In a broad search for precedents to substantiate modern-day Nautilid pearls, extremely rare paleo-pathological work has been of great interest. Attached from an obscure monograph (thanks to Princeton University for an excellent scan) is a Pleuronautilus pseudoplanilateratus (Kieslinger, 1916), Middle/Late Triassic (200+MYA) from Timor, Indonesia. Alois Kieslinger was in his immediate post-doctorate career when traveling as a member of the 1916 Dutch Timor Expedition, later to become associated with research into stone monument preservation, including the Parthenon in Athens. What is of extreme interest to me is the incredible similarity of shell morphology between the Pleuronautilus and N. Pompilius (note how Kieslinger's figure and a modern Nautilus shell section match coils perfectly, showing the body chamber location of the pearl blister). Even the most optimistic research (unpublished, P. Ward) has modern Nautilus appearing only as early as the late Mesozoic. Kieslinger's Pleuronautilus is a dead ringer for the mysterious Allonautilus Perforatus, known only from drift shells and (along with A. Scrobiculatus) thought to be the most recent evolution of Nautilida. Will be very interested to discover the differences between this Triassic Nautiloid and modern Nautilus shells.