PLATE XVIL 
Pleurotomaria arata. 
Page 64* 
Fig. 1. The upper side of the spire of a very characteristic specimen^ somewhat compressed vertically, but 
not greatly distorted. 
Fig. 2. The same, showing the depth of the volutions and form of the aperture. 
Fig. 3. Basal view, showing the umbilicus. 
Fig. 4. A cast, with unusually elevated spire and rotund volutions. 
Fig. 5. The summit of the same individual. 
Fig. 6. A vertically compressed specimen forming a strong contrast with fig. 4. 
Fig. 7. The upper surface of an obliquely compressed specimen which preserves the characteristic markings, 
and shows the spiral band with retrally curving striae, as in fig. 1. 
Fig. 8. An obliquely compressed specimen with finer surface-markings. 
Pleurotomaria arata var. clausa. 
Page 65. 
Figs. 9,10. Two views of a small gibbous specimen which bears a close resemblance to the more rotund 
forms of P. arata. 
Pleurotomaria plena. 
Page 66. 
Figs. 11-13. Three views of a large, well-formed specimen, showing the form, surface-markings and spiral 
band. The outer volution is represented as slightly too rotund. 
