the tail. In the middle of each scale, on the lateral or side line of
the fish, is a little groove or canal. It runs in the direction of a
line from head to tail. Let us see what it is for.
Have you noticed how slippery fishes are? Is it not hard to hold them?
If you rub your finger hard down their bodies, you rub off a quantity
of slime, or stuff like glue, or thin paste. This glue-like stuff is
made near the mouth of the fish. It is supplied to the scales by little
tubes near the mouth. It runs through that little canal in each scale
in a line upon the side of the fish.
This slimy stuff helps the fish to slide easily through the water. It
keeps the scales limber and healthy. It keeps the body supple. It
helps the fish to slip away from creatures that seize it. Also, I am
sure, it helps the fish to slide easily down the throats of birds,
animals, or fish that capture it!
The fact that the scales all lie turned from the head to the tail of
the fish, also makes it easy for birds or other fish to swallow it. But
if a fish is partly swallowed, it cannot be readily cast out, for its
scales rising, make a rough surface, and hinder it. I suppose that was
why the alwife duck I told you of could not get the partly swallowed
fish out of her throat.
Each kind of fish has its own especial shape and color of scales. Some
are pointed, some are rounded, some are flat, some are curved, some
are three-cornered. Some fish have no scales. Some have such tiny ones
that you will not notice them unless you look sharp. Some fish, as the
sturgeon, have great bony plates, like large limpet shells, laid in
lines up and down the body.
Fish not only have their own especial shape of scales, but their
especial color, and such colors have their especial place on the fish.
One flat, brown fish has all the under side of its body white, but
spots of red, like sealing wax, are laid all over the brown side, as if
you had dropped red wax upon it.
When you see a smoked and salted herring hung up for sale, you are not
likely to guess what a beautiful thing it was, when living in its water
home. It had a coat of blue, green, and silver, and gem-like eyes. The
eye of a dead fish is sunken and dull. The eye of a living fish is
full, and gleaming with light.
There is a little fish called a wrasse which looks as if made out of a
rainbow. It is dressed in bright blue, gold, bronze, and white.
The red bream is of a fine rose-red color, with silver sides. Its
luminous eyes are set in golden rings. The perch has dark, shining
bands on its silver coat, and it has gay, red fins. The gray mullet is
a quaker fish, trim, grave, quiet in its style, but lovely in its shape
and in the rainbow lights along parts of its body.
Once I saw in the water a fish called a gurnard. He seemed to have
borrowed a sunset to dress himself in. His scales were deep red and
bronze. There was a vivid blue on the edges of his fins. The fins were
in shape and coloring like a butterfly’s wings.
I never saw a boy who did not think that a trout was one of the
prettiest things ever made. Very much of the beauty of fishes lies in
the wonderful scales.
But you must examine scales for yourselves. If you have a microscope to
look at them with, you will be full of delight and surprise at what you
see. Once I looked through a very powerful microscope, and thought I
was looking at a lump of half-melted gold set full of fine jewels. But
it was the scale of a fish.
I will now leave the scales, and tell you a little about the teeth of
fish. Fish have a great many teeth. Their mouths are for the most part
hard and horny, and so covered with teeth that it is not likely that
they have very much sense of taste. Still there are some kinds of fish
that are almost, if not quite, toothless.
If you open the mouth of a sea-trout you will find that it is set
entirely round, with sharp, strong teeth. Then if you stretch the mouth
open and look into it, you will see that there is another row of teeth
set all round a bone inside the upper jaw. Look still farther in, and
you will see a row of teeth on the middle bone in the roof of the
mouth. Look still beyond, and you will see a row of teeth on each side
of the tongue.
Some fish, besides all these teeth, have the tongue quite covered with
teeth. Others, that eat vegetables, have little fine teeth all down
the sides of the throat. The French call such teeth as these, “teeth
in the velvet.” Some fish have the entire mouth and throat lined with
teeth.
These teeth may all be alike, not some “double” and some “single” as
you have. But sometimes fish have teeth of different patterns. The most
common form of teeth in fish that live on fish or other animal food,
is that of a slim cone, bent a little inward to hold firmly the fish
caught, so that it cannot slip away.
The fish that feed on weeds have short, roundish teeth with a flat top,
to make a good mill with which to grind or crush their food. Fish that
eat insects do not need such large teeth. They have a great number of
little teeth almost as fine as hairs. Rows of these teeth look like a
little brush.
Some fish are said to have “mill” teeth, as the carp, because their
large flat teeth roll upon each other like the stones of a mill
grinding grain.
The ray fish, that feed on crabs, shell-fish, and flat fish, need very
strong teeth for crushing such food. If you should look into their
mouths, you would see that they are made like a mill, and the upper and
under teeth roll against each other and crush fine all that is between
them. By looking at the mouth of fish and examining its teeth, you can
find out what kind of food it used, just as by looking at the beak and
claws of a bird, you can tell what were its habits and food.
Some fish have the inside of the stomach thick and furrowed, very like
the gizzard of a fowl. This is to aid in cutting or grinding up the
food. The teeth of a carp have much the appearance of the teeth of
sheep and cows, only they are much smaller. They work against a plate
of gristle in the roof of the mouth and reduce the food to pulp.
The strong, sharp teeth of fish are used not only for eating their
food, but for biting and fighting other fish. Two great salmon have
been known to fight until one was killed. The dead one was found to be
badly wounded and torn by the teeth of its enemy.
Pike have very sharp, strong teeth, and a big pike has been known to
seize hold of the foot or nose of a dog, fox, or other animal, that
came to the water’s edge to drink.
The mouth of a dog-fish is set back on the under side of the head. This
mouth has a row of strong, sharp teeth all round it. When the fish
seizes its prey or its enemy with its teeth, it whirls itself over, and
this action enables it to tear out a large piece of the flesh held by
its teeth.
LESSON XLVI.
BIG AND LITTLE BROTHERS.
Yesterday, as I was going along the street, I saw a large globe full of
tiny fish. They were from one to two inches long. I stopped to examine
them. They were sticklebacks. You must know that little Mr. Stickleback
is a very pretty and curious fellow, and well worth buying.
[Illustration: THE LITTLE HOUSE BUILDER.]
Looking into this globe made me think of some of the queer things I
have heard and seen of this little fish. Shall I tell you about him?
The stickleback gets his name from the fact that some of his fins,
one on the back and one on the lower part of the body, have changed to
spines or thorns. Different kinds of stickleback have three, four, ten,
fifteen, of these thorns.
This little fellow is one of the smallest and prettiest of fishes. He
is slender, and from one to three inches long. The general length is
about an inch and a half. His body is silver below, green and purple in
bands on the back, and red and gold on the head and sides. His fins are
thin as finest silk. I never saw a prettier little creature.
The stickleback is very greedy, very fearless, full of courage, very
affectionate, and of all fishes is the most devoted parent. Finally,
the stickleback can build a house.
The colors of the stickleback brighten or fade according as he feels
glad or sad. If he has lost his mate, his home, or his young ones, or
if he has been beaten in a fight, he swims off to hide, and his colors
grow dull. If he has beaten his enemy, if his children and mate are
quite safe in the little house where he has put them, he gleams and
glows like a rainbow.
Sticklebacks are so fearless that when they are in a pond no noise or
shadow will alarm them. You can even catch them without a hook just by
dropping among them a string with a worm on it. You may pull up the
string with two sticklebacks fast, one on each end of the worm. Little
English boys take this way of catching these tiny fish for their globes.
When put into a globe or box, they fight sharply at first. They strike
each other with their spines, whirl, dart, pretend to be beaten, and
then leap back to the fight. They are real little soldiers. Finally,
when they have found out which of them all is the strongest, each one
chooses his own corner, or shelter by a stone for a home, and defends
that against all strangers.
The different varieties of sticklebacks build different kinds of
houses. One makes a nest like a muff among water-weeds. I will tell you
of one kind of nest. The little fish carries straws and bits of grass
and moss, and tucks them down into the gravel and sand. He glues them
with the glue from his skin.
While he is at work he holds and carries his material with his mouth,
and presses it into place with his body. Having laid a floor, he builds
a little hut of woven fibres and moss. This hut is about as large round
as a twenty-five-cent piece. A little door is at the top. He tries the
strength of his house by stirring up the water near it with his tail.
When all is done Mr. Stickleback swims off to find his mate. He seems
to tell her that the house is ready. She is a lazy little creature, and
does nothing but frolic in the water. She goes along to the new home,
and goes in to lay some eggs there. Mr. Stickleback proudly swims up
and down before the home to keep foes away.
The little mate being fond of play does not like to stay in the house
long. She lays a few eggs about the size of poppy seeds. Then she bites
a hole in the house and runs away! Next day little Mr. Stickleback goes
to find her, and coaxes her back. This goes on for several days, until
a great number of bright yellow eggs, like seeds, are laid in the nest.
After this, it is a whole month before the little fish will hatch.
Meantime other fish and other sticklebacks will eat them, if they get
the chance. All that month the kind, brave little stickleback swims up
and down near his nest, and drives off enemies. He will let no fish,
not even his mate, come near his treasure.
Finally, out come the wee, wee fish. Now the poor little father has a
harder time than ever. The other fish want to eat up the young fry.
The food of sticklebacks is grubs, tiny insects, and very small fry. As
they are very hungry and greedy, they are on the watch to pick up the
new little fish. But the stickleback, however hungry, never eats his
own little ones. He leaves such vile conduct to the dog-fish.
As the little ones grow, they are very active, and want to stray away
from their home. Their father knows they would get into danger, so he
watches, and chases each runaway back into its home bounds, where he
can take care of them all.
Finally, the little ones are so nearly grown that they can fight for
themselves. They can pick up their own food, and make their own houses.
Then they are allowed to go off and swim where they choose.
As I have told you about a very little fish, I will now tell you
something of a very big fish. The sturgeon is a great fish which lives
in the waters of many countries. He is found in some of our rivers. The
body and head of the sturgeon are partly covered with five long lines
of great bony plates. These plates are grooved, and have a sharp point
in the centre. They make good armor.
Sturgeon are fond of playing and leaping from the water. They are often
speared by people standing on rocks or in boats. I have seen very big
ones taken from the Niagara River. In the Ohio and Mississippi the
curious spoon-bill or paddle-fish sturgeon are found. In some of our
other rivers the shovel-headed sturgeon lives.
The flesh of the sturgeon is good for food. The Russians make isinglass
from the air bladder of the sturgeon, and one or two kinds of food are
prepared from its roe and flesh. Of the isinglass prepared from the
sturgeon, jelly is made. Glue is very plentiful in the skin and bones
of the sturgeon, and a kind of food is made from the spinal marrow.
I need hardly tell you much about the uses of fish. You all know that
they form a large part of the food of men, and many birds and beasts.
Glue is made from fish-bones and skins.
From many fish are made those substances that I told you farmers put
upon their land to restore the minerals eaten out by the plants.
Oil is also made from fish. From parts of the cod an oil very useful
for medicine is obtained. From other fish, lamp oil and machine oil
are pressed. A little fish in the Caspian Sea is so oily that when it
is dried its body burns with a clear light. These dried fish are used
as candles. When the Cossacks get hungry, and have nothing else for
supper, they eat their fish candles.
That terrible fish, the shark, is very useful after he is dead.
From his fins, fine gelatine is made. From his skin, a leather-like
substance called shagreen is prepared. Shagreen is used in polishing
wood, and for covers of portfolios, instrument-cases, and the like.
From the bones of the shark, buttons and ornaments are made, and very
costly canes from his backbone. His teeth are very hard and white, and
are often mounted in gold and sold for ornaments.
There are many large and interesting books about fisheries,
manufactures of articles from fish, and about the various kinds of
fish, and their habits and uses. I hope you will try to get some of
these books to read. In fact, I hope you will pursue for yourselves all
these studies in nature which we have begun in the Nature Readers.
REVIEW LESSONS.
I.
1. What are some of the things which we get from the earth?
2. Why do we say “Mother Earth”?
3. What do we say are the eldest children of Mother Earth?
4. What is a plant?
5. What is the chief food of plants?
6. What are some of the things that plants can do?
7. How do animals get most of their mineral food?
8. Do plants take their food in liquid or solid form?
9. What partners have plants taken?
10. What is the business of plants?
11. What good does that business do us?
12. How large are some of the largest plants?
13. How small are some of the smallest plants?
14. What can you say of the length of a plant’s life?
15. What two great divisions of plants are there?
16. What are the six parts of a perfect plant?
17. What is a tendril?
18. Are any of the parts of a plant ever wanting?
19. Of what use to a plant is the root?
20. What are the true roots of plants?
21. What are these thicker parts which are usually called roots?
22. What is a plant stem? Of what use is it?
23. Tell me something about leaves.
24. With what does a plant begin and end?
25. Have plants more than one crop of seeds?
26. What is an annual plant?
27. Will you describe the sprouting of the seed?
28. What is a stamen?
29. What is a pistil?
30. Describe the seed-case.
31. What are the only really necessary parts of a flower?
32. Where does the growth of a plant begin?
33. What is a hardy seed?
34. How do plants grow?
35. What can you say about the plant’s need of moisture?
36. What is the blood of the plant?
37. What two kinds of sap are there in a plant?
38. Tell me about the tubes and cells.
39. Through what does the plant breathe?
40. How does the sap get changed in the leaf?
41. What can you say about starch in plants?
42. What about sugar?
43. How does the plant prepare mineral food for you?
44. Will plants thrive in the same soil year after year?
45. How does the farmer rest his fields?
46. How does he give more food in the fields to the plants?
47. What is a seed?
48. Describe an egg.
49. Describe a seed.
50. What can you say of the shape and color of seeds?
51. How are seeds carried about?
52. Tell me something about leaves.
53. Tell me how plants breathe.
54. What is the work of leaf-green?
55. What about carbonic acid gas in the air?
56. What is the plant’s work in purifying the air?
57. What can you tell me of color in plants?
58. What are some of the dyes we get from plants?
59. What motions have plants?
60. What is the cause of motion in plants?
61. What can you say of climbing plants?
62. Describe the strawberry plant.
63. Describe the walking fern.
64. What can you tell me of coal?
65. What is the use of pollen in the plant?
66. Are stamens and pistils always in the same flower?
67. What is necessary to the production of good seed?
68. How do insects convey pollen from flower to flower?
69. What has the flower to tempt insects?
70. What has the plant to keep away certain insects?
71. Tell me about the methods of insects in getting honey.
72. What plants have the pollen carried by the wind?
73. Why does the insect visit the flower?
74. Of what color are the flowers that need night-flying insects?
75. What can you say about the scattering of seeds?
76. How are some seeds blown about?
77. How do birds help in carrying seeds?
78. What is there about seeds to attract the birds?
79 What can you tell me of air-plants?
80. How do they get their nourishment?
81. Tell me something about water-plants.
82. What two shapes of leaves do some water-plants have?
83. Of what shape are most of the leaves that grow under water?
84. Why do they have these fringe-like shapes?
85. Of what shape are leaves that lie upon the water?
86. What kind of leaves have plants that grow in sand?
87. What use do these leaves serve?
88. Why are most plants that grow in sand prickly?
89. What can you tell me of a cactus-plant?
90. What long name have animal-eating plants?
91. What kind of living things do these plants catch and eat?
92. Tell me about the sun-dew.
93. Tell me about the Venus’s fly-trap.
94. Tell me about the pitcher-plant.
95. How do plants foretell changes in the weather?
96. What plants are the best weather prophets?
97. What is the reason of this closing before rain?
98. Of what use is this habit to the flower or seed?
99. Describe a flower clock.
100. Tell me about the hours when some plants open and close.
101. Will these hours of opening change with the time of year?
102. What is it that causes this opening and shutting?
103. Tell me about the sleep of leaves.
104. Of what use is this sleep to the plants?
II.
1. Describe a grasshopper.
2. What is the meaning of his various names?
3. How does the grasshopper make his music?
4. What can you say of Mrs. Grasshopper’s sword?
5. Do all grasshoppers live in the grass?
6. Are the head and chest of an insect in the form of rings?
7. To what order does the grasshopper belong?
8. How many straight-wing families are there?
9. How are they sometimes divided?
10. Tell me about the grasshopper’s legs.
11. Describe his wings.
12. What do grasshoppers eat?
13. Where are the grasshopper’s eggs laid?
14. Tell me how the grasshopper changes from egg to full-grown
grasshopper.
15. Can you tell me of any of his queer ways?
16. Describe some grasshoppers to me.
17. Does the grasshopper migrate?
18. Does the grasshopper live alone?
19. What insect is the robber cousin of the grasshopper?
20. Tell me how a locust differs from a grasshopper.
21. What can you tell me of the numbers of locusts?
22. Tell me what harm locusts do.
23. What means are taken to destroy them?
24. What can you say about their size and color?
25. What insect is the grasshopper’s merry cousin?
26. Describe a cricket.
27. What three kinds of crickets are there?
28. What difference is there between the house and field cricket?
29. What will crickets eat and drink?
30. Tell me how the cricket plays his tunes.
31. Tell me about the life of a field cricket.
32. Describe a mole cricket.
33. Describe a mole cricket’s nest.
34. Tell me something of the mole cricket’s habits.
35. What is it that makes the mole cricket shine sometimes?
36. Why has the mole cricket been called the earth crab?
37. In what is the mole cricket like a mole?
III.
1. To what order of insects do the frog-hoppers belong?
2. What can you tell me about insects of this order?
3. Will you mention some of them?
4. What can you say about their wings?
5. How does the little frog-hopper make the ball of foam?
6. Of what use to him is this ball of foam, or froth?
7. What does the scale bug make for his covering, instead of froth?
8. Which is the largest insect of this order?
9. What name has he besides cicada?
10. Which of the insects of this order is the ant’s cow?
11. Which one carries a light?
12. On what food do all hoppers feed?
13. Where does the cicada lay her eggs?
14. Why does she not put them in a living branch?
15. How does she make the hole in which to put her eggs?
16. Where do the larvæ of the cicada live?
17. What kind of weather does the cicada like?
IV.
1. To what insect order do moths and butterflies belong?
2. How do the feelers of butterflies differ from those of moths?
3. How does the butterfly hold its wings, while at rest?
4. Which side of the butterfly’s wings is more gayly colored?
5. Why is this?
6. How does the moth hold its wings while resting?
7. What are the butterfly’s wings often called?
8. Which has the thicker body, a butterfly or a moth?
9. Which has the more furry coat?
10. Which usually flies by night?
11. Do butterflies ever fly by night?
12. What is the food of these insects?
13. How do bees get honey from flowers?
14. How do they carry this tube when it is not in use?
15. Will you describe this tube?
16. What can you say of the butterfly’s legs and feet?
17. Will you describe the wings of a butterfly?
18. Why is the butterfly the best partner of the flower?
19. Why have butterflies been so much studied?
20. Where are the eggs of butterflies laid?
21. Tell me about butterfly eggs.
22. What is the creature called that comes from a butterfly’s egg?
23. Describe a caterpillar.
24. What is the first act of a caterpillar, after leaving the egg?
25. What does the caterpillar eat?
26. What can you tell me of the horns of the caterpillar of the
swallow-tail butterfly?
27. Why is this butterfly called by this name?
28. What is a girdle caterpillar?
29. How does the caterpillar pass into the pupa state?
30. What, then, is a caterpillar? (It is a butterfly larva.)
31. What effect has the weather on the pupa state?
32. Tell me how the butterfly leaves the pupa case.
33. How does a butterfly spend its time?
34. What does it do in bad weather?
35. Do any butterflies live over winter?
36. How do some caterpillars make a house for the winter?
37. Where is the silk-spinner of a caterpillar?
38. Why does a caterpillar make that sidewise motion with his head?
39. How do some caterpillars build a home for summer?
40. How do some spin or weave a hammock?
41. What can you tell me of the colors of butterflies?
42. Why are these insects called scale-winged insects?
43. What can you tell me of the hawk-moth?
44. In what is it like a humming-bird?
45. Why is one moth called a death’s-head moth?
46. Tell me about the wasp moth.
47. Where does it stay in the pupa state?
48. What is the bombyx?
49. Tell me all you can about the silk-worm.
50. Does the silk-worm moth ever eat?
51. Tell me about its caterpillar and its cocoon.
52. Which moth destroys furs and woollen goods?
53. Tell me about the tinea.
54. What can you tell me of the beauty of moths?
55. How can you capture moths to study or to keep?
V.
1. What is a bird?
2. How are eggs hatched?
3. On what plan is a bird built?
4. What can you say of a bird’s bones?
5. What can you tell me about a bird’s neck?
6. How do the bird’s bones help to keep it up in the air?
7. What shape is the breast-bone of flying birds?
8. What is the shape of the breast-bone of birds that do not fly?
9. In which part of the bird’s wing is the chief length?
10. Which is the short bone of the leg?
11. How many toes have most birds?
12. What is a bird’s beak?
13. Have birds any teeth?
14. What have they instead of teeth, for grinding their food?
15. What are a bird’s short feathers called?
16. Are any places on the body bare of feathers, and why?
17. What can you say of the large feathers?
18. Can birds move their feathers?
19. What else can you tell me about feathers?
20. Why do birds preen or dress their feathers?
21. What can you tell me about the feet of water birds?
22. What can you say about wading birds?
23. What kind of a bill has a duck?
24. How and why does it differ from a hen’s bill?
25. How are the beaks of fish-eating birds formed?
26. What can you learn of a bird’s habits from examining its feet and
beak?