c.o.c.kroaches may not be pleasant, but who can say they are not interesting?
What other insect lays its eggs in little bandboxes?
Here is one of the little boxes, shiny and hard.
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This little case is at first a sticky substance that soon hardens. The eggs lie in it side by side in two rows.
These cases remain attached to the abdomen of the female c.o.c.kroach until the eggs are all laid. Then the case falls off, and soon out runs a crowd of infant c.o.c.kroaches.
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The case is something like a satchel that shuts with a spring. The youngsters are packed close together, side by side, with their heads towards the mouth of the satchel.
As soon as one hatches it pushes open the side of the case and creeps out. Then the case springs together again to protect the rest of the brood.
They are funny fellows when they first come out, little and white-looking. But they eat and grow of course, and shed their skins, and after each moult they become darker in color.
Now, do look again at this c.o.c.kroach I have taken such pains to catch for you and put into the tumbler.
I think even May will own that it has a cunning little head.
See it turn its head around to look at us.
After all, the c.o.c.kroach is a knowing little fellow.
This one is hungry; it has had nothing to eat for some time. We will give it this crumb of cake.
Be careful, or it will get away; it can run very fast, and it is very quick, you see, in all its motions.
Ah, it is examining the crumb with the tips of its long antennae.
See how daintily it touches the crumb.
It can smell with its antennae, you know.
Now it has decided the cake is good to eat.
See how eager it is!
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It almost stands on its head to reach just the part it wants.
John says he does not understand how insects smell with their antennae.
I can tell you a little about it, John.
If you look at one of the c.o.c.kroach"s antennae under the magnifying gla.s.s, you will see it is made up of a good many short pieces, or segments, as we call them, fastened together end to end.
Yes, Mollie, that is why it can move about so easily. It can curl up like a whiplash, you see.
Next the head is a round segment that fits into a socket.
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Double up your right fist and fit it into the half-closed palm of your left hand.
There! That is like the ball-and-socket joint.
You see you can move your fist around in all directions.
The insect can move its antennae in all directions because they are fastened to its head by ball-and-socket joints.
On the segments of the antennae, particularly towards the tip, are little dots.
You cannot see the dots without the help of a strong microscope, but they are there.
These little dots are sensitive spots. There is a nerve coming from the insect"s brain to each dot.
Some of the dots are sensitive to odors, just as the nerves of our nose are sensitive to odors.
May thinks it is very funny that the insects smell with antennae instead of with noses.
The insects, no doubt, would think it very funny for us to smell with, noses instead of with antennae, if they thought about it at all.
The little dots on the antennae are extremely sensitive to smells. They are often much more sensitive than our noses.
Put a bit of food at some distance from a hungry c.o.c.kroach, and it will not be long before a pair of long, sensitive feelers will come waving to and fro out of some dark corner.
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Little Mrs. c.o.c.kroach has smelled the dainty morsel, and, as soon as it is dark, out she will run, her feelers moving eagerly this way and that, until she has found it.
Yes, May, insects also feel with their antennae. That is why the antennae are often called "feelers."
There are other dots on the segments that are sensitive to touch.
Sometimes there are tiny hairs on the antennae, also sensitive to touch.
The little fellows feel and smell, yes, and oftentimes _hear_ with their antennae.
Many insects have spots sensitive to sound on the antennae.
Yes, indeed, May, it is wonderful that such tiny threads as an insect"s antennae should hold so many kinds of sensitive spots.
An insect"s antennae are among the most wonderful things in the world.
And _I_ think a c.o.c.kroach, in spite of its bad reputation, is a very wonderful little fellow.