This specimen was sent to Othniel Charles Marsh, who believed that the formation from which it came dated from the Pliocene, and that the bones belonged to a particularly large and unusual bison, which he named "Bison alticornis".
Njegovim ugotovitvam sta oporekala paleontologa John Ostrom in kasneje David Norman, ki sta oba uvrstila "Triceratops" v poddružino Centrosaurinae.