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DESCRIPTION OF THE FOSSILS. 
P. excavata. Ph. PI. XV. fig. 20. Bolland. 
Conical, whorls carinated at the angle, nearly plane above and below, umbilicus 
closed. 
P. acuta. Ph. PI. XV. fig. 21. Bolland. 
Whorls tumid, sharply carinated ; oblique stride above the keel, spiral lines below, 
(a reversed shell.) 
P. conica. Ph. PL XV. fig. 22. Bolland ; Derbyshire. 
Conical, acute, umbilicate ; band bicarinate, striae acutely elevated and oblique 
above. Some varieties have three keels, a sulcus separating the two upper ones. On 
some specimens are spiral striae. 
P. concentrica. Ph. PI. XV. fig. 23. Bolland. 
Turrited, whorls quadrate, convex below, plane above, spirally sulcated; basal 
furrows largest, umbilicus closed. 
P. vittata. Ph. PI. XV. fig. 24. Bolland ; Otterburn. 
Turrito-conical, whorls convex, band very broad, and flat ; striae slightly oblique. 
P. tornatilis. Ph. PI. XV. fig. 25. Bolland. 
Ovate, whorls convex ; band very broad, a furrow on each side ; spiral striae above 
and below, two basal furrows. 
P. lielieoides. Sow. PI. XV. fig. 26. Bolland. 
Depressed, umbilicate ; whorls rounded ; lines of growth faint, rctroflexed in the 
middle ; aperture lunate ; edge of umbilicus spirally striated. 
P. ovoidea. Ph. PI. XV. fig. 27- Bolland ; Derbyshire ; Isle of Man ; 
Otterburn in Northumberland. 
Ovate, whorls subangulate below, lines of growth flexuous. 
P. glabrata. Ph. PL XV. fig. 28. Bolland. 
Lenticular, rounded, smooth. 
P. biserrata. Ph. PL XV. fig. 29- Derbyshire. 
Conical, acute ; sutural edge and lower angle of the whorls carinato- dentate ; 
between them a crenulated line ; base with three furrows ; oblique stria;. 
P. serrilimba. Ph. Pl. XV. fig. 30. Derbyshire. 
The angle of the spire more acute than in the last. 
Melania constricta. Sow. Pl. XVI. fig. 1- Bolland; Kirby Lons- 
dale ; Tideswell ; Kildare. 
Turrited, smooth ; whorls tumid below, contracted above, with a crenated sutural 
margin. 
M. sulculosa. Ph. Pl. XVI. fig. 1, a. Bolland ; Kildare. 
Elongated, volutions convex, with longitudinal arched sulci deepening toward the 
lower part of the whorls. 
