Rupert and the Magic Shell

This is as close as I could come to reading one of the Rupert the Bear books. Rupert was created by Mary Tourtel in Great Britain for a newspaper, but he has gradually become a franchise.

This story takes Rupert to the beach where he hears of the plight of a merman through a magic shell.

One of the 1001 Children's Books (or, at least, I'm considering it as one, since I could never find one of Mary Tourtel's originals).