Cyathocrinus

Cyathocrinus, one of the best known genera of the Sea-lilies of the Palaeozoic era. It is the type of the family Cyathocrinidae, and it ranged from the Silurian to the Carboniferous periods. It belongs to the group "Inadunata," as the arms are quite free above the dorsal cup. The calyx was small, and the plates loosely attached; hence, they readily fell to pieces on the death of the animal. The stem was large, cylindrical, and composed of many thin ossicles, or joints. The genus was especially common in the Upper Silurian of the Wenlock district, from which locality the best English specimens are derived.