Continuity: When the men find the tracks of the dinosaur, the indent is flat and rounded, but when Frosty the poodle finds the dinosaur that made the tracks, its feet are skrawny and have pointy claws, which don't show up in the tracks.

Revealing: When the two dinosaurs are fighting besides the cliff, Malone and Jennifer Holmes hide behind a rock overlooking the cliff. One of the dinosaurs sweeps its tail, and knocks the two lovebirds over the cliff, but they fall onto a rock jutting out from the cliff. After we see them fall, there is a wide shot of the dinosaur swinging its tail. He swings it one way, then the other. After he swings it the first way, the tail freezes in mid-air for a split second, then swings the other way. It's obviously the same shot of the first tail swing, but played in reverse with a pause in between.

Revealing: When Gomez's partner is eaten, he is obviously a dummmy model, as his legs bend forward at the kneecaps.

Factual error: The dinosaur in the boiling water is carnivorous, and doesn't have that much trouble horking down part of the group - but it doesn't have any teeth to chew with.

Revealing: When the dinosaurs roll off of the cliff at the end of the fight scene, there's a closeup shot of Malone and Jennifer Holmes, and the dinosaur's tail as it falls. The problem is that it's obviously stock footage from the previous shot when the dinosaur's tail knocks Malone and Jennifer off of the cliff.

Revealing: When the two dinosaurs are fighting, they don't seem to be of any weight. They're banging against the ground, and none of the trees shake, and almost no sand is disturbed. Also there is no loud gutteral banging from them hitting the ground. There is no indication that they are any heavier than five pounds on a cheap miniature set.

Revealing: We all know that the dinosaurs FX in this movie are achieved by glueing horns, gills, and spikes to modern day lizards and reptiles, like baby alligators and the kinds you would buy at the pet store. But sometimes, it's too obvious. Especially in the fight between the two dinosaurs. The one sports a triceratops-like hood, which in real life was made out of a bony substance. But in the movie, it's wobbling like flimsy rubber.

Revealing: When Malone and the newspaper tycoon's daughter are running from the dinosaur, when the film shows both the dinosaur and the two people in the same shot, one of them changes color, due to bad matting effects.

Character mistake: At the end, Professor Challenger misidentifies the dinosaur in the boiling water as a T-Rex. Its arms are too long, and it sports horns. It is much more likely a carnotaur. This area being a forte of his, I doubt Professer Challenger would make this mistake.

Audio problem: When Malone and Roxton are fighting, Roxton hits Malone's hand, but we hear the sound effect used for a punch to the face.

Continuity: The plateau is much bigger in the ground shots than in the arial shots.

Revealing: Whenever the dinosaurs are seen walking on dirt or sand, if you look closely, you can see individual grains of sand and small clumps of dirt. This would not be possible, unless the "dinosaur" was a foot and a half long at the most.

Revealing: During the fight between the two dinosaurs, one of the dinosaurs swings its tail, knocking Jennifer Holmes and Malone over the cliff, then there's a wide shot of its tail swinging. The trouble is that when the tail hits the two lovebirds, it changes color from the wide shot due to bad matting effects.

Visible crew/equipment: The string holding up the "Fire Monster" to make it appear like it's standing upright is seen in a couple of shots.

Deliberate "mistake": In real life, the Brazilian natives do not wear clothes at all except for speedo type shorts, even the women. This is a deliberate error to keep the film "clean."

Factual error: When Summerlee drops the egg, we see it break. When it splits open, there's no yolk for the baby dino to eat while he's in there and there's no fluid for the tike to swim around in. It looks like they just shoved the lizard into an egg model and threw it on the ground.

Revealing: The group closes a rock door to escape from the native Indians, but you don't even have to look closely to see the rock door is paper mache.

Factual error: The plateau blows up because of a volcanic explosion, but the explosion looks nothing like a real eruption. First of all, the plume would be a darker colour, mostly dark grey, and second, the explosion would fly out of the tube the group came out of, so they should still be running, not resting. Also, there would be danger from pyroclastic flow, and lava runoff.

Continuity: When the group finds the dinosaur tracks, Frosty the poodle runs away and finds said dinosaur, but the size of the tracks the men find and the size of the dinosaur don't match.

Revealing: When Frosty the poodle finds the first dinosaur, we can see that one of the horns he sports is crooked. Um, this didn't happen in real life.