Texas Pennsylvanian Fossils

The Phylum Mollusca is a large and varied invertebrate group within the Animal Kingdom. They are characterized by a soft body with a strong muscular foot and usually (but not always) covered by a shell. The Polyplacophorans (Chitons) are a small and relatively obscure Class of mollusks characterized by eight loosely articulated plates that are embedded within a muscular girdle atop the foot. They first appeared in the Late Cambrian and their general form has remained relatively stable up to the present. 

In the Finis, only a few isolated plates from three genera have been identified. They are small and very rare. 

----------------------------------------------------------------------------------------------------------------------------------------