Protoceratops

The Protoceratops were a type of dinosaur which existed around 100 million years before the 20th century.

The creature was "ust over two metres" long. It had a parrot-like beak and a bony shield growing over its face and extending backwards to cover the neck. The Fourth Doctor once landed in the middle of a Protoceratops nest and began examining the eggs, joking about broiling one and eating it for breakfast. His interference with her nest riled up a Protoceratops mother and he had to retreat to the TARDIS in a hurry. (PROSE: The Doctor Who Dinosaur Book)

Whilst looking for Ace in Cretaceous Mongolia, the Seventh Doctor saw a protoceratops. (PROSE: Living in the Past)

Protoceratops were one of the creatures that the Silurians bought back from extinction. They were allowed to roam free and used for food. (PROSE: Blood Heat)