A 3-D computer illustration of the extinct marine echinoderms known as Caryocrinites, a type of cystoid (genus of the class cystoidea), that existed from the Ordovician period to the Silurian (which occurred from 505 to 438 million years ago). Caryocrinites is characterized by a 2.5 cm spherical body made up of plates with featherlike arms (pinnules) attached to a long stem fixed to the sea floor. The mouth and anus were openings in the polygonal plates. Though purely an artistic interpretation, the structure of the animal is inferred through scientific notation and fossil impressions of what the species may have looked like within the environment in which it existed.