Guillemots

Very common are guillemots on some coasts where there are sea-fronting cliffs, and freedom from disturbance. Thus they abound along the shores of Labrador and Greenland, and many varieties are to be found along the northern coasts of Alaska, and about the borders of the Arctic sea, often thronging in great numbers together with puffins, kittiwakes, petrels, and gannets, each kind occupying separate parts of the cliffs and living on friendly terms with their neighbors.

Guillemots feed entirely upon fishes, which they chase under water, using both their wings and feet, just as dabchicks do. They do not make any nest, but lay a single egg on a bare ledge of rock which is often only a very few inches wide. One would think that this egg would be in great danger of being knocked over the edge. But it is very large at one end and very much pointed at the other, so that if it is struck it only rolls round and round. In color it is green or blue, blotched and streaked with black.

The Albatross

One of the largest of all the sea-birds is the albatross, which is found chiefly in the tropical seas. When the wings are fully spread, they sometimes measure nearly twelve feet from tip to tip. Yet the entire weight of the bird is not more than sixteen or seventeen pounds. It often remains at sea for weeks or months together, sometimes remaining in the air all through the night as well as all through the day, and following ships for hundreds of miles in order to feed upon the refuse which is thrown overboard. Its appetite is enormous, for it has been known to gulp down a great piece of whale's blubber, weighing between three and four pounds, and then to return almost immediately for more!

Great numbers of albatrosses nest together on uninhabited islands, each pair scooping together a quantity of clay, grass, and sedge, which they arrange in a conical heap about ten or twelve inches high, with a little hollow at the top. Only a single egg is laid, which is quite white, and is rather larger than that of a goose.

The Puffin and the Penguin

Two most curious birds must be mentioned in conclusion. The first of these is the puffin, which is found plentifully in one or another species on all northern coasts where there are bold cliffs. An odder and more quaint-looking bird it would be difficult to imagine, for it has a beak quite large enough for a bird six times its size, while that beak, which is banded with bright crimson, gray, and brilliant yellow, looks just as if it had been stuck on with glue! More than that, it does not appear to fit very well; so that altogether, with its short, squat body and stout little legs, the puffin is by no means a graceful bird. It is often known as the sea-parrot.

On dry land, the puffin is very awkward, and can only waddle along slowly and clumsily. But it is a good swimmer and diver, and can chase and overtake small fishes with the greatest of ease. It is also able to fly very well, and takes long journeys over the sea when it comes to us in the spring, and again when it goes southward in the autumn. It makes no nest, but finds a cranny, digs out a hole in the face of a cliff to the depth of about three feet, and lays a single grayish-white egg at the end of the hole.

Odder still is the penguin, whose wings are but little more than flippers, with scales on their upper edges instead of feathers! It cannot fly, of course; but it uses its wings for two purposes. For if it is frightened upon land it throws itself down on its breast and scuttles along on all fours, just as though its wings were legs, and if it wants to chase a fish in the sea it swims with them, just as though they were paddles.

There are a good many different kinds of penguins, all of which are found in the southern hemisphere. On some of the islands in the Pacific and Antarctic oceans they are found in immense numbers, and have a curious way of standing side by side upon the shore in long rows, with their flippers hanging down on either side of their bodies. From a distance, indeed, they might almost be mistaken for lines of soldiers standing at attention. When the breeding-season begins they become very busy, picking up stones, carrying them about with a great deal of fuss, and then carefully arranging them in position, every now and then turning their beaks up to the sky, waving their flippers, and making a curious gobbling noise. If a sitting hen leaves her nest for a little, all the other hens become greatly excited, and peck at her as she passes by in order to drive her back again, croaking loudly in chorus, and evidently feeling extremely indignant with her for neglecting her duties.

When these odd birds are sitting on a ledge of ice, and want to get down into the sea, they often throw themselves upon their breasts, and "toboggan" down the slope into the water!

REPTILES

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.

CHAPTER XXVIII
SNAKES

There are a great many different kinds of snakes; but before we read about some of them, we must tell you some thing about the wonderful way in which their bodies are made.

In the first place, then, remember that snakes have a very large number of those sections or pieces forming the spine which we call vertebræ. We ourselves have only thirty-three of these little parts when we begin life, and twenty-six afterward; this difference in number being caused by the fact that five of the joints very soon unite into a bony mass at the lower end, which we call sacrum, while four more unite into another, which we call the coccyx. But some snakes have hundreds of these vertebræ. The boas, for example, have no less than three hundred and four!

In the next place, remember that all these vertebræ are fastened together by what we call ball-and-socket joints. That is, there is a round knob at the back of each vertebra which fits into a socket in front of the vertebra behind it. This gives to the spine of a snake great strength, for a vertebra cannot be forced out of its place without breaking the vertebra behind it. And it also allows the spine to be curled and twisted about in almost any direction; so that a snake can easily coil up its body like a spring, or even tie it into a knot.

Then, remember that a snake has a great many ribs. We have twelve pairs of these important bones, most of which are jointed to the breast-bone in front. But a snake may have as many as two hundred and fifty-two pairs of ribs, while it has no breast-bone at all; so that the tips of all the ribs are free. And every rib is fastened to a vertebra of the spine by a ball-and-socket joint, just like those which fasten the vertebræ themselves together. Besides this, there are no less than five separate sets of muscles connected with the ribs, so that the snake can move those bones about quite easily.

It is really by means of its ribs that a snake is able to glide over the ground. If you were to look at the under side of a snake's body, you would see that the scales are quite different from those on the upper part. On the back and sides the scales are quite small, and are almost oval, or oblong; but on the abdomen they are very long and very narrow, and are set crosswise like the laths of a Venetian blind.

Now the tips of every pair of ribs in a snake's body are fastened to one of these long abdominal scales in such a manner that when the snake moves the ribs forward the edge of the scale is raised—very much as you can raise the laths of the Venetian blind by pulling the cord at the side; and the snake travels by moving forward its ribs in turn, and catching hold of the ground with the edges of the scales, using first the ribs of one side and then of the other.

When a snake is crawling, however, it does not curve its body into upright loops as inaccurate pictures sometimes represent, but keeps it pressed flat upon the ground, so that the scales may be able easily to take hold of any little roughness upon the surface. And when it climbs a tree it does not twine its body round and round the trunk, but crawls straight up it, just as it crawls along the ground.

The mouth of a snake is very curiously made. We are not speaking now of the fangs of the poisonous serpents; we will tell you about these by and by. But remember that the mouth must be made in a very strange way, in order to allow these creatures to swallow their victims, which are often a good deal larger round than their own throats.

It sounds impossible, yet the snake can swallow an animal larger in diameter than its own throat, because the bones of its jaws, instead of being firmly fastened together as ours are, can be forced a long way apart, so as to make room for the carcass to pass.

Besides this, it has no less than six separate jaw-bones, four in the upper part of the mouth and two in the lower, every one of which is set with sharp, hooked teeth; and the points of these teeth are directed toward the throat. Now every one of these jaw-bones can be moved backward and forward at will. So when a snake wishes to swallow the body of a victim, it first of all seizes it in its mouth, and then pushes one of the jaw-bones forward and takes a firm hold with the teeth. Then it pushes another forward, and then a third, and then a fourth; and so it goes on, each time taking a fresh hold with the hooked teeth, till at last the carcass is forced into the mouth. Then the bones separate, so as to make plenty of room for it to pass, and the alternate action of the jaws goes on as before till the carcass is forced into the throat. And then the flesh of the throat, which is very elastic, stretches out too, till before very long the carcass disappears altogether.

Then the eyes of snakes are made in a very curious way, for the eyelids, which are quite transparent, do not open and shut as ours do, but cover the eyes altogether. So a snake cannot blink; and it looks at you through its own eyelids, which are very much like little spectacle-glasses fastened into the skin!

When a snake throws off its skin, which it always does once in a year, and sometimes oftener, the eyelids are thrown off with it, and a pair of new ones are found lying below all ready to take their place. Just while this is happening (and it may take a day or two) the creature is trying to look through a double layer of eye-coverings, and can see very poorly until the outer one slips off. This is the explanation of the popular saying that snakes are blind in August (the usual skin-changing time).

Harmless Snakes

All serpents may properly enough be divided into two sections—the non-poisonous ones, which are "harmless," so far as their bite is concerned; and the poisonous ones, which inject a more or less deadly venom into wounds made by certain long weapon-teeth called fangs.

Let us consider first, for a moment, the harmless ones. The great majority of them—of the common snakes of the whole world—belong to a single family called colubers; and this family far outnumbers all other serpents. Most of its members are of small size; few exceed two yards in length, one of the exceptions being our handsome king-snake of Texas and westward, which is a variety of the northern milk-snake. All are slender, agile, sometimes remarkably swift, with small heads, tapering and unarmed tails, and little or no means of defence, although some of them make such a show of fighting that they terrify many an enemy into leaving them alone.

To this great family belong our various blacksnakes, or blue racers, which occasionally are more than six feet long, and are among the worst robbers of birds' nests, eating both eggs and young, and the mother bird as well if it is small, and is not quick enough in seeking to escape. This is the snake about which stories of so-called fascination are told; we do not think there is much truth in them, but that the bird is simply reckless in her efforts to drive away the robber, and flies too near its darting jaws. The blacksnakes are exceedingly swift runners and agile climbers. Another excellent climber is the slender greensnake, which is so near the color of the leaves that it will not be noticed easily as it hangs in loops upon the branches of a bush, waiting quietly for some insect to come within reach. Most of our snakes, however, spend their time mainly on the ground, searching about the grass, among the tussocks of a swamp, or amid dense thickets, after frogs, toads, tadpoles, ground-nesting birds, mice, and especially insects, which last form the principal food of the smaller kinds. Among these probably the most often seen are the striped garter-snakes which abound in meadows and about haystacks and old barns, where they search holes and corners for mice and beetles. The warm, soft soil of old barnyards is a favorite place for the laying of their eggs by snakes, most of which bury them in such places and leave them to be hatched by the warmth of the sunshine. Nearly every pond, marsh, and slow stream abounds also in water-snakes, which are ugly in disposition as well as in color, and feed mainly on fishes, both dead and alive. Of this kind is the only snake to be found in England except the viper.

Perhaps the most curious of the colubrine snakes is the egg-eating snake of South Africa. It is quite a small snake, not more than two feet long, and scarcely thicker in body than a man's little finger; yet it will swallow pigeons' eggs quite easily, and, if it is very hungry indeed, will dispose of a hen's egg! This, of course, is owing to the way in which the bones of the mouth are made. But if you were to watch one of these snakes as it was eating an egg, you would see a very strange thing happen. The egg would pass down the throat, and for a few inches you would be able to watch its outline as it moved along toward the stomach. Then, quite suddenly, the swelling would disappear! The fact is this. About thirty of the vertebræ have each a long, slender spine springing from the lower surface, and the tips of these spines pass through the upper part of the throat and project inside it, just like a row of little teeth in the wrong place. Just as the egg, while it is being swallowed, comes against these teeth, the snake contracts the muscles of its throat. The result is that the teeth pierce the egg from end to end and cut it in two. Then the contents flow onward down the throat, while the two halves of the shell, nearly always packed one inside the other, are shortly afterward spit out of the mouth.

Pythons

The pythons are very formidable snakes, not because they are venomous—for they have no poison-fangs—but owing to their immense size and strength. When fully grown they may measure as much as thirty feet in length, while their bodies are as big round as a man's thigh; and even when they are only half as long they are still most dangerous creatures, for they could crush a man to death in two or three minutes.

When a python attacks, it seizes its victim with its jaws, flings its coils one over another around it, and then squeezes so hard that in a very few minutes the bones fly into splinters, and the body is reduced to pulp. And a large python can swallow a half-grown sheep or a good-sized dog without any difficulty at all.

After the snake has swallowed its victim it becomes very drowsy, and often sleeps heavily for several days.

Another very curious fact with regard to the python is that it actually hatches its eggs by the warmth of its own body. It first collects the eggs into a little pile, and then coils itself round them, after which it remains perfectly still for nearly two months. During the whole of that time its bodily heat is much greater than usual, and at last the egg-shells split, and out from each comes a baby python. A fortnight or so later they change their skins, and then are quite large and strong enough to kill and swallow small birds.

Pythons inhabit nearly all the hotter parts of Africa, Asia, and Australia, and are sometimes known as rock-snakes, on account of their living much in rocky places.

Boas

The boas, one kind of which, the boa-constrictor, has long been famous among monsters, are much like the pythons, but are found only in tropical America and in Madagascar, and spend the greater part of their lives in the trees. They are quite as large as the pythons, and quite as formidable. It is said, indeed, that the anaconda, which is the largest of all, sometimes reaches a length of forty feet; and there is a stuffed skin, twenty-nine feet long, in the Natural History Museum at South Kensington, London. One can easily imagine what a terrible enemy such a snake as this would be, and how helpless even a strong man would find himself when wrapped in its mighty coils!

The anaconda is very fond of lying in the water with only just its head raised above the surface, and there waiting for some animal to swim within reach. But most of the boas lie in wait for their prey on one of the lower branches of a tree, in readiness to strike at any small creature that may pass beneath.

Some years ago a most singular accident happened in the reptile house at the London Zoo. Two boas, one eleven feet long and the other nine feet, were living in the same cage, and always seemed on the very best of terms. One night a couple of pigeons—one for each snake—were put into the cage, and the house was shut up as usual. Next morning, however, when the keeper opened it, the smaller snake had disappeared, and there was no hole in the cage through which it could possibly have escaped. At first the keeper was puzzled; but soon he noticed that the larger serpent was not coiled up as usual, but was lying stretched out straight upon the ground. Then he understood what had happened. The big snake had swallowed the smaller one during the night, although it was only two feet shorter than itself!

Most likely both snakes had seized the same pigeon at the same moment. Before very long, of course, their jaws would have met in the middle. Now when one of these big snakes has once seized its victim it cannot let go, because of the way in which its jaws and teeth are made, but must go on trying to swallow it. So, you see, when the jaws of the two snakes met in the middle of the pigeon neither could give the bird up to the other, because neither could withdraw its teeth, and the larger one, in fact, could not help swallowing the smaller! And since that time two or three other accidents of the same character have been prevented only by the constant watchfulness of the keeper.

Poisonous Snakes

In all these reptiles the poison-fangs are two in number, and are situated in the upper jaw. They are very sharp indeed, and are almost as brittle as glass. So while they are not in use they are folded back out of harm's way upon the roof of the mouth. But if by chance they should be broken, there are three or four other pairs lying ready for use behind them which will quickly grow forward to take their place.

Generally there is a tiny hole just under the tip of the fang, which opens into a narrow passage running right through the center. But in some snakes there is only a groove outside the fang. In either case, however, the muscles which surround the poison-bag are arranged in such a way that as soon as the snake strikes its victim a drop of poison is squirted down each of the fangs, and so into the wound.

Vipers

The only poisonous snake found in Europe is the viper, or adder. It is not by any means a large snake, for it is seldom more than twelve or fourteen inches long. It has a zigzag chain of black, lozenge-shaped markings all the way along its back.

Vipers are generally found on heathy commons and moors, and are very fond of lying on a patch of bare, sandy ground, and enjoying the warmth of the sun. They never attempt to bite unless they are interfered with, but always try to crawl away, if alarmed, into a place of safety. Their poison is not strong enough to kill a man, unless he happens to be in a very bad state of health at the time when he is bitten; but it would be quite sufficient to cause the bitten limb to swell up to double its size, and to lead to a great deal of suffering and sickness.

Cobras

Far more deadly is the bite of the cobra, which is found plentifully in India. Any one who is bitten by this formidable snake is almost sure to die within two or three hours.

The upper part of a cobra's neck is widened out into what is called the hood, which can be spread out or folded up at will by the action of the ribs. On the upper part of this hood is a dark mark, which looks almost exactly like a pair of spectacles. When a cobra is about to strike it always raises its head and neck and spreads this hood before darting at its foe.

In many parts of India cobras are caught and tamed by men who are called snake-charmers, and who sometimes capture them by playing an odd tune upon a sort of wooden pipe. This music seems to fascinate the snake, which comes out of its hole, rears up its head and neck, and begins to sway slowly from side to side. Then, still playing, the charmer moves his right hand very slowly indeed until it is just behind the snake's head, when he suddenly grasps the reptile round the neck. It is now, of course, quite helpless, and is quickly transferred to his bag.

Many charmers carry cobras about with them, which they handle quite freely. But in these cases the poison fangs have been carefully extracted, so as to render the reptiles harmless.

Cobras are very fond of eggs, and if they can find a rat-hole which opens into a hen-house they will often take advantage of it in order to rob the nests. But sometimes, when they have swallowed several eggs, and the hole happens to be a small one, they cannot crawl out again, and are found and killed when the house is opened in the morning.

The Puff-Adder

Quite as deadly is the puff-adder, of Africa, which has a way of lying almost buried in the sand, so that it is not easily seen; and if it is disturbed it does not crawl away, as most poisonous snakes will do, but remains quite still, merely drawing back its head in order to strike. When fully grown it is about six feet long, and its poison is so deadly that even a horse has been known to die within two or three hours of being bitten.

This snake is called the puff-adder because it draws in a very deep breath when it is annoyed or irritated, and puffs out its whole body to nearly double its proper size. It then allows the air to escape gradually, with a kind of sighing noise, draws in another deep breath, and so on over and over again.

Pit-Vipers

Australia, also, has some snakes whose bite is very deadly; and in general the tropics abound in these dangerous reptiles. This is as true of America as elsewhere, but all the American venomous serpents are of a kind peculiar to this continent, called pit-vipers. Some of them have rattles at the end of the tail and some lack this appendage, but all are much alike. Certain of the most dreaded, such as the fer-de-lance and the bushmaster, belong to the West Indies and Northern South America; but really the worst of the whole bad lot, because of its great size and sullen ferocity, is the huge diamondback rattlesnake of the Southern States. It is in some cases longer and heavier than any other known venomous snake; and its bite, if the wound is well poisoned, means almost immediate paralysis and death.

Rattlesnakes

Several different species of rattlesnakes are scattered over the United States, and in some places, as on the hot dry plains of the Southwest, and in the arid mountains of Utah and California, are numerous enough to be troublesome. The cutting away of forests, draining of swamps, and cultivation of prairies, soon destroy these pests in thickly settled regions; but where rocky hills occur they linger for a long time, because the breaks and little caves among the ledges offer them secure retreats, winter homes where they sleep in safety, and proper nurseries for the young, which are not produced from eggs, as in the coluber family, but are born alive.

The rattles from which these serpents take their name, are a number of hollow, horny, button-like structures at the tip of the tail, which rattle together, with a peculiar humming sound, when the creature shakes its tail, as it is sure to do when disturbed or angry. It thus gives a warning to the man who might not have noticed the sluggish creature in his path in time to jump aside. Not all of the tribe have a rattle, however; and one of the reasons why our water-moccasin and copperhead are so much dreaded is that they possess no rattle, and therefore sound no "keep-off" warning.

All our American venomous snakes are too heavy and slow to climb trees. They get their prey—mice, gophers, snakes, etc.—by going to a place where it is likely to be running about, and then patiently waiting until something comes within striking distance.

CHAPTER XXIX
AMPHIBIANS

You will remember that the amphibians are distinguished from the true reptiles by having to pass through a tadpole stage before they obtain their perfect form. A good example is the frog, which in one kind or another exists in all parts of the earth except the very coldest. No doubt, you have often seen great masses of its jelly-like spawn floating on the surface of ponds early in the spring; and you must have wondered how such small creatures as frogs could possibly lay such enormous batches of eggs.

But the fact is that when these eggs are first laid they are very tiny. Each egg is only about as big as a small pin's head. Instead of having shells, however, they are covered with a very elastic skin, while at the same time they soak up water. So, as soon as they pass into the pond they begin to swell, and very soon each egg is as big as a good-sized pea.

Tadpole and Frog

In the middle of each egg is a round black spot, which increases in size every day. This is the future tadpole, and after a time the egg-skin splits, and out it tumbles into the water.

It is an odd-looking creature—just a big round head with a tiny pair of gills and a little wavy tail, and nothing else at all. But it manages to swim by wagging its tail, and it feeds on the tiny scraps of decaying matter which are always floating about in the water of the pond. Before long a little pair of legs begin to show themselves just at the base of the tail. A few days later another pair begin to grow in front of them. Then, by slow degrees, the tail passes back into the substance of the body, and so do the gills, while lungs are developed and nostrils are opened. And by the time that all these changes have taken place the tadpole has ceased to be a tadpole and has turned into a frog.

It leaves the water now and lives upon land, feeding upon small insects, which it catches in a most curious way. Its tongue is turned, as it were, the wrong way round; for the root is just inside the lips, while the tip is down the throat. Besides this, the tongue is very elastic and very sticky. So the animal catches its victims just as the chameleon does, flicking out its tongue at them and just touching them with the tip, to which they adhere. And as the tongue is drawn back into the mouth it pokes them down the throat; so that frogs do not even have to take the trouble of swallowing their dinner.

If you look at a frog's hind feet, you will notice that the toes are joined together by webbing. This allows them to be used in the water as well as upon dry land. It is generally said that frogs swim. But if you watch them in the water you will see at once that they do not really swim at all, but leap along, just as they leap along the ground. And each leap carries them through the water for some little distance.

Toads

In some ways toads are like frogs; but you can tell them at once by their rough, dry skins, which are covered with warts like glands. And they crawl over the ground, instead of leaping as frogs do. They are very common almost everywhere, and you may often find them hiding under logs or large stones during the daytime.

Toads do not lay their eggs in great masses, as frogs do, but arrange them in strings about four feet long and an eighth of an inch wide. Each of these strings consists of two rows of eggs fastened side by side together. The tadpoles are very much like those of the frog, the chief difference being that they are rather smaller and blacker.

Newts

All through their lives newts keep their tails, instead of losing them when they cease to be tadpoles.

You can find newts in plenty all through spring and summer by fishing with a small net in any weedy pond; but you will find that they are not all alike. Some have wavy crests running all along their backs; others have none; and some are brightly colored while others are plain olive green all over. Often in the woods in certain parts of the United States you will meet with little newts traveling about on the damp old leaves; and they are very conspicuous because of their brilliant vermilion color. These are young green newts which come out of the water, live ashore for a year or so in the red suit, and then go back to the water and a green coat.

Newts lay their eggs in a very curious manner. They do not fasten them together in great batches, like the frog, or in long, narrow strings, like the toad. They lay them one by one. And the mother newt takes each egg as she lays it, places it in the middle of the narrow leaf of some water-plant, and then twists the leaf neatly round it with her little fore feet, so as to wrap it up in a kind of parcel! The tadpole which hatches out of this egg is very much like that of a toad or a frog; but the front legs are the first to appear, instead of the hind legs, while the tail, of course, does not pass back into the substance of the body.

Newts swim with their tails, and very pretty and graceful they look as they move through the water. When they cease to be tadpoles, of course, they breathe air, just as toads and frogs do, and have to come up to the surface every two or three minutes to obtain it. And as long as they live in the pond they feed upon grubs and worms and tiny water-insects.

Salamanders

The curious creatures known as salamanders are related to the newts, and begin their lives in just the same way. But after they have ceased to be tadpoles they only visit the water for two or three weeks in the spring.

The most celebrated member of this group is the spotted salamander, which is found in Central and Southern Europe, and also in Algeria and Syria. When fully grown it is about eight inches long, and may be known at once by the two rows of large yellow blotches which run down from the back of its head, right along its body, to the very tip of its tail.

In days of old it was thought that the salamander had the power of walking through fire without being burnt! And it was also supposed, if it were attacked, to spring upon its enemy, bite out a piece of his flesh, and then spit fire into the wound! As a matter of fact it is almost harmless, and may be picked up and handled without the slightest danger. But the glands on its skin, like those on the toad's head and back, contain a rather poisonous fluid, which is squirted out if they are squeezed. So that if a dog were to pick up a salamander he would be quite sure to drop it again very quickly, and would most likely foam at the mouth for some little time.

Salamanders are very slow and timid creatures, and generally spend the whole of the day concealed in some crevice, or in the hollow trunk of a tree, or perhaps under a large stone. They feed upon slugs and small insects.

There are several kinds in North America, some of which, as the hellbender, are a foot or more in length.

The giant salamander, which is sometimes nearly a yard long, is found in the rivers of China and Japan, and spends the whole of its life in the water. It feeds chiefly upon fishes.

The Axolotl

This is one of the most singular of all the amphibians. It is found in North America. Sometimes it develops into its perfect form, and sometimes it remains a tadpole all its life, and yet lays eggs just as though it were adult!

In the lakes of the southern Rocky Mountains the life of this creature is just like that of any other batrachian. That is, it is hatched out of the egg as a tadpole, grows first one pair of legs and then another, loses its gills by degrees, and at last appears in a lizard-like form, leaving the water and living upon dry land. But in the lake which surrounds the city of Mexico it never becomes anything more than a big tadpole, keeps its gills throughout its life, and does not leave the water at all.

The Olm

The olm, or proteus, is found only in the underground lakes of Carniola and one or two other parts of Central Europe. It is about a foot long when fully grown, and has a slender, snake-like body, with a pair of tiny legs just behind the head, and another pair at the base of the tail. It is perfectly blind, the eyes being hidden under the skin, and yet cannot bear light. For if it is kept in captivity it will always hide in the darkest corner that it can find. And it has been known to live in confinement for five years without once taking any food.

What the habits of this extraordinary animal are in nature no one knows, as it has never been found except in these underground lakes.

In color the olm is pinkish gray, with bright-red gills, and there are from twenty-four to twenty-seven grooves upon either side of its body.

FISHES

CHAPTER XXX
FRESH-WATER FISHES

The lowest class of the vertebrate animals consists of the fishes. These are easily distinguished. Some of the reptiles, it is true, are very fish-like. But then they have three chambers in their hearts, while the true fishes only have two. Then fishes never have limbs, the place of which is taken by fins; and further, they breathe water by means of gills. There are other differences as well; but these are quite sufficient to show us that reptiles and fishes cannot possibly be mistaken for one another.

Between the two, however, come several very curious creatures, which seem to be partly reptiles and partly fishes; for they have four slender members which hardly seem to be legs, though they cannot possibly be described as fins, while they possess not only gills but lungs as well.

The Mud-Fish

One of these is the odd mud-fish of the African rivers. In general appearance this animal looks something like an eel, and it grows to a length of about three feet. Its four long ray-like limbs seem to be quite useless to it, and it swims by means of its tail, along the upper part of which runs a narrow fin. It is a creature of prey, feeding upon other fishes, and when food is plentiful, it just takes one bite out of the lower part of their bodies and no more.

In summer the rivers in which it lives often dry up altogether, and the mud at the bottom is baked as hard as a brick by the rays of the sun. So, as soon as the water begins to get shallow, the animal burrows deep down into the mud, curls itself up like a fried whiting, and falls fast asleep for several months, just as hedgehogs and dormice do during the winter in cold countries. Then, when the rainy season comes and the rivers fill up again, it comes out from its retreat and swims about as before. It is from this habit that it gets its name of mud-fish.

Now we come to the true fishes; and perhaps our best plan will be to read about some of the fresh-water fishes first, and afterward about some of those which live in the sea.

Sticklebacks

Let us begin with a little fish which is very common in almost every pond, but is nevertheless very curious and very interesting. When fully grown, the stickleback is about three inches long, and you can tell it at once by the sharp spines on its back, which it can raise and lower at will. It uses these spines in fighting. For the male sticklebacks, at any rate, are most quarrelsome little creatures, and for several weeks during the early part of the summer they are constantly engaged in battle.

At this season of the year they are really beautiful little fishes, for the upper parts of their bodies are bright blue and the lower part rich crimson, while their heads become pale drab, and their eyes bright green! And apparently they are very jealous of one another, for two male sticklebacks in their summer dress never seem able to meet without fighting. Raising their spines, they dash at one another over and over again with the utmost fury, each doing his best to swim underneath the other and cut his body open. When one of them is beaten he evidently feels quite ashamed of himself, for he goes and hides in some dark corner where nobody can see him. And, strange to say, as soon as he loses the battle his beautiful colors begin to fade, and in a very few hours they disappear altogether.

About the beginning of June, all the male sticklebacks which have not been beaten set to work to build nests. These nests are shaped like little tubs with no tops or bottoms, and they are made of tiny scraps of grass and cut reed and dead leaf, neatly woven together. As soon as they are finished the female sticklebacks lay their eggs in them. Then the males get inside, and watch over the eggs until they hatch.