This showed that the Wise Old Crayfish had been well brought up, and knew he should not say unpleasant things about people if he could help it. When there was need of it, he could tell unpleasant truths, and indeed that very evening he did say what he thought of the Eels. That was when he was teaching some young Crayfishes, his pupils. Their mother had brought up a large family, and was not strong. She had just cast the shell which she had worn for a year, and now she was weak and helpless until the new one should harden on her. "It is such a bother," she said, "to keep changing one's shell in this way, but it is a comfort to think that the new one will last a year when I do get it."