Chapter II: Part 2

“I think we had better take our newts back to the pond now, Frank.”

“Oh, do let us keep them for a day or two longer, Uncle George. They are getting quite tame.”

As he spoke, Frank drew his finger slowly round the outside of the glass vessel that held the newts. One of the creatures swam round, following his finger.

“Look, Uncle George! He knows me.”

“He is hungry, and thinks you ought to have a small worm in your fingers.”

“_Thinks?_ Uncle George. Can newts _think_?”

“It looks as if they could, does it not? We feed these creatures every day, and they have got into the habit of looking for food every time we come near them. But here comes Tom with the worms.”

It was curious to watch how the newt acted when a tiny worm was given it. At first it seemed not to see the worm, although it was wriggling at his nose. It crept back slowly about two or three inches, then all at once it sprang upon the worm and gobbled it up.

“You must tell us all about the newt, Uncle George,” said Tom.

“I should like to know how much you two boys have found out by feeding and watching these two,” said Uncle George. “So just tell me what _you_ know about the newt first, then perhaps I can tell you some things about newts, frogs, and toads which you do not know.”

“Well,” began Tom, “the newt lives in water. He has four feet, with pretty little toes upon them, and a long tail. He feeds upon worms, tadpoles, and other small animals, and he swallows them whole, because he has no teeth.

“The male has a huge crest, and is gay with bright colours.

“The female has no crest. She lays her eggs upon the pond weeds. A single egg is laid upon a leaf. The leaf is then rolled round it, so as to hide it from enemies.”

“Very good, Tom,” said his uncle; “but you have not told us about the newt’s skin.”

“Oh, I forgot that,” Tom went on. “The newt has a lovely silky skin, which it only wears for about a week, then it casts it off. Now, tell us something more about them, Uncle George.”

“The newt does not live in the water all the year,” said Uncle George. “During autumn and winter great families of newts sleep together under stones and in dry holes in the earth. They only go to the pond in early spring to lay their eggs.”

“Do newts ever become frogs or toads?” asked Frank.

“Oh no, Frank, never. I know what makes you think that. It is because the young frog, just before he loses his tail, is very like a little newt.

“Young newts are tadpoles too, but they differ very much from frog tadpoles. Newt tadpoles live in the pond for more than a year. They have feathery outside gills on all that time. Their _fore_ feet are formed first. If you remember, our frog tadpoles got their hind legs first.

“Long ago people believed all sorts of absurd things about the poor, harmless newt. They were afraid to touch it. Every newt found was killed at once, for it was thought to have a sting and poison bag. Even at the present day many people believe that newts and toads are dangerous animals.”

“How can you tell a toad from a frog, Uncle George,” Tom asked.

“They are very different from each other, both in shape and in their ways of living. The toad is a fat, clumsy animal. His skin is dull and warty. He does not hop, but crawls or walks lazily along.

“He lives upon flying insects, which he catches with his curious long tongue. He gets very fat during summer and autumn.

“Before winter comes on, he looks out a snug hole under a root or stone. Here he sleeps the whole winter through.

“In spring he wakes up, lean and hungry, and betakes himself to the pond.

“The eggs of the toad are laid in the water in long strings, each like a double row of beads. They hang gracefully upon the water weeds, and look very pretty.

“The toad tadpoles are very like those of the frog. They go through the same changes.

“The toad also casts his skin, but he does not throw it away like the newt. He takes his old, cast-off skin, rolls it up into a neat little ball, and _swallows it_.

“The frog’s body is more slender. His skin is slippery. It is not dull and dingy like that of the toad. It is of a bright greenish yellow colour, marked with black spots of different sizes.

“The frog can change his colour from light to dark. He has long hind legs which enable him to hop very high on land and to swim very fast in the pool.

“He likes the long, damp grass, where he catches flies, beetles, and slugs.

“He sleeps through the winter, buried in the mud at the bottom of the still pool.

“Like the toad, the frog catches his prey by means of a long, sticky tongue, which darts out of his mouth whenever an unlucky insect comes within reach.

“His tongue is fixed to the floor of his mouth just at his lower lip. It is forked at the end. When not in use, it lies folded back inside his mouth and points down his throat.”

Exercises on Lesson X.

1. Where are frogs, newts, and toads in winter-time?
2. How could you tell a toad from a frog?
3. What is the difference between young newts (tadpoles) and young
frogs (tadpoles)?
4. Write the life of a frog (or of a toad) as if told by the creature
itself.

XI.—UNDERGROUND STEMS.

Uncle George and his three young pupils had been to the woods. After tea he opened the metal box which he carried, slung by a strap over his shoulder, whenever he went out rambling.

This box had in it a pond-net and a couple of wide bottles. To-night it was half filled with plants.

Before laying them on the table, Uncle George washed the soil from their roots at the tap.

“Now then,” he said, “let me see how much you remember of our lesson in the woods. I will begin with Dolly”—and Uncle George held up a lovely white flower.

“That,” said little Dolly, “is the _wooden enemy_!”

Uncle George laughed loudly, and so did the two boys. Dolly laughed too—she did not quite know why. She was a merry little girl, who laughed whenever she got the chance.

“You mean _wood anemone_, dear, don’t you?” said Uncle George, as he stroked her pretty curly hair.

“Yes, I _mean_ that, Uncle George; but I can’t say it properly,” said Dolly, still laughing.

“Oh yes, you can if you try—wood a-nem´-o-ne. It is easily pronounced. Now Frank, it is your turn. What is this one with the great number of yellow petals, the spotted heart-shaped leaves, and the funny fat roots?”

“The pilewort, or lesser celandine,” answered Frank.

“Quite right! Now, Tom, here is one for you. This plant, you see, has broad kidney-shaped leaves with crimped edges, large yellow flowers, and a coarse round hollow stem. We found it, if you remember, growing in the mud at the edge of the brook.”

“It is the marsh marigold,” said Tom.

“Very good! Now this one?”

As he held it up all three answered at once—“The primrose!”

“We found this one also growing at the edge of the brook.” As he spoke, Uncle George held out a very pretty plant. Its flowers were of a pale pinkish blue colour. They were shaped like the flowers of the wallflower, but were smaller. The flowers were borne up upon a long stalk which sprang from a rosette of pretty little leaves.

“It is the _lady’s smock_,” said Dolly; “I remembered that one because it is so pretty.”

“Well done, Dolly!” said her uncle proudly. “Now, I think we have quite enough to go on with. Let us take these up one by one and examine and draw parts of them. First take the wood anemone. What do you call this?”

Uncle George pointed to the stout part of the plant that had been in the ground.

“The root,” said Frank.

“No, Frank!” his uncle replied. “But that is what I thought you would say. Now, tell us why you think it is the root.”

“Because it grows under ground.”

“But roots do not have buds upon them, Frank: and see! flower-stalk and leaf-stalk spring from it, while fibrous, or string like, roots hang down from it.”

“It must be a stem, then,” Frank ventured.

“It _is_ the stem,” said his uncle. “We have already seen that the creeping crowfoot and ground ivy have stems that creep along on the surface of the ground.

“Many plants have stems which creep along under ground. This is an underground stem; and this is another.” Here he pointed to the primrose.

“Why, I always thought that that pink thing was the root of the primrose,” said Frank; “but I see now that it is really more like a stem. It has marks upon it like scars.”

1. Caterpillar, Pupa, and perfect Insect of Tiger Moth
2. Caterpillar, Pupa, and perfect Insect of Magpie Moth
3. White (Cabbage) Butterfly, Male and Female, with Caterpillar and
Pupa

“These are marks where leaves once grew upon it,” his uncle remarked. “Notice that the primrose leaves form a rosette on the top of this underground stem.”

“Is there any reason for these plants having their stems under ground?” Tom asked.

“There is a reason for everything in nature, my boy. Can’t you see any reason for this yourself?”

“I see one, I think,” said Frank; “it enables the plant to creep out to new soil.”

“That is one very good reason, Frank. Now, why should it seek other soil?”

“For food!”

“That is right, Frank. Those plants which have underground stems seem to die down every autumn; but they are alive all the time under ground, safe from the frosts and bitter winds which kill tender plants. And they peep up in a new place in spring.

“Now I want you to tell me why these underground stems are swollen out so. It cannot be for strength, for creeping stems don’t require to be strong.

“Fetch me a raw potato, Tom, please!

“Now,” Uncle George continued, “tell me what this potato is.”

“It is an underground stem,” said Frank.

“Yes! Why is it swollen? What do we use the potato for?”

“For food. Oh, I know,” said Frank, “it is a food store.”

“Of course,” said his uncle. “It is a supply of food gathered up this year for next year’s plant. Look at the roots of the lesser celandine. I see Tom has drawn them. They are swollen. Are they roots, or underground stems?”

“They have neither leaf marks on them, nor buds,” said Frank, “I think they must be roots.”

“They _are_ roots,” said Uncle George, “but they are food supplies all the same.

“There are other underground stems that grow quickly. Good examples of these are mint, couch grass, and sand sedge. The underground stems of these plants grow so fast that they are always occupying new ground. They have therefore no need to store up a food supply like their slower growing neighbours the primrose, potato, anemone, iris, and many others.”

Exercises on Lesson XI.

1. Dig up a primrose plant, and make a rough sketch showing
underground stem, roots, and leaves.
2. An underground stem may be of use to a plant in three different
ways. Can you name them?
3. There are two distinct kinds of underground stems—those that grow
quickly and those that grow slowly. Name three of each kind,
and tell how they differ in shape.
4. Compare a potato with a horse-chestnut twig. Supposing your twig to
be swollen out with plant-food, what parts of it do the “eyes”
of the potato represent? What do the {scars/marks} near the
“eyes” represent?

XII.—CATERPILLARS.

“We found these upon the dead-nettle.” As he spoke, Frank opened a small cardboard box and showed his uncle half a dozen large, hairy caterpillars.

“Splendid,” said Uncle George. “We will just put these into the cage.”

Uncle George, who was a very good carpenter, had of late been busy in his spare time making a box or cage for keeping caterpillars in. He called it a _larva cage_.

It was a curious looking thing, something like a small meat-safe. Three sides and the top of it were covered with gauze. The fourth side was a large pane of glass. The gauze-covered side opposite to this opened as a door.

It was divided into an upper and a lower part by a shelf in the middle, and, by sliding in two pieces of wood, it could be divided into four tiny rooms.

Now that it was finished, Uncle George wanted to get it stocked, and his two nephews wanted it stocked too.

“Do you want any more of these woolly caterpillars?” Frank asked.

“No, Frank, but you can bring me in some more of a different kind. Or, better still, let us go out into the garden now and see if we can find any there.”

The gardener beamed with joy when Uncle George told him what they had come to the garden for.

“Caterpillars?” he said. “I wish you would take them all, sir. They are the worst vermin in the garden. Last year they left scarcely a leaf on my currant bushes.”

Our three friends went straight to the currant bushes. Here they found a good many pretty little caterpillars of a creamy colour, richly striped with orange, and dotted over with black spots. These, their uncle informed them, were the caterpillars or _larvæ_ of the magpie moth.

On the cabbages they found several caterpillars of the large white butterfly. These were bluish green in colour, with three bold yellow stripes running along the whole length of their bodies.

“What are these, Uncle George?” Tom asked, as he turned up a cabbage leaf and pointed to several white patches on its under side. The leaf next it was spotted just like it.

“Oh, Tom, how lucky we are! These are the eggs of the large white butterfly. Now we shall be able to follow up the whole life of this insect, and a wonderful life it is. Let us go right in and examine them. Take some cabbage leaves and some currant leaves to feed the hungry caterpillars with.”

“Our larva cage is now quite full,” said Uncle George, when he had put the caterpillars in.

“Why do you not put them into the same room, Uncle George?”

“There are two reasons for that, Frank. First, they live upon different kinds of food. The hairy caterpillar, or ‘woolly bear,’ as boys call it, feeds upon nettles, the cabbage caterpillar prefers cabbage leaves, while the currant caterpillar will only eat currant leaves.

1. Caterpillar and Eggs of Cabbage Butterfly.
2. Egg magnified.

“Second, the woolly bear will sometimes eat up his smooth-skinned friends. Now, get your glasses and have a peep at the beautiful eggs of the ‘large white’ or ‘cabbage’ butterfly.”

“Why, they are not at all like eggs,” said Frank, as he closely looked at them with his glass.

“What are they like, Frank?”

“They are like little pieces of carved ivory all shaped alike,” Frank replied.

“Yes, but that does not give us a very clear idea of their shape,” observed his uncle. “Come on, Tom.”

“They are like little Indian clubs with the handles cut off, only they are beautifully marked with long, slender ridges and cross bars.”

“That is really a very good account of them, Tom. They are arranged in patches. Count and let me know how many eggs are in each bunch.”

The boys counted all the groups of eggs, and found that there were eight eggs in some, nine in others, but that most of them contained ten or more.

“Now, how many egg patches are there?” asked Uncle George.

“There are seven patches on my leaf,” said Frank.

“And ten on mine,” added Tom.

“That is about one hundred and fifty eggs altogether,” said Uncle George.

“Has each of these bunches of eggs been laid by one butterfly?” asked Frank.

“It is more than probable that one butterfly laid the whole lot,” his uncle replied; “for the white butterfly lays, as a rule, over two hundred eggs.”

“That is about as many eggs as a hen lays in a year,” said Frank.

“Yes,” said Uncle George, “a good hen and a white butterfly lay about the same number of eggs in a year; but the butterfly lays all her eggs in one day.

“After laying her eggs, she dies. That is perhaps why she always lays them on the kind of plant which the young caterpillars can feed upon when they hatch out.

“Let us look at the caterpillars now. We need not take them out, as we can easily see them through the glass side of the cage.

“Notice that the body of the cabbage caterpillar consists of a round, dark coloured head and a number of broad, ring-like divisions. How many of these divisions are there?”

“Twelve,” said Frank, after counting carefully.

“Right!” said his uncle. “Now, about legs—how many are there?”

“There are three pairs of legs on the first three divisions of its body, and a pair of shorter and stouter legs on each of the sixth, seventh, eighth, and ninth divisions, making seven pairs of legs altogether,” Frank answered.

“That is quite correct, Frank, and I am glad you noticed the difference between the first three pairs and the others. The first three pairs are the creature’s real legs. The others are false or temporary legs.”

“There is a row of black spots on the yellow band along its side,” observed Tom.

“These are its breathing-holes, Tom. We breathe by our lungs only, but caterpillars and insects have breathing-tubes all over their bodies.”

“The woolly bear and the cabbage caterpillar move about in the same way,” said Frank. “But look at those currant caterpillars, Uncle George, what a funny way they have of getting along!”

“These belong to a kind of caterpillars known as ‘loopers,’” said his uncle. “They move about by looping up their bodies in this strange manner.”

“I do not like to handle those hairy caterpillars,” Tom remarked. “Why are they covered with those nasty long hairs?”

“You have just given the reason, Tom. You don’t like to touch them on account of these hairs; neither do animals. No bird will eat one of these. If he does, he will never eat another.

“Notice how they coil up like a hedgehog when they are touched. This makes them more difficult to swallow. Just imagine how a bird would feel with one of these ticklish customers stuck in his throat, eh?

“Now, boys, make a sketch of one of the tiny eggs, also one of the big cabbage caterpillar, and then we will go out and have a game of cricket on the lawn.”

Exercises on Lesson XII.

1. Where would you look for the eggs of the white butterfly? Why are
they always laid upon the same kind of plant, and why _under_
the leaf?
2. Explain how caterpillars breathe.
3. Take any caterpillars you find. Observe the leaves you find them
feeding upon. Give them fresh leaves every day, and watch how
they grow.
4. Why has the “woolly bear” caterpillar got a hairy coat? What does
he usually feed upon?

XIII.—THE WHITE BUTTERFLY.

Uncle George had to go from home for a week, and his two nephews went part of the way to the railway station with him.

As they were about to take a short cut through the wood, Uncle George went up to a huge beech tree. He looked very closely at its grey trunk for a time, then stepping back from it about three yards, exclaimed:—

“Come here boys! Stand beside me, look closely at this tree, and tell me if you see any strange objects sticking to the bark.”

After staring at it for some time, they both declared that they could see nothing upon it.

“Go nearer—nearer still! Now, do you see anything?”

The boys shook their heads.

“Go quite close up to the trunk and examine it,” said Uncle George.

“Oh,” said Frank suddenly, “I see queer things like grubs, coloured almost exactly like the bark. Some of them are lighter in colour.”

“Look carefully at those lighter ones, and you will find that they are just empty cases.”

“So they are,” said Frank, as he touched one with his finger and saw it crush up.

“Notice how they are fixed to the bark!” said Uncle George.

The boys watched as their uncle placed his pencil under one of the darker coloured objects, and saw that it was slung up to the tree by a loose silken girdle round its middle, while a tuft of fine threads fastened the lower end to the bark.

Suddenly, as if it were annoyed at being touched by the pencil, the lower half of the object moved from side to side with rapid jerks.

“Why, it is alive,” said Tom.

“Yes, of course it is,” said his uncle. “This is another lucky find.”

“What are they?” Frank asked.

“Can’t you guess, Frank? Don’t you remember my telling you that all the insects were asleep in their cases during winter.

“Each of these darker coloured cases contains a white butterfly. They have been here all winter, and they are just about to hatch out.”

“How do you know that, Uncle George?”

“I know it because the empty cases tell me that some of the butterflies have just hatched out. This is what your cabbage caterpillar becomes after he is tired of feeding.

“You have now seen three different stages of the life of this insect. First, the curious eggs laid on the under side of the cabbage leaf; next the greedy caterpillar; and now, the chrysalis or _pupa_ stage.

“The caterpillar goes to sleep in autumn as a hard-cased chrysalis, and wakes up in spring a beautiful butterfly.”

“How strange,” said Frank. “And will our caterpillars remain caterpillars until autumn, and then tuck themselves up like this and go to sleep for the winter.”

“No, Frank! our caterpillars will go into the chrysalis state in a week or so, and hatch out as butterflies in August. These August butterflies will lay eggs. The caterpillars from these eggs will turn into _pupæ_ in September.

“These September pupæ will supply the white butterflies of next spring and summer. Put some of these into your box. Watch then carefully, and you may be lucky enough to see the white butterfly coming out of his winter case.”

“I cannot understand,” said Tom, “how a big white butterfly can be inside so small a case. It must be very tightly wrapped up.”

“So it is, as you will see,” said Uncle George. “Good-bye, boys! and mind, when I come back, I shall expect to see notes and sketches of all that has taken place in the larva cage during my absence.”

* * * * * * * *

“Won’t you let your uncle take his dinner first,” said Frank’s mother, as she hung Uncle George’s overcoat up in the hall.

“No, mother! he must come at once,” said the excited Frank. “There’s a butterfly just coming out.”

“Oh, I must come and see that,” said Uncle George; and he allowed his eager nephews to drag him towards the larva cage.

By the time they got to the cage the butterfly had hatched, but they were in time to see it unfurl its wings. The wings were crumpled and twisted, but the creature slowly straightened them out to dry in the sun.

“We saw it burst its case,” said Tom. “First a small slit appeared at the head end. This slit grew larger. Then the butterfly’s head and feet appeared. It squeezed its way and was just half way out, with its wings crumpled round it, when you arrived.”

“I arrived just a minute too late, then,” said his uncle.

“Oh, and the eggs have hatched too,” said Tom. “Look at them now, Uncle George!”

His uncle looked, and saw that the white patches of eggs had given place to larger patches of little active, dark coloured maggots.

“We want to know what has become of the lovely carved shells of the eggs,” said Tom.

“They have been eaten up,” his uncle replied. “From the moment a caterpillar is born he does nothing but eat—eat—eat. He begins by eating the shell of the egg he comes out of.

“For the first week of their lives these tiny caterpillars feed together in small bands, and they grow so fast you can almost fancy you see them growing. After they have grown to a certain size, each caterpillar starts out for himself.”

“Do you see the three butterflies that have hatched out?” asked Tom.

“Yes, I see them. There are two females and one male,” said Uncle George.

“How can you tell males from females?” asked Frank.

“Oh, that is easy enough,” Uncle George replied. “The females are larger, and have two big black spots on each of their front wings. But I only see eight of the large cabbage caterpillars. We put in twelve, I think.”

“Look!” said Frank, pointing to the roof of the cage.

“Ah, yes, I see them. Two of them have passed into the pupæ stage, and are slung up by their silken belts to the wall of the cage.

“The other two are spinning silken belts round the middle of their bodies, if they have not already done so. After this belt is finished they will slowly slip their useless green skins off, and finally get rid of them by sharply jerking the tail end of their pupa cases.”

“Yes, we watched those other two do that,” said Tom.

“Notice,” continued Uncle George, “that all your big cabbage caterpillars have lost their yellow stripes and are now of a bluish green colour. They have stopped feeding, and are now dull and sleepy. This indicates that they are about to enter the pupa stage.”

“But look at the currant and the hairy caterpillars, uncle,” said Frank.

“My dear boy,” said Frank’s mother, “Uncle George must really have food and rest after his long journey. He will hear about the other caterpillars some other time.”

Exercises on Lesson XIII.

1. Explain why the pupæ of white butterflies are coloured like the
objects they are attached to.
2. Write the life of a white butterfly, and illustrate your
description with sketches of caterpillar, pupa, and butterfly.
3. The life of an insect is divided into four distinct stages. Name
them. Which is the longest stage in the case of the white
butterfly?
4. Describe, as you have observed it, the behaviour of a caterpillar
as it passes from the larva to the chrysalis form.

XIV.—THE TOILING CADDIS.

“Look here, boys,” said Uncle George, “you have been paying nearly all your attention to the larva cage during my absence, and have forgotten the caddis worms.”

1. Caddis Cases.
2. Larva out of Case.
3. Pupa.
4. Caddis Fly.

Uncle George made believe to be cross.

“We changed the water every two days,” said Frank.

“Yes, I know. But you have not reported any changes in the creatures themselves. What has been going on in the larva cage has also been going on here in the water, for caddis worms are simply water-caterpillars. You nearly missed something of very great interest.”

Uncle George laid three saucers on the table, and continued:—

“We are going to look into the life of the caddis fly to-day; but before I take them out of the water, I want you to tell me what you have noted about them up to now.”

“They are always climbing up the water weeds,” said Frank.

“They are always adding to their cases,” said Tom.

“Some of them have died,” said Frank.

“What?” said his uncle. “Do you mean these at the bottom of the tank? These are not dead, they are only asleep. Put your hand in, and take some of these out.”

“Their cases are stuck to the pond weeds and to each other,” said Frank, as he lifted a few out, and placed them in a saucer.

“Ah, I have it, Uncle George! They have gone into the pupa state. Is that not so?”

Uncle George nodded.

“Look!” exclaimed Tom. “There are things like earwigs floating on the water.”

“Never mind these just now, Tom,” said his uncle. “I am coming to them by and by. Observe the wonderful cases which the caddis worms have made for themselves.

“Here is one whose case, when we found him, was made of neatly cut pieces of water rush. He has almost doubled the length of his case since then; for see, the front half is made of cut stalks of water weed neatly arranged.”

“He has got a fine collar of green pieces round his neck,” Frank observed.

“Why are they always adding to the length of their cases?” asked Tom.

“Because they are always growing,” said Frank.

“That is the reason,” said Uncle George; “and they grow so fast that they have actually to work hard at building.

“Observe those that make their cases out of tiny shells and stones. They have made free use of the coloured beads and small pieces of coal which we put in.”

“How do they manage to stick these things together?” asked Tom.

“A caddis worm is a busy creature,” his uncle replied. “He does two things besides eating and growing. With those strong pincers, which you see at his head, he saws off pieces of weed.

“Near his mouth he has got a kind of loom for spinning silk. These pieces are stuck together with silk, which is a gluey substance when it first comes from the creature’s body.

“These rough cases are lined with silk.”

“Why does he have to make a house for himself, and carry it about with him?” said Frank.

In answer to this, his uncle took out a few of the active caddis worms, and placed them in a saucer with water. He held one up.

“You see,” he said, “his case is open at both ends. Now, if I tried to get him out from the front, I should never manage it. This is the way to get him out.”

As he spoke, Uncle George pushed the head of a pin into the tail end of the case, and the creature scrambled out at once.

“It is too bad turning you out of your cosy room, Mr Caddis,” Uncle George observed; “but you’ll go back again as soon as you get the chance, won’t you? I want my nephews to understand why you work so very hard.

“Now, Frank, you can answer your own question, I think—‘Why does the caddis worm build a house?’”

“Because he has a soft body.”

“Quite right. But why is he forced to protect his body?”

“Fishes would eat him.”

“Right again, Frank. If trout could speak, they might tell you that the sweetest morsel in the stream is the caddis worm. Now, take your lens, please, and tell me something about him.”

“His body is divided into rings, and there are the same number of them as we found in the caterpillar.”

“Very good, Frank. Now give Tom a chance.”

“His head and the first three divisions of his body are hard cased. They are black and yellow in colour.”

“He has six legs,” said Frank, “and they are attached to the first three divisions of his body.”

“What about the last division of his body?” Uncle George asked.

“Oh, how funny!” said Frank. “It is divided into two large things like horns.”

“These,” said his uncle, “are the hooks by which he fixes himself so firmly in his case.”

“And what are all these curious big bristles for?” asked Tom. “They are all over his body.”

“These are his breathing organs,” Uncle George answered. “The caterpillar, if you remember, had breathing-holes along the sides of his body. By moving his long body, the caddis worm causes a constant current of water to pass through his dwelling.

“Look at the fourth segment of his body. How does it differ from the others?”

“It is the broadest segment,” said Frank, “and there is a stout rounded thing in the middle of it.”

“Yes,” his uncle replied, “and if we can get him turned on his back we shall see two more of these stout outgrowths below, one on each side of the same segment. This is really very clever. By it the animal keeps himself in the middle, so that the current of water must flow all around him.

“Now, look at the case of a sleeping caddis.”

“The front of the case is closed,” said Frank.

“How is it closed, Frank?”

“Well, there is a network of threads over it,” answered Frank.

“Yes; you see a caddis worm cannot do without fresh water, even when he is asleep; so, before going to sleep, he builds a grating over the entrance.

“When he wakes up, he has quite a new shape altogether. And this brings us to those things which Tom said were like ‘earwigs.’ There are five of them floating on the water, and two of these are dead. If you look, you will find five empty caddis cases in the tank.”

“How does he get out of the case?” inquired Tom.

“Easily enough. Look at the strong pair of pincers he has got for cutting his way through the silken grating with. No longer burdened with his heavy case, he floats up to the surface. He crawls up out of the water into the air.

“If there are no rushes or floating leaves about, he is sure to drown; for your caddis is no longer a water insect, but a fly inside a thin skin.

“Now, boys, I am going to show you something wonderful.”

Uncle George then took out the three living pupæ that were floating on the water, and placed them on the table. The boys watched them for a long time.

They were beginning to get impatient, when suddenly the skin of one of the creatures burst along the back, and a lovely little fly, with brown, gauzy wings and long feelers, came out.

After airing its wings for about a minute, it flew to the window. The other two acted in just the same way.

“Now, my dear boys, I think you know something about the life of the caddis fly. For a whole year of his life he is a crawling water insect, then, for about a single day, he is a lively fly.”

“How does the caddis larva first get into the water?” asked Frank.

“As an egg, Frank. The female caddis fly lays her eggs in the water. She sometimes even crawls down right into the water to lay them.

“A tiny caddis grub, no bigger than this pin-head, comes out of each egg. As soon as he hatches out, he begins to build his case, to eat, and to grow; and from the moment of his birth up to the closing up of his tube, he is scarcely a moment idle.”

Exercises on Lesson XIV.

1. Turn a caddis worm out of his case in the way described in the
lesson. Place the insect in a saucer half filled with water,
and make a rough sketch of it.
2. When you have finished your sketch, place the empty caddis case in
the saucer, and watch how the creature gets into it.
3. Make two columns by drawing a line down the centre of a page of
your note-book. In the first column, describe the structure of
the caddis larva and fly; in the second, that of the cabbage
caterpillar and butterfly. Compare them.
4. In the same way describe the _mode of life_ of the caddis fly
(Column 1), and of the white butterfly (Column 2).

APPENDIX.
HINTS TO TEACHERS.

BUDS.—Twigs of beech, horse-chestnut, lilac, and hawthorn ought to be taken in in December and placed in water. They should have as much warmth and light as possible.

Willow twigs (for catkins) might also be forced in this way.

SEEDS.—Seeds should be soaked for twenty-four hours and then sown in sawdust in boxes 4 inches deep. They should be sown in presence of the pupils.

In winter these boxes should be kept on the hot pipes in school. The sawdust should not be allowed to get dry, neither should it be deluged with water, but kept evenly moist if possible.

Be careful to use water _not colder than the temperature of the room_ in which the seeds are grown. Nothing checks growth more effectively than chilling with icy-cold water. It is a good plan to keep the watering-pan full of water near the hot pipes, refilling it always after use.

Seeds germinate best in the dark, but whenever the plumule shows above the sawdust, the box containing them should be placed in the light. Sufficient seeds should be sown at one time to supply a plant to each pupil once a week for at least four weeks. A number of seeds or plants should be dug up once a week and sketched by the children. Each sketch should be compared with that of the previous week, and all changes duly noted down.

The best seeds to grow are:—Broad bean, common or “large white” maize, runner bean (“Painted Lady”), French bean, kitchen pea (“Stratagem”), and white mustard.

A few seeds of white mustard should be sprinkled on a small piece of moist blotting-paper, and covered over by a small glass bell-jar or an inverted tumbler. In less than a week the root-hairs may be seen.

If hot-water pipes are available, the following seeds should be grown, as their germination is interesting:—date stones, walnuts, chestnuts, almonds, cherry stones, orange pips, seeds of cucumber and sunflower.

After maize and bean (or pea) plants have reached the height of 5 inches, they should be transferred to bottles of tap water—as described at the end of Lesson VI.—and the continuous growth sketched and noted from week to week.

POND AND DITCH HUNTING.—Make a ring of stout brass wire about 8 or 10 inches in diameter, and to this attach a bag net made of mosquito netting not more than 9 inches deep. In making the wire ring, leave attached to it about 5 inches of the twisted ends of the wire. Such a net as this can be easily carried and quickly attached to the end of a walking-stick by means of a piece of string.

The best “finds” are often made by sweeping the net under banks and among pond weeds.

FROG SPAWN.—Frog spawn is abundant in ponds and ditches everywhere in March. It should be kept immersed in as much water as possible in a large vessel, preferably of glass. Whenever the water show signs of fouling, it should be changed; but, as changing water containing tadpoles is somewhat difficult, the fewer changes the better.

As in the case of seed growing, the development of the tadpole should be learnt by weekly sketches and notes.

NEWTS.—Newts can be taken with the gauze-net or in the following way:—Tie a piece of small worm on to the end of a cotton thread fastened to the end of a willow or hazel switch. Cast into the part of the pond where the newts are, and await results.

Live newts, fish, frog spawn, etc., may be obtained from Messrs Willson, Live Stock Providers, 37 New Oxford Street, London; Thomas Bolton, 25 Balsall Heath Road, Birmingham, and other dealers. Newts should be fed once a day on pieces of small worms.

CATERPILLARS.—Caterpillars and pupæ, if not obtainable in local woods, fields, and gardens, can be had from Messrs Watkins & Doncaster, 36 Strand, London, and others.

CADDIS LARVÆ.—Caddis worms are to be found in almost every stream, pond, and ditch. Most of them are vegetable feeders: therefore a plentiful supply of water weeds should be placed in their tank. Carnivorous caddis worms may be fed on small pieces of raw meat. (See Stickle-backs.)

STICKLE-BACKS.—Stickle-backs are common in canals and streams. They are easily caught with the net. They should be fed once a day on grated biscuit, and occasionally on raw meat. The meat should be chopped very fine, and then pressed through a piece of perforated zinc. Very little food suffices. If too much is put in, the residue should be removed by means of a glass tube, as described in Lesson IX., p. 56. If no green water plants are obtainable, the water should be changed at least every second day by means of a siphon. Once a month is quite often enough if sufficient green plants are kept in the tank and decaying matter carefully removed. Do not over-stock—few fishes and much water is the rule.

WATER PLANTS.—It is best to take the water plants which are found growing locally. The following are fairly common:—_Elodea canadensis_, water millfoil; _Potamogeton_ (_nitens_, _crispus_, or _filiformis_), “water soldier”; _Vallisneria spiralis_, _Chara_, _Nitella_, water star-wort and watercress. A good selection of excellent aquarium plants are advertised at a cheap rate by the Solway Fishery Co., Dumfries. Water plants, if not rooted in the tank, should be renewed occasionally.

LARVÆ CAGE.—Take four square pieces (about 1½ inches square) of wood, each a foot long, and nail or screw them upright into the four corners of a square piece of ¾-inch deal measuring a foot each way. Stretch mosquito netting over sides, end, and top, arranging that one side can be opened. This can be managed by fastening the last fold of netting to one of the upright posts by three drawing-pins. Fresh leaves should be supplied daily. For those caterpillars which pupate in the soil, a shallow earthenware flower-pot—known in the trade as a “seed-pan”—should be supplied. The seed-pan should be filled with soil, the pupæ placed on the surface, and a layer of moss placed over them. Once a week the moss should be dipped in water, squeezed almost dry, and replaced on the pupæ.

AQUARIUM.—Procure from a local florist or seedsman what is known as a “propagating bell.” These cost from 1s. up to 2s. 6d. A block of wood 12 inches square and 4 or 5 inches in thickness is also required. Bore a hole about 2 inches in diameter right through the centre of the block, to hold the knob of the bell. Then, with a gouge chisel, make a saucer-shaped hollow round the hole, to roughly fit the rounded end of the bell. Before fitting the bell into the block, interpose a thin layer of moss.

This makes an excellent aquarium—elegant and serviceable. Keep the aquarium in a window, but shade it from bright sunlight.

Transcriber’s Notes

--Retained publication information from the printed exemplar (this eBook
is in the public domain in the country of publication.)

--Only in the text versions, delimited italicized text with
_underscores_.

--Silently corrected several typos.