When the pilot is trying to land at LAX, he is flying in rough weather with no visibility. Exterior shots of the ground below show a calm, cloudless sky.
When the group enters the TV studio, Cal's rifle is slung over his arm as they close the doors. When they finally close the second door and move into the studio, his rifle is gone. When they finally get inside and Cal introduces himself, his rifle is suddenly on his shoulder again.
When Lisa goes into the fog to search for Tom and the professor, she leaves her purse in the car. When she re-emerges, her purse is in her right hand.
When the Professor and his daughters pick up Tom, interior shots of them driving have completely blacked out windows rather than a daylight road scene.
When Cal and the Professor are in their newly acquired black Cadillac, the wide interior shots show a white car. The car is rocking back and forth, but the view through the windows shows that the car is not moving.
At 1:04:07 Tom has regained the rifle he left in the cave earlier while fighting with one of the Slime People.
In his interview, Dr. Brough, who has "seen the creatures", describes them as "large, huge, prehistoric." They are barely as tall as the leading man.
During the TV interview, Dr Brough flubs his line, "to sheik, seek shelter"
During their initial scene together, in Dr. Galbraith's station wagon, Robert Hutton speaks over Judee Morton's line, starting "And, uh," before she has finished her line "and us."