Pentremites welleri   CLASS - Blastoidea ORDER - Spiraculata FAMILY - Pentremitidae GENUS/SPECIES - Pentremites welleri ROCK UNIT - Paint Creek Formation AGE - latest Mississippian (325 million years old) LOCALITY - Floraville, Illinois, USA This specimen of the blastoid Pentremites has many of its simple, unbranching arms intact. These arms collect and carry food to the mouth along large "food grooves." Blastoid arms are loosely held together by soft body tissue which decays quickly after death. The individual plates of blastoid thecae (main body portion) are fused together, making it resistant to destruction. PRI 42151