Dinosaur Bone
“Enormous, carnivorous, and psychically mutated, one thing for sure you can say about the valley's prehistoric inhabitants: we are glad they're dead. Nobody wants to see levitating Velociraptors. SCARY.”
The Dinosaur Bone is a Scavenger Hunt item located in the Reception Area in Psychonauts, in the top branches of the dead black tree near Janitor Cruller's trailer. Levitation is required to reach it.
Although the description mentions dinosaurs being psychically mutated, the Psitanium meteorite had not yet crashed when dinosaurs existed, if the tree stump timeline in the parking lot is to be believed. It is possible that this is more of a hypothetical statement, noting that if the dinosaurs were still around, they would have had even more fearsome abilities due to the Psitanium.