Stock Photo: Fossil of extinct corals: Astraea cristata, Maeandrina tenella, A. caryophylloides and Chaetetes polyporus. Handcoloured lithograph by an unknown artist from Dr. F.A. Schmidt's "Petrefactenbuch," published in Stuttgart, Germany, 1855 by Verlag von Krais & Hoffmann. Dr. Schmidt's "Book of Petrification" introduced fossils and palaeontology to both the specialist and general reader.