A lens bounded by two circular arcs, in the shape of a <a href="https://en.wikipedia.org/wiki/Vesica_piscis" class="extiw" title="en:Vesica piscis">vesica piscis</a>, together with two collinear rays emanating from the corners of the lens. This network of two arcs and two rays is the limiting shape for all networks of two curves and two collinear rays under the <a href="https://en.wikipedia.org/wiki/Curve-shortening_flow" class="extiw" title="en:Curve-shortening flow">curve-shortening flow</a>.
<a href="//commons.wikimedia.org/wiki/User:David_Eppstein" class="mw-redirect" title="User:David Eppstein">David Eppstein</a>
<span class="int-own-work" lang="en">Own work</span>