CHAPTER XXVII

TORTOISES, TURTLES, AND LIZARDS

We now come to the cold-blooded animals, which are divided into three classes. First we have the reptiles, whose hearts are formed of three chambers, and which breathe air by means of lungs. Next come the amphibians, which are like the reptiles in many ways, but which have to pass through a tadpole stage before they reach the perfect form. And, thirdly, there are the fishes, whose hearts are divided into two chambers only, and which breathe water by means of gills.

TORTOISES AND TURTLES

At the head of the reptiles stand the tortoises and turtles, whose bodies are shut up in a kind of horny box, which we generally call the shell. In reality, however, it is not a shell at all; for the upper part, which we call the carapace, is a development of the spine and the ribs, while the lower part, which is known as the plastron, is a development of the breast-bone. These animals, in fact, have part of their skeletons inside their bodies and part outside; so that they are really shut up in their own bones!

The so-called shell of a tortoise or a turtle is always very hard and strong, so that you can stand upon quite a small tortoise without hurting it in the least and in most cases the head and legs can be tucked away inside it, so that the animal is safely protected from almost every foe.

None of the turtles and tortoises have any teeth. But the edges of their jaws are so sharp and horny that they can often inflict a very severe bite. Some of the larger turtles, indeed, could snap off the fingers of a man's hand as easily as you could bite through a carrot!

LAND-TORTOISES

The most famous of all the tortoises is the common land-tortoise, or Greek tortoise, which is found in many parts of the south of Europe, and also in Asia Minor. This is the animal which is so often kept as a pet, and about which so much pleasant literary interest has gathered. It does not grow to any great size, but will live in a garden for many years, crawling about by night as well as by day. Early in the autumn it buries itself underground, and falls into a deep sleep, from which it does not awake until the spring.

This tortoise is a vegetable-feeder, and is very fond of lettuce leaves, more especially when they are quite crisp and fresh, so that it can easily nip them to pieces with its sharp jaws. If they are rather old and stringy, it will hold them down with its front feet while it tears them asunder. And if you keep one of these animals as a pet, and want to give it a great treat, there is nothing that it likes better than a little milk. It is amusing to see how it drinks, for it first scoops up a little milk in its lower jaw, just as if it were using a spoon, and then holds up its head in order that the liquid may trickle down its throat.

There are a good many other kinds of land-tortoises, some of which grow to a very great size. The largest of all comes from the Galapagos Islands, and is quite a giant; for some of them are more than four feet long, and weigh between eight and nine hundred pounds! These huge creatures, however, are now nearly extinct.

TURTLES

The turtles are distinguished from the tortoises by the structure of their feet, which are flattened out in such a way as to serve as paddles in the water. For this reason these reptiles hardly ever come upon land except when they want to lay their eggs; and they can swim so well that they are often met with many hundreds of miles out at sea.

One of the best known of these creatures is the hawksbill turtle, which is so called because its mouth is shaped just like the beak of a hawk. The carapace is made up of thirteen large scales, which overlap one another for about a third of their length, just like the slates on the roof of a house.

These scales are very valuable, for the best tortoise-shell is obtained from them. When they are first taken from the animal they do not look like tortoise-shell at all, for they are dull and crumpled and brittle. But after they have been boiled, and steamed, and pressed for some hours they quite change their character, and become so soft that they can easily be molded into any required shape.

The eggs of this turtle are laid in a hole which the mother scrapes in the sand, and are hatched by the heat of the sun. As soon as the little turtles make their appearance they hurry off as fast as they can toward the water. But they are very good to eat, and a number of hungry animals and birds are always on the lookout for them, so that a very great many are snapped up and devoured before they can plunge into the waves.

The famous turtle soup, which is considered so great a dainty, is made from the flesh of the green turtle, which is found most plentifully off the island of Ascension and in the West Indies. It grows to a great size, for it is often four feet six inches in length and three feet in breadth, while it may weigh nearly three-quarters of a ton. Of course it is not at all easy to capture such big creatures. But they are generally pursued when they come on shore to lay their eggs, and are turned over on their backs by means of a lever. They are then perfectly helpless, and can be left lying where they are until a number of others have been overturned in the same way, when they are lifted into a boat one by one, and are taken on board ship. There they thrive quite well if a pail of water is thrown over them two or three times a day, and are generally in very good condition when they reach this country.

It is said that if one of these turtles has once begun to lay her eggs in the sand, nothing will induce her to pause in her task until she has finished it, and that even if the eggs are taken away from her as fast as she lays them, she will still go steadily on just as if she were undisturbed.

CROCODILES AND ALLIGATORS

Of course you know what these huge creatures are like. They are just enormous lizards, fifteen, or twenty, or even thirty feet long, with very short legs, and very clumsy bodies, and very long tails. And their great jaws are armed with rows of most terrible teeth.

But what is the difference between crocodiles and alligators? Well, in some ways they are certainly very much alike; but you can always tell them by the shape of their heads, for the muzzle of a crocodile is always narrowed just behind the nostrils, while that of an alligator is not. And in the crocodiles the fourth lower tooth fits into a notch in the edge of the upper jaw, so that you can distinctly see it even when the mouth is closed.

All these creatures live in the water, and spend a great deal of their time lying motionless on the surface, when they look like floating logs. One would think that they were fast asleep. But woe betide any animal which comes to drink from the bank close by, for one of the great reptiles instantly dives, swims swiftly along under water, and knocks it into the stream by a blow from its mighty tail.

There is scarcely any animal which does not fall a victim at times to these giant lizards. And as soon as the unfortunate creature is knocked into the water it is dragged beneath the surface, and held there until it is drowned. You would think that the reptiles themselves would be drowned, wouldn't you, as they have to remain submerged for many minutes with their jaws widely opened? But they have a very curious valve at the back of the throat, and as soon as the mouth is opened this closes so tightly that not even the tiniest drop of water can find its way down the throat.

Both crocodiles and alligators swim with very great speed by waving their powerful tails from side to side in the water. They can run, too, with some little pace upon land. But it is very easy to avoid them, for the bones of their necks are made in such a way that they cannot turn their heads, and all that one has to do if pursued is to spring suddenly to one side. But of course it is necessary to avoid the stroke of the tail.

The crocodiles always lay their eggs in the sand on the bank of a river. The eggs are about as big as those of a goose, and are generally buried at a depth of a couple of feet. The mother reptile always sleeps on the top of the nest, and it is said that when the little ones are ready to hatch out they utter a curious little cry. The mother hears this, and scoops away the sand under which they are buried, in order that they may have no difficulty in making their escape.

Crocodiles are found in the warmer parts of Africa, Asia, America, and Australia, and in some of the larger rivers are very plentiful. Just now and then they venture down into the sea. Alligators, which also are known as caymans and jacares, are only found in America and place their eggs in holes dug in the mud or earth beside the water. In the colder parts of the range they burrow under the mud of the banks and spend the winter in sleep.

THE LIZARDS

Lizards look at first glance like diminutive alligators, because most of them have long-jawed heads, short legs wide apart, and long tails; but really they are near relatives of the snakes, for not only their internal structure but the coat of scales is snake-like; but an important difference is that the jaws of the lizard are firmly hinged to a solid skull, while the bones of the skull of the snake, including those of the jaws, are connected by elastic cartilages which enable them to spread apart and permit the swallowing of a mouthful astonishingly large. But the lizards have no need of such a convenience, for they subsist almost wholly on insects, or else are vegetable-eaters. Lizards are almost entirely denizens of the tropics, and seem to rejoice in the fiercest heat. They will lie contentedly in the desert at noonday on rocks so hot that they would blister your hand if you touched them. Therefore few are to be found in Europe or North America, except in the extreme south.

THE BLINDWORM

Two or three small kinds are to be found in the south of England, one of which is curious as representing a tribe, largely represented in other parts of the world, of legless burrowing lizards, which look much like little snakes, for none of them are more than ten or twelve inches long, while they are of the thickness of a lead-pencil. They look so shiny and serpent-like that many people are afraid of them.

But the blindworm, or slowworm, as this creature is called, is perfectly harmless. It cannot bite you, for its teeth are far too tiny to pierce the skin; and it cannot sting you, because it has no sting. There is its odd little forked tongue, of course, which is always darting in and out of its mouth, just like that of a snake. But this tongue is only a feeler. Whenever a blindworm comes to an object it does not quite understand, it touches it gently all over with the tip of its tongue, just as we might touch it with the tips of our fingers.

Notwithstanding its name, the blindworm has a pair of very good, though rather small, beady black eyes; and, of course, it is not a worm.

During the daytime the blindworm mostly lies hidden under a large stone; and on turning such a stone over, one may sometimes find two or three of these lizards all coiled up together. But in the evening they leave their hiding-places, and go out to search for the tiny white slugs on which they feed.

When it is suddenly startled the blindworm sometimes behaves in a very odd way. It stiffens its body, gives a kind of shudder and a twist, and actually snaps off its own tail! Then the tail begins to writhe about on the ground, wriggling and curling and even leaping up into the air in the most curious manner; and while you are watching its antics, the blindworm creeps away into some place of safety. You would think that it must suffer a great deal of pain from this extraordinary injury, wouldn't you, and that the blindworm would feel it quite as much as a man would feel if his leg were cut off? But it does not seem to suffer at all; and stranger still, a new tail very soon begins to grow in the place of the old one, so that in the course of a very few weeks the lizard is just as perfect as it was before!

SKINKS

These are queer little lizards with four short legs and very stumpy tails, which are found in many parts of Africa and Asia. They live in sandy deserts, and are rather slow in their movements as a rule. But if a fly should settle anywhere near them they will dart upon it with the most surprising quickness, and will hardly ever fail to capture it. And if they are alarmed they will burrow into the sand so rapidly that they really seem to sink into it just as if it were water. In a very few seconds, indeed, they will bury themselves to a depth of at least two or three feet.

In olden days skinks were very much used in medicine, and the powder obtained from their dried bodies was thought to be a certain cure for many diseases! It does not seem a very nice idea, yet even to this day skinks are used for the same purpose in Eastern countries.

There are several different kinds of these curious lizards, of which the common skink, found in Northern Africa, is the best known. It is about three inches and a half in length, and is yellowish brown in color, with a number of darker bands on the sides of the body.

GECKOS

Odder still are the geckos, which have their toes swollen out at the tips into round sucker-like pads, by means of which they can climb a wall or a pane of glass with the greatest ease, or even walk about like flies on the ceiling. They are very fond of getting into houses, generally remaining hidden in some dark corner during the day, but coming out toward evening to search for insects, and continually uttering their curious little cry of "geck-geck-geck-o."

People used to be very much afraid of geckos, some thinking that they could squirt out poison from the pads of their toes which would act like the sting of a nettle, and others declaring that their teeth were so sharp and strong that they could pierce even a sheet of steel! But the real fact is that these lizards are perfectly harmless, and cannot injure any living creature except the insects upon which they feed. When they take up their quarters in a house they soon become extremely tame, and will even climb up on the dinner-table to be fed.

Geckos are found in almost all hot countries of the Old World, and nearly three hundred different kinds have been found altogether.

IGUANAS

American lizards are almost wholly members of the numerous iguana family, which takes its name from the big examples found from Mexico down into Brazil. The commonly known one when fully grown will measure four feet from the tip of its blunt, top-shaped head to the end of its long tapering tail. It looks rather forbidding, for a row of sharp spikes runs right along its back, while under its chin is a great dewlap. Yet it is not quite so terrible as it seems, for though it will bite fiercely if it is driven to bay, and use its long tail like the lash of a whip, it will always run away if it can, and will either climb into the topmost boughs of a tree, or plunge into a stream and swim away.

This reptile is a very good swimmer, driving itself rapidly through the water by waving its long tail from side to side, just like a crocodile or an alligator. And it can dive beneath the surface and remain at the bottom for a very long time without coming up to breathe.

Iguanas live chiefly among the branches of trees which overhang the water. Their flesh is very good to eat, for it is as tender as the breast of a young chicken. Their eggs, too, which they bury in the sand on the river-bank, are often used as food, and it is said that, no matter how long they may be boiled, they never become hard.

VARIOUS AMERICAN LIZARDS

The hot open plains which stretch from central Texas westward to the Pacific Ocean, and northward in Utah and Nevada, abound in a great variety of small lizards, none more than eighteen inches or so in length. Some are fat and short-tailed, some slender and swift, with tails like whiplashes. Some have gay colors and the power of changing them more or less, while others are dull of hue and uninteresting or repulsive to look at. Mostly they are insect-eaters, but some subsist upon plants; and one of the latter is the big fat one known in southern California as the "alderman."

Another strange one is the broad, flat creature so frequently seen all over the Southwest, and called horned toad, on account of its shape and habit of sitting on its squat legs, with its tail tucked sideways out of sight. It is covered almost all over with long and sharp spikes. Those on its head, which are directed backward, are the longest; and from these it gets its name of horned toad. But those on the back are very nearly as long, while there are several rows upon the tail as well. Yet it is perfectly harmless, for even when it is caught for the first time it never seems to use either its spikes or its teeth.

But it has another peculiarity which it sometimes uses as a means of defence, and that is a very strange one indeed. It actually squirts out little jets of blood from its eyes! That seems impossible, doesn't it? Yet there is no doubt at all about it, for when these lizards have been kept in captivity, and have been rather roughly handled, they have been known to squirt several drops of blood at a time to a distance of twelve or fifteen inches! Yet nobody seems to know how they do it.

THE GILA MONSTER

This same region, however, contains a poisonous lizard--the only kind of lizard in the world known to have sacs of venom in the mouth. This venom enters any wound made by the animal's biting with certain teeth, and acts upon the animal bitten like snake-poison. This is a sluggish, round-headed, short-tailed creature which dwells in the sandy plains along the Mexican boundary, and is called the Gila monster, or, scientifically, the _Heloderma_. Its scales are rounded, so that this lizard looks as if dressed in pebbled goatskin; and its colors are black and yellow, in irregular blotches. The hunters and sheep-herders are more afraid of it than need be, for it is sleepy and will never use its poisonous teeth without great provocation, so that it is only necessary to leave it alone in order to escape any harm.

THE FRILLED LIZARD

This lizard is a native of Australia, and has round its neck a kind of frill, or ruff, from six to eight inches in diameter! As a rule this frill is folded round the throat, so that from a little distance one would scarcely notice it. But as soon as the reptile is excited or alarmed it spreads it out, sits on its hinder legs and its tail, raises its head and body, and shows its teeth, just as if it were going to fly at its enemy. This is only pretence, however, for though the lizard grows to a length of nearly three feet, it is quite harmless.

Another very curious habit which this lizard has is that of walking upright on its hind legs, in the attitude of a dog when "begging." It will even run in this position, and most odd it then looks. It is a capital climber, and spends most of its life in the trees, to which it always tries to escape when it thinks itself in danger. In color the frilled lizard is yellowish brown mottled with black.

THE CHAMELEON

Strangest of all strange lizards, however, is the chameleon. In the first place, this lizard has a very long tongue, which it can dart out to a really wonderful distance from its mouth. This tongue looks very much like a worm, and is exceedingly sticky, so that all that a chameleon has to do when it sees a fly settling near it is to dart out its tongue and touch it with the tip. Then the fly adheres to it, and is carried back into the mouth so quickly that it is almost impossible to see what becomes of it. In this way it can catch a fly at a distance of fully six inches.

Then the chameleon has most extraordinary eyes. They are about as big as peas; but instead of having lids which move up and down, as ours do, they are entirely covered by the lids with the exception of just a tiny round space in the middle. The lizard sees, in fact, through a hole in the middle of its eyelid. That is strange enough; but what is stranger still is that the animal can move its eyes in different directions at the same time. They are hardly ever still for a single moment. But instead of moving together, like those of all other animals, one may be looking upward toward the sky and the other downward toward the ground; or the right eye may be peering forward in front of the nose while the left one is glancing backward toward the tail! Indeed, it would be very difficult to find an odder sight than that of a chameleon when it is moving its eyes about. They really look just as if they belonged to two different animals.

But the most wonderful fact of all about the chameleon is that it can change its color whenever it chooses.

How it does so no one quite knows. But the very same animal which is brown all over as it sits upon a branch will become green all over if you put it among leaves. The last thing at night, probably, you will find that it is gray. Next day, perhaps, brown spots will appear upon its body, and pinkish stripes upon its sides. And occasionally it may be violet, and sometimes yellow, and sometimes nearly black. So that if you were to go and look at a chameleon, and then go and look at it again half an hour afterward, you might very likely take it for a wholly different animal!

Then the chameleon has very odd habits. If it is annoyed, for example, it puffs out its body in the most extraordinary way till it is nearly double its ordinary size and its skin is stretched almost as tight as the parchment of a drum. When it is caught it hisses like a snake. And really it must be the very laziest creature on earth. If it lifts a foot into the air it will often wait for quite a minute before it puts it down again, and for two or even three minutes more before it takes a second step. Then it always has to rest for some little time after uncoiling its tail from a branch, while when it coils it round another it stops and rests again. It will hardly travel two yards, in fact, in a day.

Chameleons are found in many parts of Africa and Asia, and also in Southeastern Europe.