Other mistake: According to the plot, no life is possible in the Northern Hemisphere by the time the film is set. Yet, when the sailor who has been sent ashore to look around the San Diego refinery enters the premises (more precisely, when we see the smoking-prohibited sign on our right and his left) a bird can be seen flying in the upper left-hand corner of the screen.
Other mistake: The exhaust of the space ship is so strong that it knocks down Jeff and Paula to the ground, but their hair doesn't get changed at all.
Other mistake: When the three fairies are cleaning up the cottage, Merriwether has the broom magically sweep all the dust into a pile, then she makes the pile disappear. Right after it does so, the picture is stuck in a freeze-frame for about half a second.
Other mistake: Mick the orderly is Irish throughout the film, but when Nurse Dawson bumps into him and says, "You clumsy oaf," Mick's reply, "Look who's talking," is said in a London accent.
Other mistake: The second bus in the scene before the crop duster has no license plate.
Other mistake: When Lance leaves Nora to go have a meeting with the remaining people in the house and they accuse Loren of murder, his room is locked from the inside but when he returns he opens the door without any trouble.
Other mistake: When Sugar and Josephine are talking on the telephone, Sugar's eyes are moving backwards and forwards, obviously reading from a cue-card.
Other mistake: When Anne and Peter are looking at the stars, Anne points to a star and Peter knows what star she's pointing to. It is impossible to point to a star and have someone else know exactly what star you're pointing to. Try it.
Other mistake: Close to when Tony Curtis and the nurse are going back to the pink sub, there is one scene where in the far background there are two objects moving on the water each creating a wake. It looks like someone is water skiing. A DVD will likely show this clearer.
Other mistake: When the Behemoth swims up the river & capsizes the ferry, a static model is used that bears no resemblance to the animation model seen throughout the film.
Other mistake: When Joe shoots the person at the beginning of the movie the character is played by Bing Russell (Kurt's father). Later in the movie when Dude is ambushed at the entrance to the town, they give a guy his hat to impersonate Dude - it's Bing Russell again, after he was killed off at the beginning and why Joe is arrested in the first place.
Suggested correction: The actor in that scene is not Bing Russell.
Other mistake: If it was a party line why did Tony Randall get a busy signal when he was calling Doris Day from Rock Hudson's apartment?
Suggested correction: Dialing the number from a party line would get you a busy signal. If you wish to dial the other party you would dial a special code. In the movie it is 793.
Other mistake: The Count and the Professor jump into the water to save themselves from the dinosaurs (which can't swim). In the long shots, it appears they are out very far, in at least six foot deep water, but close up, the water they are in couldn't be higher than four feet. What's to keep the dinosaurs from grabbing the two if they're in water that wouldn' come up to the dinosaurs' kneecaps?
Other mistake: A Telechron electric clock on the fireplace mantel keeps time even though the power has failed.
Other mistake: A police officer fires two shots, hitting a bank robber in the back. The "bullets" do not make holes in the robber's coat. All they do is create two tiny puffs of dust.
Other mistake: After the intro, one girl in the bar peeks from the window and goes; "Say, here comes Gordy and Jennie." And indeed the duo is getting off the car and joins them. The problem is, the window is on the opposite side of the entrance and there's diegetic music playing throughout the scene. In other words, she saw them parking to the left, but in a split second they are coming through a door on the right. (00:02:40)