DESCRIPTION OF PLATE X. 
Fig. 
1. Lateral aspect of the Faiijasina. Magnified 30 diameters. 
2. Superficial section of the fiat base of the shell. Mag. 60 diameters. 
3. Horizontal section parallel to the last, across the points & &, in fig. 1. 
Mag. 60 diameters. 
4. Horizontal section across the points c c in fig. 1. Mag. 60 diameters. 
5. Vertical section across the points dd'm fig. 1. Mag. 60 diameters. 
6. Superficial section from the oblique side of the shell. Mag. 80 dia- 
meters. 
VOL. I. 
