At the urging of paleontologist Henry Fairfield Osborn, American paleoartist Charles R. Knight consulted with Edward Drinker Cope in person in early 1897 about a set of illustrations of prehistoric reptiles, one of Cope's specialties. Shortly after, Knight reconstructed "Edaphosaurus" (as ""Naosaurus"") with a "Dimetrodon" skull that Cope had previously referred to that genus in error. This painting was commissioned for the American Museum of Natural History in 1897 and was reprinted for Cope's obituary in the November 1898 issue of "The Century Magazine". Knight later created a more accurate revised version of the painting that turned ""Naosaurus"" into "Dimetrodon", with a corrected head and teeth, and a sail with smooth, unbarred spines. He also turned the "Dimetrodon" in the original background into "Edaphosaurus" (still called ""Naosaurus"" at the time) with a different head and a sail with crossbars.