Eucalyptocrinites sp.   scale in cms CLASS - Crinoidea ORDER - Monobathrida FAMILY - Eucalyptocrinitidae GENUS/SPECIES - Eucalyptocrinites sp. ROCK UNIT - Waldron Shale AGE - Silurian (425 million years old) LOCALITY - Nashville, Tennessee, USA The strongly calcified crown (main body portion) of this crinoid has wedge-shaped embayments in which the delicate arms could retract during times of turbulence or attack by predators. PRI 42163