Here is a trilobite found by a KYANA Geological Society ( www.kyanageo.org ) member on a field trip some years ago. It is a Trimerus delphi...

The side view of a Trimerus delphinocephalus found in Clark County, Indiana in the Waldron Shale layer. The creature lived in the Silurian ...

Here is the back thorax of a Trimerus type trilobite from the Silurian period. It is described in more detail on page 98 of the Fossils of...