The mounted head of a Moosephant.
Moosephant is the nickname for an endangered or extinct species of animal, roughly a cross between an elephant and a moose. These creatures are perpetually surprised at their own existence. Mortimer von Fogwhistle killed one of the last five and mounted it on his wall, and it became a Ghost. (Mark III: "Ghosts!")
Moosephant are considered a type of Pokémon and can be caught as one in the Pokemon universe. Gash Ketchum caught one. (“Pokémon Stop”)