224 
DESCRIPTION OP THE FOSSILS. 
M. pileus. Ph. PI. XIV. fig. 7. Bolland. 
Conical, smooth. 
M. imbricata. Ph. PI. XIV. fig. 8. Bolland. 
Conical, concentrically ribbed. 
M. elliptica. Ph. PI. XIV. fig. 9. Bolland. 
Convex, vertex terminal. 
M. oblonga. Ph. PI. XIV. fig. 10. Bolland. 
Oblong, convexo-conical ; limb rounded, expanded in front. 
M. sulcata. Ph. PI. XIV. fig. 11. Bolland. 
Convex, concentrically sulcate. 
Pileopsis ? trilobus. Ph. PI. XIV. fig. 12, 13. Bolland. 
Subconical, arched, narrowed toward the incurved free apex ; aperture trilobate. 
P. tubifer. Sow. PL XIV. fig. 14. Bolland. 
Narrow, arched ; three rows of spines ; (the middle one obscure.) 
P. striatus. Ph. PI. XIV. fig. 15. Bolland; Kildare County; 
Northumberland. 
Oval, arched toward the incurved free apex ; sharp radiating striae. 
P. neritoides. Ph. PI. XIV. fig. 16, 17, 18. Bolland. 
Obliquely spiral ; spire flattened ; lines of growth strong, irregular ; aperture oval; 
concentric striae on the base. 
P. vetustus. ? Sow. PI. XIV. fig. 19. Bolland. 
Subconical, irregular, apex spiral ; surface with spiral folds ; aperture round ? 
P. angustus. Ph. PI. XIV. fig. 20. Bolland. 
Spiral, apparently smooth, narrow ; aperture expanded. 
Natica ampliata. Ph. PL XIV. fig. 21, 24a. Bolland; Northum- 
berland, 
Hemispherical, spire of two inconspicuous volutions ; lip expanded, columella 
plane ; striae equal, filiform. 
N. lirata. Ph. Pl. XIV. fig. 22. Bolland. 
a. oval, spire mammillary, of two or three volutions, crossed by equidistant lamina? ; 
(3. spiral interlaminar striae. The shell is smooth within. 
N. elliptica. Ph. Pl. XIV. fig. 23. Bolland ; Northumberland. 
Depressed, elliptical, spire short ; striae oblique, fine ; columella arched, plane. 
N. planispira. Ph. Pl. XIV. fig. 24. Bolland. 
Columella callous above, top of the volutions planate, plicistriate. 
N. variata. Ph. Pl. XIV. fig. 26, 27. Bolland. 
Oval, depressed, apex acute ; striae partly oblique and partly spiral. 
