Other mistake: Mary Ann comes up to the Skipper while he's learning to juggle. If you look closely, the coconut bounces on the ground a couple of inches from his left foot. When Gilligan approaches, the coconut bounces off the bottom shelf. And in both times, the Skipper reacted in pain.
Other mistake: When Mrs. Howell looks at the lion in the mirror, the image is not reversed as it should be when the camera looks directly at the lion.
Chosen answer: It looks like a mistake to me I see it when the Professor is put into a trance, but it is not there later.
Bowling255 ★