Kingdom Animalia Linnaeus, 1758 - animals Phylum Echinodermata Bruguière, 1789 - echinoderms Subphylum Echinozoa von Zittel, 1895 see Infraphylum Echinozoa Haeckel, in Von Zittell, 1895 Class Echinoidea (Leske, 1778) - sea urchins and sand dollars Order Clypeasteroida A. Agassiz, 1872 - true sand dollars Genus Echinocyamus van Phelsum, 1774 Genus Mellita Agassiz, 1841