File:The Quarterly journal of the Geological Society of London (12735866815).jpg

268
J. F. BLAKE AND W. H. H1TDLEST0N ON
And about 22 ft. below this occur the great doggers previously
noticed on the coast.
Nearly the whole of this section shows oolitic conditions, though
the beds are very various in character, illustrating what has been
very forcibly impressed upon us, that these Corallian beds cannot be
trusted to be constant any further than we can see them. The
upper portion, as on the coast, is the most fossiliferous. Passing
on in the same direction to Wyke, we find the whole series here
indicated massed into one suboolitic, false-bedded, rubbly lime-
stone, indicating, perhaps, a source of the calcareous material
situated to the west ; but of this section we need not give details.
The beds corresponding to these Trigonia-heds at Osmington are
a perfect mine of wealth to collectors ; and the matrix being peculiar,
the locality of hand specimens is easily identified. The upper part
of the limestones here becomes a large-grained purple oolite, the
marly partings becoming a soft oolitic rock from which the fossils
are extracted in good preservation. Blocks may be obtained covered
with double valves of Trigonia clavellata with the ligament unin-
jured ; and hence is said to have come the beautiful coral Comoseris
irradians, figured by Edwards and Haime, as well as other corals,
which, however, are by no means common.
From this locality the same beds may be traced at various points
along their outcrop, always characterized by their extremely fossili-
ferous nature, being, indeed, largely composed of shells, and showing-
very little oolitic structure. In a quarry in this stone at Broadwey,
Mr. Damon has recorded the occurrence of Ceromya eoccentrica
(Ag.), a fossil of importance in some localities.
View of Linton Hill from the North.
a. Oolite Quarry
b. T?'igonia-heds. c. S'andsfbot Grits.
d. Iron Sands.
The development of these and the overlying beds near Abbotsbury
is admirably seen in the picturesque elevation called Linton Hill
(fig. 1). Its gently sloping sides are scored obliquely by two cliff-like
escarpments passing over it from S.S.W. to N.N.E. These are due
to the succession of hard beds which have a rather less slope to the
east than the surface of the ground ; they crop out in succession in a
long longitudinal valley to the south, where the largo tabular doggers