In 1842, Sir Richard Owen created the name Dinosauria. In the same publication, he attempted to redescribe Riley and Stutchbury's "Paleosaurus" and "Thecodontosaurus", which he did not consider to be dinosaurs. Not knowing of the change in spelling, he changed the name back to "Palaeosaurus", and this spelling was followed by all subsequent authors until 1959. Owen assigns other bones to "Palaeosaurus", which would later be re-classified to the prosauropod dinosaur "Thecodontosaurus". Contrary to Owen, in 1870, Thomas Henry Huxley described both "Thecodontosaurus" and "Palaeosaurus" as dinosaurs for the first time. He considered "Palaeosaurus platyodon" to be synonymous with "Thecodontosaurus antiquus", most likely due to the "Thecodontosaurus" bones that Owen assigned to the former genus. However, Huxley regarded "P. cylindrodon" as an unrelated carnivorous theropod.