Cryptolithus Head Plates

Here are several Cryptolithus sp.trilobite remains found in Carroll County, Kentucky. One still has part of its side spine intact. I have wondered what purpose this spine serves being so close to the body and swept back along the side. Is it possible the trilobite propelled itself backwards with its tail like crayfish do today? As if sped backwards this two spines would protect it if it hit something like a rock or hostile creature?

I also wonder about all the holes along the creatures front rim. Are these some sort of sensory mechanism? I have read this creature is blind so it either navigated with antenna or maybe used this hole system as some sort of detection grid. Of course if it lived in a dark environment, eyes are not really that useful.

This creature lived in the Ordovician period and is in the company of remains from bryozoans and crinoid stems.

Devonian Horn Coral - Tabulophyllum zaphrentiforme

Here is a small horn coral (1.5 cm diameter and 4.5 cm length) that is called Tabulophyllum zaphreniforme (Davis). It is found in the Beechwood Member, North Vernon Limestone, Givetian Stage, and was found in Louisville, Kentucky (central Jefferson County), USA.

This horn coral was known by several other names: Amplexus yandelli Rominger 1876 and Blothrophyllum zaphrentiforme Davis 1887.  E.C. Stumm describes it in Silurian and Devonian Corals of the Falls of the Ohio on page 50, "Coralla simple; subcylindrical to narrowly ceratoid with typical rejuvenation seen where epitheca has been removed.  Calyx with steeply sloping walls. Septa 60-74; major extending almost to axis and probably amplexoid; minor short peripheral ridges."

See Plate 102 of the Blothrophyllum zaphrentiforme figures 8-15 in Kentucky Fossil Corals A Monograph of the Fossil Corals of the Silurian and Devonian Rocks of Kentucky by William J. Davis.

It lived in the Middle Devonian Period (397-385 million years ago) in a shallow tropical sea that covered the area of Jefferson County.  Also see this image at the Indiana Memories Database.

Silurian Colonial Coral

Here is an image of Silurian colonial coral. It was found in central Jefferson County, Kentucky.