Linn. Soc, N.S.W., 1883, Plate 12. 



Fig. 



Fig. 2. 



Fig. 3. 



Fig. 5. 



Fig. 4. 



Fig. 6. 



Fig. 1. Trigonia mesembria. 



Fig. 2. Do. do. upper surface. 



Fig. 3. Do. do. anterior end. 



Fig. 4. Avicula barhlyi. 



Fig. 5. Do. do. right valve. 



Fig. 6. Fragment showing ribs. 



