Triceratops was one of the most common dinosaurs at the end of the Cretaceous Period. Its most prominent features are on its head: two long brow horns, a nasal horn, and a bony frill. Its frill had no ...

Image credit: (above) Struthiomimus and Triceratops, Douglas Henderson, pastel on paper, 1999. From the children's book, Asteroid Impact, 2000.