Anastrophia Brachiopod

Waldron Shale brachiopod found in Clark County, Indiana.  The creature existed in the Middle Silurian Period.  My best guess as to its identification is the Anastrophia.  If one looks at the third picture, showing it from a hinge view it has been compacted.  Refer to the Indiana State Museum collection record for this genus.

Melonites multipora Sea Urchin

The Melonites multipora sea urchin fossil found in St. Louis, Missouri.  The creature existed in the Mississippian Period.  It was on display at the Smithsonian Museum of Natural History (August 2010).  The description said it was once the size of grapefruit before getting flattened during fossilization.

Promicroceras planicosta

Ammonite fossils of the Promicroceras planicosta on display at the Smithsonian Museum of Natural History in Washington D.C., USA.  Rock plate is from England and the creatures date to the Early Jurassic Period (188-184 million years ago).

I have one of these fossils from Lyme Regis, England.  See it at this previous posting.

Learn more at this entry on Wikipedia.