After he falls off a pier at Coney Island (loving the fake, Hollywood 1964 version of a 1940s era subway ride!), his body is never recovered (because he turned into a fish) and he's presumed dead. His obituary reveals that he resided at "1313 Pleasant Avenue, Flatbush," a non-existent street in Brooklyn.
But when he first meets his friend Crusty, the hermit crab:
Crusty: Say, what are you, anyway? You related to the porpoise family?Oh proud Flatbushian, Henry Limpet, laying claim to all of Brooklyn, we salute you!
Henry: No, I'm a Limpet. Henry Limpet from Brooklyn. You know, Flatbush.
Crusty goes on to call him "Flatbush" for the rest of the film.
This was one of my favorite childhood films. Of course, I identified with Don Knotts' character, a bookish, withdrawn person who identified more with the animal world than his human clan. In particular, I lived in Florida at the time and loved fish and all things aquatic. Later, during my adolescence, I maintained several aquariums; I wept when my pet Oscar jumped out of the tank for the last time. When I was 12 years old, my answer to "What do you want to be when you grow up?" was "either a marine biologist or a neuro-surgeon." Needless to say, I'm neither, today, but the interests remain.