A complete mosasaur skeleton, osseous and cartilaginous - 1899
Fossil mammals of the Tertiary of northeastern Colorado: Ameican Museum collection of 1898 - 1901
The reptilian subclasses Diapsida and Synapsida and the early history of the Diaptosauria - 1903
The osteology of Champsosaurus Cope - 1905
The Carnivora and Insectivora of the Bridger Basin, middle Eocene - 1909
Integument of the iguanodont dinosaur Trachodon - 1912
Crania of Tyrannosaurus and Allosaurus - 1912
Equidae of the Oligocene, Miocene, and Pliocene of North America, iconographic type revision - 1918
On the structure and relationships of Notharctus, an American Eocene primate - 1920
<i>Camarasaurus, Amphicoelias</i>, and other sauropods of Cope - 1921