Ill 
This is from a clay stratum at Barton, it was sent me by 
my friend the Rev. F. Iremonger, it is a more delicate species 
than the preceding, and the substance seems but little 
altered ; it resembles ivory. 
TURRITELLA incrassata. 
TAB. LI. — Fig. 6. 
Spec. Char. Whorls flatfish, with the lower part 
angular and three smooth longitudinal threads ; 
outer lip thickened in the middle. 
Length two inches, whorls about fourteen; two of the 
spiral threads are much more prominent than the third, 
particularly the central one, opposite to which, in full 
grown shells, there is an internal projection that gives 
thickness to the outer lip; besides this it is altogether a 
strong shell: the inner lip spreads over an umbilicus. 
This is also from Holywell, it has a plain appearance, 
perhaps from being worn. 
TURRITELLA edita. 
TAB. LI. — Fig. 7. 
Spec. Char. Whorls rounded, slightly depressed 
in the middle, lower parts rather prominent 
with many obscure longitudinal striae. 
Turbo editus. Brander , Tab. 3 . Fig. 48. 
A long slender formed shell with about twenty whorls; 
length three inches . 
