But frogs can.
A frog will try to swallow almost anything it can catch, and it watches
for the dragon flies when they come to lay their eggs in the water.
Suddenly it jumps out, and away goes poor dragon fly into that great
wide frog-mouth.
[Illustration]
Now look at the legs of the dragon fly. It has six.
Every dragon fly has six legs.
They are rather short and small for so large an insect, but that is
because it does not need large, strong legs.
You never saw a dragon fly dig a hole, or run, or even walk, did you?
Their legs are not arranged for walking. All six of them are directed
forwards as though they were reaching out after something. And so they
are--reaching out after insects.
Dragon fly catches his prey while he is flying, and he grasps the
insects with his feet.
He snatches one, and then what?
Does he sit down somewhere and eat it?
Not he, he is far too hungry for that; he continues his swift flight,
and as he flies he eats.
As soon as he has finished one fly or gnat, zip! he snatches another.
He has an insatiable appetite, consuming hundreds of insects in the
course of a day. Nor does he confine his attention to flies and gnats
and mosquitoes and such small fry. He catches what he can. A large
dragon fly will even gorge himself on one of the large-sized
butterflies, and one has been seen calmly chewing away at an enormous
wasp!
No, indeed, Mabel, the dragon fly does not eat the wings of the
butterfly, it eats only the soft body.
Probably nothing eats a butterfly, wings and all. Birds and insects
sometimes catch butterflies, and you often see the bright wings lying on
the ground. The wings of insects are not worth eating, and are almost
always cast aside by the creatures that eat the insects.
Besides catching insects with their legs, the dragon flies cling fast to
things with them, but when they wish to move they do not walk, they fly.
Yes, indeed, Frank, you are right; their legs are jointed.
That is so they can move them easily and fold them up when they want
to.
They would find it as hard to get along without joints to their legs as
we should.
Wouldn't we be stiff if we had no joints!
See, the legs and wings are fastened to the middle part of the body, the
_thorax_, we call it.
All insects have the legs and wings attached to the thorax.
The rest of the body is the abdomen. See how long it is.
[Illustration]
It is the long abdomen that gives the dragon fly its name of spindle, I
suppose.
The abdomen is jointed, and it can curl up.
All grown-up insects have a head, a thorax, and a jointed abdomen.
* * * * *
What are you looking at, Charlie?
Something moving in the bottom of the pond?
Let us get it out.
Here, we will dip it out with this cup.
What a lot of stuff!
Sticks and mud--and--what is that?
Something alive, surely.
Let us put some clean water in the cup and examine what we have found.
My! my! what a queer little thing!
What do you suppose it is?
Ah, I know now, but I do not think you could ever, ever guess, not if
you tried a week.
It is a young dragon fly!
It does not look much like its shiny-winged parents.
It looks like I don't know what, with a face like--well, when you look
right in front of it, like a pug dog.
Queer! Well, I should think so! What is that, Amy? Am I sure it is a
dragon fly?
Yes, there is no mistake; a dragon fly one day dropped an egg in the
pond, and out of it hatched--this.
[Illustration]
It will some day become a shiny-winged dragon fly and catch mosquitoes.
We will call it larva, and we will watch it a little while.
Look and see if it has a head, a thorax, and an abdomen.
Are there antennæ on its head? And has it eyes?
If you were to look at its eyes with a microscope, you would find that
they are made of six-sided facets, like the eyes of the grown-up dragon
fly.
They are compound eyes, but they are not as large as the eyes of the
grown-up dragon fly.
How many legs has it? What are its legs fastened to?
Yes, Nellie, thorax is right.
Its six legs are fastened to its thorax. I am glad you remembered
thorax.
Has it a jointed abdomen? and has it wings?
Look! did you see that?
It opened its innocent-looking face all of a sudden, just darted it out
into a long-handled spoon, with hooks at the end, and hooked up that
little grub.
Now it is holding the grub on the hooks in front of its mouth and eating
it as greedily as if it were half starved.
[Illustration]
So that is why its face looks so queer.
It is its long under lip all folded up in front like a mask that makes
it look like a pug dog.
When it pleases it darts out that lip, and any unlucky insect or snail
may fall a prey to its greedy appetite.
It is said that the larvæ of some dragon flies even eat pollywogs and
small fishes.