Historical drawings of aptychi (i.e. calcified lower jaws of ammonites that possibly served as cap for the opening of the shell when the soft body was retreated) from the Upper Jurassic of NW Switzerland, figured and described as bivalve shells (“<i>Tellinoides</i>”) in this work. According to Trauth (1931)<sup id="cite_ref-trauth31_1-0" class="reference"><a href="#cite_note-trauth31-1">[1]</a></sup> these drawings show specimens of <i>Laevaptychus longus</i> (<style data-mw-deduplicate="TemplateStyles:r369756387">.mw-parser-output .smallcaps{font-variant:small-caps}</style><span class="smallcaps">Meyer</span> 1829) in external (top) and internal (bottom) views.
Johann Jakob Scheuchzer (1672-1733); modified by <a href="//commons.wikimedia.org/wiki/User:Gretarsson" title="User:Gretarsson">Gretarsson</a>
1702
<a rel="nofollow" class="external text" href="http://www.e-rara.ch/zuz/content/pageview/3760754">Figs. 27 and 28 of plate 2</a> in <i>Specimen Litographiæ Helveticæ Curiosæ.</i> Printed by David Gessner, Zurich 1702, <a href="//doi.org/10.3931/e-rara-12116" class="extiw" title="doi:10.3931/e-rara-12116">doi:10.3931/e-rara-12116</a>