1. Left valve, dorsal aspect; 1a, umbonal region of the same 2. Right valve; 2a, dorsal aspect; 2b, frontal aspect. Same 3. Interior of a right valve. Same locality (42h). PAGE 110 4. Right valve; 4a, frontal view; 4b, dorsal aspect of the umbonal 5. Left valve. From the South African Museum collection; |