Reticulariina spinosa Brachiopod

 Reticulariina spinosa brachiopod found in the Hardinsburg Formation of Hart County, Kentucky. Fossil dates to the upper Mississippian Period. Thanks to Mark for the fossil.

Icriodus Conodont Fossil

This fossil appears to be an Icriodus angustus? conodont found in either the upper Devonian New Albany Shale or Middle Devonian Beechwood Limestone of Clark County, Indiana.

Conodonts have been found in the southern Indiana for a while. In 1938, a new species found at the Falls of the Ohio was named Icriodus latericrescens by E.G. Branson and M.G. Mehl

While doing some conodont research, I came across an article about a researcher at the University of Houston named Glen Merrill.  Dr. Merrill is a professor of Natural Sciences and has been publishing papers for over 50 years. His laboratory has collection approximately 750,000 conodonts. The article states that "Each conodont animal had seven kinds of elements that were surrounded by soft tissues and grew layer on layer."

Another item gleaned from the article is that the fossils change color when exposed to heat. From amber they go to brown, grey or black and eventually opaque and then vaporize. Oil companies became interested in this property as they found gas/oil in layers that had been heated and these fossils could be studied as thermal markers.

Read this informative article entitled UHD's Award Winning Faculty Series: Meet Glen Merrill from June 23, 2011 at the University of Houston Downtown web site: http://uhdnews.uhd.edu/news/stories.aspx?articleid=245&zoneid=1

Conostichus Trace Fossil

Trace fossil that might be some sort of sea anemone burrow. These traces fossils can be referred to as Conostichus. Fossils were found in the Bangor Limestone of Colbert County, Alabama. The traces were made in the Mississippian (Carboniferous) Period about 325 million years ago.

Thanks to Larry for the fossils.

Learn more about these type of fossils at the Indiana Geological Survey web site on a page written by Henry H. Gray:  Conostichus, an Enigmatic Fossil.