C ] 
F I G. XIX. 
Round, excepting the dexter fide, which is 
truncated : marked with fmall furrows from the 
beaks to the margin. 
Found at Midford on the right hand a little 
beyoud the turnpike. 
FIG. XX. 
Shaped like the laft: ftriated from the beaks to 
the margin: a few^n>parallel to the margin: fome 
are of a light brown, others of a blackifh color. 
Found in the lime-ftone quarries. 
Thefe are the fhells mentioned in the tour 
tliro' the whole ifland of Great Britain,* to be 
found about Twiverton,t in a field, called Marf- 
bury-field, with but little quantity of earth upon 
the rock; which was full of fojfil-jhell, which 
had preferved their natural color of blue and 
white as perfedly as at firft. 
FIG, 
• VoU II. p. 291, 
'I' A Village about a mile and half from Bath on the 
lower Briftol road. 
