It wriggles out of its old skin as though it were an old coat, and
leaves it clinging to the weeds in the pond.
Sometime you may find these cast-off dragon fly overcoats.
After it has shed its skin the dragon fly continues to grow. It keeps on
growing until it has outgrown its new skin.
Then what do you think it does?
Yes, Charlie, that is right, it sheds this skin too.
[Illustration]
When it sheds its skin we say it moults.
It moults several times, and at last little short wings appear. At first
it has no wings at all, you know.
Amy wonders how the larva breathes under water.
Ah, Master Ned, you are laughing too soon. You think insects do not have
to breathe, but you are very much mistaken, sir.
Insects do have to breathe.
They would die if they could get no air to breathe.
Some of the dragon fly larvae have an odd arrangement for breathing under
water. They have a sort of syringe in the end of the body, and there are
breathing pores or gills in the syringe.
The water goes in and out of this syringe, and the larva breathes as the
fish does, by means of its gills.
Yes, May, its gills are in its syringe, which seems very odd,--you see
the dragon fly larva breathes at its tail end instead of at its head
end.
Mollie thinks it is an upside-down, inside-out sort of a creature
anyway. But it knows what it is about.
Ned wants to know how it can get any air to breathe when it lives under
water.
The truth is, there is always air mixed in with water, and it is this
air the larva breathes when the water goes in and out of the syringe.
It uses the syringe for another purpose too. When it pleases it can
shoot out the water with great force, and thus propel itself quite a
distance.
By means of the syringe it can leap through the water faster than it can
move by its slow-going legs.
Mollie wants to know if we can see the syringe.
No, it is inside the body.
But there is a kind of dragon fly that has a pair of gills outside, at
the end of the abdomen, instead of the syringe inside.
The best I can do is to show you a picture of one. Some day we may find
it in the pond.
[Illustration]
Those two feather-like parts at the tail end are gills.
Yes, John, it can propel itself through the water by rowing, as it were,
with these gills.
There are some species of dragon fly larvae that swim by moving the tip
of the abdomen from side to side, as a fish moves its body when it
swims.
But now let us return to our funny larva that lives at the bottom of the
pond. It stays down there, eating and growing and moulting, for nine or
ten months or even longer; then something very wonderful happens.
It suddenly feels a great desire to get up to the top of the pond.
[Illustration]
It climbs up a weed or a stick until it is clear out of the water.
Then its skin splits down the back for the last time, and out there
pulls itself, not a larva, but a weak-looking dragon fly, with soft and
flabby little wings.
Public-domain text, read in full here on John Shaqi.
Reviews
Reviews
No reviews yet
Be the first to share your thoughts on this work.
Join the Discussion
Join the discussion
Sign in to leave a comment or review.
Sign InorCreate an account