Another funny Crab is the Spider Crab. Its back is covered with reddish
bristles, like so many hooks. These catch in the seaweed, and soon the
Spider Crab is decorated with bits of weed. But that is not all. The
artful Crab tears off other pieces of weed with its pincers, and
attaches them to the hooks. It is another dodge, of course, to escape
from enemies. The Lobster, whose picture you see, has a life-story much
like that of the Crab. He, also, grows too big for his suit of armour,
and casts it off in a wonderful manner, but only after a great deal of
trouble. In his new suit he is very weak and soft--an easy prey to the
first enemy to find him. He cannot defend himself then; he can only lie
helplessly on his side, waiting for his coat to harden. He is so weak
that his soft legs cannot bear the weight of his body.

[Illustration: HERMIT CRABS FIGHTING.]

Needless to say, the Lobster always finds a secure retreat before
casting off his protecting coat of armour. A hole under a rock suits him
well at that time. Strange to say, he seems to dislike his old clothes,
and often crunches them to pieces or eats them up, or even pushes them
under the sand or stones! Then he marches out like a proud warrior,
knowing his strength, and the power of his great claws.

Lobsters are fond of fighting, and must be very disagreeable neighbours.
They can swim along by using the little "swimmerets" under their bodies.
Or, by rapidly bending down their powerful tails, Lobsters are able to
shoot backwards through the water at a great pace. In our next lesson we
shall find that Prawns are also able to paddle forwards or dart
backwards in a similar way.