Cyclonema Snail Fossil

These fossil molds of the ancient gastropod Cyclonema were found in Franklin County, Kentucky.  This snail existed in the Ordovician Period.  The fossil was found in the Lexington Limestone.  It is of the class Gastropoda, suborder Euomphalina, and superfamily Platyceratacea.  The genus Cyclonema was named by James Hall in 1852.