How often does Mr. Crab get a new coat? His coat does not wear out. But it gets too small. Then he changes it to get a larger one.
The baby grows fast. You seem to see it grow.
You grow fast. They say it is hard to keep you in clothes. You cannot wear the coat you had last year. But your papa can wear his coat for many years. He will tell you that he is done growing.
It is so with a crab.
When he is very young, he grows fast. He needs a new shell very often.
When he is older, he grows more slowly. Then he gets a new coat every spring.
At last he does not grow any more. He keeps the same shell, year after year.
It gets very hard and thick, and loses its bright color. Very often it is nearly covered with limpets.
They fasten their flat or pointed shells to the crab’s back, and stay there. I cannot tell you just how long a crab lives.
Of what use is a crab? Have all things a use?
Sometimes we cannot find out the use. Crabs are good for food.
Some kinds are eaten by men, as fish and oysters are eaten. Birds eat a great many crabs.
Some birds almost live on them. Fish eat many crabs.
There are many kinds of crabs so small that you could hardly see them. Fish feed on them.
Men catch and eat the fish. Crabs help to keep the sea and the sea-shore clean.
Crabs are greedy. They eat nearly all kinds of dead things that would spoil and make a bad smell if left on the sand.
They eat dead fish, dead animals that are thrown into the sea, and grubs, flies, and worms. Do you ever see men going about to clean the streets?
The crabs help to keep clean the sea and the shore. There are so many crabs, and they eat so much, and so fast, that they can clean away much of the dead stuff that lies on the shore.