It is based on the Rite of Spring segment of the 1940 Disney animated feature film Fantasia.
In Disneyland, it comes immediately after the Grand Canyon between the Tomorrowland and Main Street stations. In Tokyo Disneyland, it is located in a mining shaft behind Big Thunder Mountain Railroad, heralded by a Triceratops skeleton at the entrance to the tunnel.
At the Primeval World, guests see a number of dinosaurs in a supposed natural habitat after traveling back in time.
Dinosaurs and other Prehistoric Animals
Edaphosaurus - Actually a reptile that died out before the dinosaurs existed, though this is a common mistake. They are among the first creatures shown, and have characteristic glowing red eyes.
As with many of the dinosaur-based items in the world, it depicts dinosaurs from all different time periods and places in the same habitat. This is also seen in the film The Land Before Time, and Dink, The Little Dinosaur which is non-Disney.
Many of the dinosaurs are out of proportion to their actual size.
The Brontosaurus are seen chewing plants like cows. This is known to be incorrect, as they swallowed their food whole and it was broken down by gizzard stones (gastroliths)
The Brontosaurus also had nostrils on their nose instead of the top of their head.
Brontosaurus had spines.
Brontosaurus did not drag its tail on the ground.
Stegosaurus's tail should be more elevated and have only four spikes instead of five.
Struthiomimus had feathers.
Pteranodon is shown standing on its hind legs, when it should be on all fours with its wings folded like a vampire bat.
Pteranodon like all pterosaurs also had fur and lacked bat wings.
Edaphosaurus went extinct before the dinosaurs existed, and it should have naked mammal-like skin instead of scales.
The Tyrannosaurus rex near the end has a number of anatomical faults: