In Fish Licence, what kind of fish is Eric?

In Fish Licence, Eric is a halibut.

The sketch follows Eric Praline, played by John Cleese, as he visits a post office to obtain a licence for his pet fish, also named Eric. When the clerk questions the request, Praline repeatedly insists that his fish is a halibut. The fish's flat shape becomes the basis for another joke: Praline says he chose Eric from thousands because the others were “too flat.”

The clerk calls Praline a “loony,” prompting an increasingly elaborate defence involving supposedly famous people with unusual pets. The routine eventually expands into a dispute over dog, cat, and fish licences before the Lord Mayor appears with an official statement.

Fish Licence first aired in the second series episode “Scott of the Antarctic” on 1 December 1970. An album version leads into “Eric the Half-a-Bee,” but that song is not part of the original television sketch. The fish is specifically a halibut, not a cod, trout, or haddock.