Paracyclas elliptica Devonian Clam

Here is a Devonian period clam found in the Silver Creek formation. This formation can be found in Clark County, Indiana. The clam is known as Paracyclas elliptica (Hall).

The Smithsonian has a collection for a geologist named Henry Nettelroth (1835-1887) and they have some reports I found on-line. I think they are from the mid to late 1800s when a lot of the fossils in the Louisville area were named. Nettelroth refers to the Silver Creek formation as "hydraulic limestone". Also he refers to Clark County as Clarke County. I have also seen Speed, Indiana USA referred to as Speeds, Indiana in older texts.


UPDATE: This entry has been modified with a picture of another clam fossil. As of August 2010, this fossil was on display at the Smithsonian Museum of Natural History. It list it was found in Kentucky.

Kentucky Agate

Here is a polished Kentucky agate. It a great mineral found here in the state and while it does not quite fit fossil theme of this blog maybe it contains some fossilized moss.


UPDATE: A fellow KYANA Geological Society member looked over this entry and pointed out some issues. She pointed out this agate formed inside a brachiopod. Remnants of the shell can be seen around the edge. So this really is somewhat of a fossil. Also it should be classified as a rock instead of a mineral.

The Paracyclas elliptica Clam

Here is a clam called Paracyclas elliptica from the Devonian period. It was found in Clark County, Indiana in the Silver Creek formation.