and cells, but its deadliest influence falls on the soon the blood everywhere ceases to have respiratory mechanism. The nerve cells thus power to coagulate. Then leakages of the attacked undergo no visible change; yet some vital fluid occur from the gums or into the mysterious alteration is present. Probably they walls of the heart, the lungs, brain, and intes- lose power to give out their waste products and lines, and give rise to a puzzling variety of to re-absorb from the blood the material needsymptoms, according to the nature of the .ful to sustain their local life and activity. At

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