Visible crew/equipment: When the policemen leaves with the girl, a crewmember's reflection is visible on their car. (00:04:15)
Continuity mistake: When the girl wakes up in the ambulance, she has much less dirt on her forehead for one shot. It reappears as she lays down. (00:09:00)
Visible crew/equipment: When the state policemen meet for the first time, the shadow of some equipment is seen on the wall behind them. It falls and you can even hear it. (00:17:30)
Continuity mistake: When Patricia is pouring formic acid in the glass, the nurse's hands change position on the girl's chair. (00:23:35)
Visible crew/equipment: When they find the giant nest in the desert, several parked cars and trucks are visible in the background. It is supposed to be an isolated place. (00:34:00)
Other mistake: When they encounter the first ant, the policeman runs out of ammo, but the FBI agent fires at least nine shots. Not bad for a snubnose revolver that holds 5 or 6 rounds.
Continuity mistake: When James Whitmore is attacked by the ant in the Los Angeles sewer system, James Arness arrives, firing an M-1 Garand rifle. In the next scene, he's armed with a Thompson submachine gun.
Revealing mistake: When Bob and Ben prepare to gas the ant nest, an ant appears below them. But its legs move too slowly, compared to the speed in which it appears; it rather looks like it is driving across the ground on (hidden) wheels.
Factual error: The crew gasses out the ant hill by dropping chemical grenades into the hole. But there are two reality mistakes about the grenades: 1) chemical grenades do not explode; they spray their contents into the area; and 2) considering the size of the ants, the size of their nest must be gigantic, and therefore, it would take more than a hundred grenades to flood it completely with cyanide gas.
Factual error: Grandpa Johnson's .30-30 Winchester rifle was apparently bent by the giant ants during their attack on his store. But as we can see later, the ants' mandibles are too thin and too curved to provide enough gripping and leverage area for bending a metal rifle barrel that severely.
Suggested correction: Impossible. When Ben Peterson is killed near the film's end, you can see that the ant's mandibles leave too much space even as they clamp shut. And their slender form is made for grabbing bites, not sturdy enough for crushing jobs.
That's just what I was talking about, if not quite correctly worded.
Revealing mistake: When the giant ants' nest is taken under fire with bazookas, it can be seen that the back-blast jets are just inserted, e.g. the 'zookas are not actually fired. Also, there is a cut between the 'firing and some of the explosions visible in the same frame.
Continuity mistake: When they go to visit the trailer, Pat is surprised by an ant on a bluff. When they shoot it, it falls with it's head just over the edge and two bushes in front of it. They switch to a camera angle from behind the ant and now its head is further back and there is a large white rock in front of the ant's head.
Factual error: In order to keep the giant ants inside the New Mexico nest, the protagonists bombard the entrance hole with phosphorus shells. Phosphorus burns at an average temperature of 5,000° Farenheit. At this temperature, the heat from the shells should have fused the sand around the entrance hole to glass (the threshold for this process is about 4,200° Farenheit), yet the sand remains unchanged.
Continuity mistake: When the police went into the trailer her did not have a pencil in his pocket, in the trailer bedroom he had a pencil in his shirt pocket to pick up the gun. Then in the next scene it is gone.
Continuity mistake: When the first officer is left alone at the store and hears the weird noise he shuts off the light. There is a different length of string than what was on it a second before.
Continuity mistake: When the two officers drive up to the first destroyed trailer the awning at the rear of the trailer is very visible. When the officer walks to the back of the trailer the awning is gone.
Character mistake: When the FBI agent (James Arness) is introduced to the chief the chief asks his if Ed has brought him up to date. The cop's name is Ben, Ed is the one who was killed.
Continuity mistake: Near the beginning, the two cops leave the trailer to go to Gramps' store. When they leave, the shadows are low but there should be plenty of daylight left. They arrive at the store and it's pitch black out, but it was only a twelve mile drive.
Factual error: When they put the pin on the map of Texas to mark the city of Brownsville, they are hundreds of miles off in West Texas near the city of Alpine. Happens around the time the patient who crashed the plane is interviewed in the hospital in Brownsville.
