The reason is, that they WOULD go with the lobsters to the dance.

'The reason is,' said the Gryphon, 'that they WOULD go with the lobsters to the dance. So they got thrown out to sea. So they had to fall a long way. So they got their tails fast in their mouths. So they couldn't get them out again. That's all.'
'Thank you,' said Alice, 'it's very interesting. I never knew so much about a whiting before.'
'I can tell you more than that, if you like,' said the Gryphon. 'Do you know why it's called a whiting?'
'I never thought about it,' said Alice. 'Why?'
'IT DOES THE BOOTS AND SHOES.' the Gryphon replied very solemnly.
Alice was thoroughly puzzled. 'Does the boots and shoes!' she repeated in a wondering tone.
'Why, what are YOUR shoes done with?' said the Gryphon. 'I mean, what makes them so shiny?'
Alice looked down at them, and considered a little before she gave her answer. 'They're done with blacking, I believe.'
'Boots and shoes under the sea,' the Gryphon went on in a deep voice, 'are done with a whiting. Now you know.'
'And what are they made of?' Alice asked in a tone of great curiosity.

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