Ichthyomancy

Ichthyomancy is a method of Divination that relies on fish, either through the observation of the appearance and behaviour of fish, or through the inspection of fish entrails.

Praedico Predico, a shop in Diagon Alley, sold fish for ichthyomancy, as well as, presumably, other ichthyomancy apparatus.

Appearances

 * Harry Potter and the Philosopher's Stone