The Raccoons, Season 3 (1988)

Ralph:
Bert's certainly gone a bit overboard on the story about Sir Malcolm. It reads like one of his books; good story, but very few facts.

Cedric:
What do you mean Ralph?

Ralph:
Well, I've tried supporting evidence for some of Sir Malcolm's claims, but there's just no proof.

Cedric:
And some of the places he talks about aren't even on the map.

Bert:
Of course they're not on the maps! They're lost cities Cedric!