The Echinoid Directory

Tetraromania ovulum (Desor, 1842); Berriasian, Lower Cretaceous, former Soviet Union. Oral plating and ap[ical disc plating (ambulacral plates in black). From Solovjev, A. 1971. Late Jurassic and Early Cretaceous disasterids of the USSR. Transactions of the Palaeontological Institute, Academy of Sciences of the USSR 131, 1-120, pls 1-16 [in Russian] (Fig. 30).