 <unk> and other similar animals were referred to as <unk> , named like <unk> for teeth that were highly folded in cross section . Owen 's " <unk> <unk> " was later found at Guy 's <unk> , England by paleontologist William Buckland . Other specimens were found in the red sandstone of Warwickshire . As more fossils were uncovered in England , Owen depicted these <unk> as the " highest " form of <unk> and compared them to <unk> , which he considered the highest form of reptiles . He also noted the large <unk> of the <unk> ( a unit of rocks that dates to the Late <unk> ) were younger than more advanced reptiles in the <unk> and <unk> , which are Late <unk> in age . Owen used these fossils to counter the notion that reptiles evolved from a <unk> progression from early amphibians ( what he called " <unk> fishes " ) . 
