Caryocrinites ornatus   scale in cms CLASS - Cystoidea ORDER - Rhombifera FAMILY - Caryocrinitidae GENUS/SPECIES - Caryocrinites ornatus ROCK UNIT - Rochester Shale AGE - Middle Silurian (425 million years old) LOCALITY - Niagara County, New York, USA Individual plates and whole thecae (main body portion) of the cystoids like Caryocrinites are common in the Silurian and Devonian strata representing shallow sea environments. Rhombiferan cystoids, like Caryocrinites, have a distinctive rhombic pattern of pores or slits on the surface of adjoining thecal plates. These pores/slits are used for respiration. PRI 43589