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extract them. An accidental fracture may expose the internal 
structure, or the external surface of part of a shell, which 
may possibly with very great care and patience be cleared. In 
this way I obtained a very fine specimen of a Trigonia, belong- 
ing to the wndulate. T consider it to be a variety of T. wndulata, 
as it differs in form from that shell, as described by Lycert in 
the monograph of the Trigonie, published by the Palzonto- 
graphical Society. It is much higher in comparison with its 
breadth, and has a narrower area and more curved umbones 
than is shown in the published figures, and is much larger in 
size. (Plate IV., fig. 6.) 
The shelly Weatherstones of the Great Oolite do not 
appear on the surface in the area under description. They 
occur in the greater part of the Cotteswolds, and come next to 
the White Limestone, which they underlie. They extend beyond 
the margin of the Limestone area in almost every direction. 
At Minchinhampton Common they are about fifteen feet thick. 
At Tiltup’s End the Section is not sufficiently deep to expose 
them, but they may be seen in the road-side quarry near 
Kingscote, as before mentioned, where they appear to have 
become less shelly, except the upper two feet, which contain a 
fair assemblage of shells. Here they agree with a similar bed 
in the village of Nympsfield, half a mile south of Frocester hill, 
where there is a small section of Great Oolite, containing a 
shelly bed, three feet thick. A mile west of Kingscote, on the 
Wotton-under-Edge road, the beds are well exposed in a large 
road-side quarry, but they are no longer shelly, as at Minchin- 
hampton ; a few fossils, chiefly small valves of Oysters, occur, 
but the character of the beds is that of a rock composed of 
shelly detritus Oolitic granules and sand. 
At the Ridge, and not far from the top of Wotton hill, is 
the quarry probably alluded to by Dr Lycerr, whose description 
of the rock as quoted above, is perfectly accurate. The shelly 
beds therefore may be described as commencing west of 
Kingscote, and a line drawn from thence to Frocester hill will 
sufficiently indicate their western extremity. Possibly they did ~ 
not quite thin out at this line, but owing to the denudation of 
