The Beast Of Hollow Mountain is a natural and presumably adolescent Allosaurus. It made its appearance in the 1956 B-movie of the same name. In the film, this prehistoric predator lives in the cave of Hollow Mountain, located in the back-country of Mexico. This monster is distinguished from other allosaurs by its abnormally long tongue.
The Beast Of Hollow Mountain is 20 feet long weighs 10 tons. One interesting thing to note is that while this dinosaur is generally regarded as a tyrannosaurid, it has 3 fingers on each hand, bearing a similarity to the Allosaurids, even though so there have been finds of Tyrannosauroids that measure around this size.