A Devonian Period fossil called Hippocardia subtrigonale .  It is from Kentucky and is on display at the Smithsonian Museum of Natural Hi...

A Scytalocrinus robustus (Hall, 1861) crinoid fossil from Indiana USA.  This crinoid existed in the Mississippian Period. It is on displa...

  Lyelliceras ulrich 3DMuseum.org / CC BY-NC-SA 3.0 Last week I posted a link to a 3D trilobite image, now I am posting links to a...