Dr. Laird installs a fence of corrugated iron around his home as a shield against the magnetic forces he is producing, but the exterior shot of the house in the final scene shows no fence.
When Gil Graham (Forrest Tucker) and Jimmy rescue the new school teacher from the giant insects, they learn that Michele (Gaby André) is in danger outside. Graham goes running out of the building, but when the camera shows the outside of the school, it is obviously not Forrest Tucker, but a stand-in that is running out.
When the soldiers fire their rifles, the sound-effect includes the 'zing' of a ricochet rather then simply the 'crack' of a rifle shot.
Michelle gets stuck in a web and is menaced by a giant spider, which is hanging from a tree behind her, but when she is rescued the tree has transformed, into a white painted wall suitable for front projection.
Dr. Laird installs a fence of corrugated iron around his home as a shield against the magnetic forces he is producing, but the exterior shot of the house in the final scene shows no fence.
When the bugs are banging at the schoolhouse door, the top moves in and out, suggesting that there is no pin in the upper hinge.