Gyroceras elrodi Cephalopod

The illustration shown was drawn by J.C. McConnell and can be found on Plate 37 of the Indiana Department of Geology and Natural History (Eleventh Annual Report) John Collett, State Geologist, 1881. The fossil is identified as a Gyroceras elrodi found in the Silurian Waldron Shale of Indiana.

The next image is of Plate 38 Figure 4 showing a close up of the shell imprint. Described as "Portion of surface showing revolving and transverse lines."

Placenticeras meeki Ammonite

This ammonite fossil is quite ornate with fractal like patterns representing sutures. The ammonite is known as the Placenticeras meeki found in the Pierre Shale Formation of the Badlands of South Dakota, USA. Unfortunately, I did not image it with a ruler but if I recall correctly it was over 10 cm wide.  This animal swam in the Upper Cretaceous (70 million years ago) seas.

The next picture is of a much higher resolution if you want a zoomed in view of the patterns.  The last picture shows the iridescent covering on the other side of the fossil.  Thanks to Mark Palatas for allowing this to be photographed.

Here is a link to flickr showing a very similar one at the South Dakota School of Mines Museum: CLICK HERE

Eucalyptocrinites elrodi Calyx

Super nice fossil specimen of a crinoid calyx called Eucalyptocrinites elrodi. This fossil was found in the Silurian aged Waldron Shale of Indiana.  See more specimens at theWeeks Trilobite site: CLICK HERE

Thanks to Mark Palatas of Louisville for allowing these photographs.