Mr. William Phillips on the 
28 
small indented circle upon each : when not solid, they always con- 
tained a nucleus having the appearance of a sponge of the same shape 
as the flint : these rarely exceed an inch in diameter. Others are 
cylindrical, and inclose another flint of the same form ; others (and 
they are numerous) are conical, having a flat base, around which is 
always indented an oval, within which there is sometimes the in- 
dented mark of a sponge : some of these are solid, others are lined 
with tuberculated chalcedony of a bluish aspect ; these are about two 
inches high : a thin lining of blue chalcedony, which is extremely 
greedy of moisture, is by no means uncommon within some of the 
flints of this bed. There are others very common to it, whose ex- 
ternal marks, consisting either of deep indentations or small rugged 
projections, bespeak the probability of their formation being in some 
way or other connected with organic matter. But there are other 
flints which it is not easy to describe. They inclose a cylindrical 
flint, resembling the stem or a branch of a vegetable, which, passing 
along the mass, is visible at each end, where sometimes it divides into 
numerous little branches : another of the same description crosses it, 
giving to the external flint a peculiar shape, and inducing the belief 
that it must have been deposited around some organic substance, of 
which the form is preserved by the internal ramifications. The 
whole of these flints are numerous in this bed of organic remains ; 
but I did not discover any resembling them in form and character 
in any other part of the chalk. 
The numerous shells of the echinus, or rather the calcareous spar 
which has replaced them, are almost always whole ; rarely was one 
visible that had suffered depression ; but the chalk with which they 
are filled, instead of being finer than that in which they lie, as is 
frequently the case in the echini of the upper part of the chalk with 
numerous flints, is on the contrary much coarser and of a somewhat 
sandy aspect. 
