Blue Ridge Mountains, Georgia.
Heuvelman's Lake is actually named after Belgian cryptozoologist Bernard Heuvelmans who wrote the massive volume "In the wake of the Sea Serpents"
This episode is one of the few notable episodes in which the story line does not deal with any paranormal or supernatural forces.
The teenagers featured licking the toad in the scene on the dock appeared earlier in the season in the episode "War of the Coprophages."
In Heuvelmans Lake appears on souvenir mugs in The X-Files: The Game.
Scully: You know, Mulder, you are Ahab.
Mulder: You know, its interesting you should say that, because I've always wanted a peg leg. It's a boyhood thing I never grew out of. I'm not being flippant; I've given this a lot of thought. I mean, if you have a peg leg or hooks for hands then maybe it's enough to simply keep on living. You know, bravely facing life with your disability. But without these things you're actually meant to make something of your life, achieve something earn a raise, wear a necktie. So if anything I'm actually the antithesis of Ahab, because if I did have a peg leg I'd quite possibly be more happy and more content not to be chasing after these creatures of the unknown.
Scully: And that's not flippant?
Mulder: No. Flippant is my favourite line from Moby Dick. Hell is an idea first born on an undigested apple dumpling. Yeah.
(Scully smiles, finishing the line with Mulder)
Scully: What was that?
Mulder: I don't know, but it ain't no duck.
(Scully's dog starts barking in the back seat)
Scully: Nature's calling, I think we should pull over.
Mulder: Did you really have to bring that thing?
Scully: You wake me up on a Saturday morning, tell me to be ready in five minutes, my mother is out of town, all of the dog sitters are booked and you know how I feel about kennels. So, unless you want to lose your security deposit on the car, I suggest you pull over.
Scully: They're fictional creatures, Mulder. Folktales born out of some collective fear of the unknown.
Mulder: A folktale that quite possibly ate a biologist and a Boy Scout leader.
Mulder: Hey Scully, do you think you could ever cannibalize someone? I mean if you really had to.
Scully: Well, as much as the very idea is abhorrent to me, I suppose under certain conditions a living entity is practically conditioned to perform whatever extreme measures are necessary to ensure its survival. I suppose I'm no different.
Mulder: You've lost some weight recently, haven't you?
Scully: Yes, yes I have. Thanks for n-- (Scully glares at Mulder and he laughs)
Scully: We eat fish and fish eat us.
Mulder: Are fish also known for eating half and saving half for later?
Scully: What was that?
Mulder: It ain't no bass...
Scully: You know in the old mariners maps the cartographers would designate uncharted territories by writing "Here be monsters"
Mulder: Well I got a map of New York City just like that.
Scully: You're so consumed by your personal vengeance against life, whether it be its inherent cruelties or mysteries, everything takes on a warped significance to fit your megalomaniacal cosmology.
Mulder: Scully, are you coming on to me?
The boat that sinks out from under Mulder and Scully is the Patricia Rae, named after writer Kim Newton's mother.
Tyler Labine and Nicole Parker return as Stoner and Chick. They first appeared in "War of the Coprophages".
Mulder's speech about wanting a wooden leg in order to justify not having to work so hard in life comes straight out of Berne's pop psychology bible "Games People Play".
Millikan County is named after Rick Millikan, a casting director for the show.
Most of the third act (know to most X-Philes as the Conversation on the Rock) was written by none other than an uncredited Darin Morgan ("Humbug", "Clyde Bruckman's Final Repose", "War of the Copropahges", "Jose Chung's 'From Outer Space'"), his last writing job for the show.
Scully obtained Queequeg after the dog's former owner died in "Clyde Bruckman's Final Repose", in which the little beast dines on the old lady's entrails. Queequeg also makes a screen appearance in "War Of The Coprophages", getting and escaping from the midst of a flea bath.
Scully's dog is named Queequeg after the harpoonist in "Moby Dick", a story her father read to her when she was growing up. Their nicknames for each other (Ahab and Starbuck) come from the same book.
Episode Title: Quagmire
A quagmire is described as a soft wet area of low-lying land that sinks underfoot. This would describe the surrounding area where 'Big Blue' was believed to be.