A phragmocone showing the ventral (?)* aspect of the chambered apex, with two parallel longitudinal bands extending upwards (b)<br><p><br></p>
<ul><li>(actually dorsal, Mantell was incorrect)</li></ul>
<a href="https://en.wikipedia.org/wiki/Gideon_Mantell" class="extiw" title="w:Gideon Mantell">Gideon Mantell</a>
<i><a rel="nofollow" class="external text" href="https://books.google.com/books?id=tGwOAAAAIAAJ&amp;printsec=frontcover#v=onepage&amp;q&amp;f=false">Philosophical Transactions of the Royal Society of London</a></i>. For the Year MDCCCXLVIII Part I