Here is a Mississippian horn coral found in Crawford County, Indiana. It is small maybe 3 cm in height.

Here is a tabulated coral called Thamnoptychia alternans from the Devonian Period. It was found in Clark County, Indiana.

Here is a piece of the crinoid stem called Eucladocrinus. It existed in the Mississippian Period. This one was found in Floyd County, Ind...