Continuity mistake: After the villain (Thayer David) kills a duck, a boulder begins to move and brushes the side of his right leg as seen in a close-up and both legs can squarely be seen as he is standing beside the rock. The scene changes to a stunt-man who has his left-side towards the camera and this time his right leg is closer to the boulder which pushes him over a ledge.
Continuity mistake: James Mason meets the villain (Thayer David) who holds a gun on Mason and the rest. Mason outwits him by throwing salt into his face to blind him. When the salt hits his face, he closes his eyes (too early) before impact. The salt impact hits the right side of his face. An angle change occurs and we see a close-up of him (or a stunt double - his hair is different) and the salt hits the actor squarely in his face with his eyes open to the last microsecond. The scene changes back to show Mason and the villain with the salt on the right-side of the villain's face again with him in agony.
Continuity mistake: When they are climbing up out of the hole to avoid the rising water in the cave, as they show the hole from below the water is about two feet below the hole, however when shown from the top the water looks to be about six inches below the hole, this keeps shifting back and forth during that scene.
Continuity mistake: Arlene Dahl trips while running away from a dinosaur by stepping into a loop in a rope attached to a raft. Her foot snags it below the ankle near her toes. A few seconds later, you see a close-up of her and the dinosaur and now the rope is above her ankle. A few scenes later it's below her ankle again as the men come to her rescue.