Natural history:fossils.Fossils of extinct ammonite cephalopods: extinct species of Nautilus bidorsatus; and the Ceratites nodosus. The nautilus has changed little over the past 500 million years.Handcoloured lithograph by an unknown artist from Dr. F.A.Schmidt's 鈥楶etrefactenbuch;' published in Stuttgart;Germany; 1855 by Verlag von Krais & Hoffmann. Dr. Schmidt's鈥楤ook of Petrification' introduced fossils and palaeontologyto both the specialist and general reader.