LOWER CHALK—DEVONSH IRE. 
1 36 
Holaster subglobosus and Terebratula arcuata are common in the 
upper bed B, but do not occur in A ; while Pecten asper is common 
in A, and does not, so far as I could ascertain, occur in Bed B. 
Hblaster altus and Hoi. Icevis are also common in A and rare in B. 
The lowest 3 or 4 feet of Bed A is a very coarse grit with large 
quartz grains and some pebbles of vein-quartz and hornstone, but 
fossils are still abundant in it, the branching forms of Ceriocava 
ramulosa being especially conspicuous. Many of these Ceriocava 
are bored bv Lithodomus. Single valves of large Terebratella pectita 
and of Rhynchonella dimidiata are also not uncommon. 
The amount of glauconite in the upper bed seems to vary, the 
more western fallen blocks showing 2 feet of greenish limestone like 
that of Whitecliff, with green stains between the nodular lumps and 
a marked layer of green-coated nodules at the top. 
As these beds are followed with the eye above the pebble-beach, 
which is marked “ Little Beach ” on the 6-inch map, the lower and 
coarser part of A is seen to thin out, leaving this bed only about 
5 feet thick, while B above keeps about 2 feet. 
Where the beds abut against the grass slope of Hooken under¬ 
cliff this lesser thickness seems to be maintained, but they are not 
well exposed or easy of access. 
Fallen masses on the shore below the landslip show that another 
sudden thickening takes place ; the main mass of the landslip at 
the “ Pinnacles ” shows a good, clear, vertical section of these beds 
on its northern side, and another section can be measured by help 
of the talus slope down the face of Hooken cliff, a little to the 
south-east of the Coastguard Station (see Fig. 33). Placing these 
three sections side by side, we have the following remarkable 
evidence of local thickening toward the west, as well as of the 
incoming of a new bed, which is evidently the equivalent of that 
referred to as C near Lyme Regis. 
C. 
B. 
A. 
Shore. 
Pinnacles. 
Rough gritty greenish glauconitic sand in 
chalky matrix, with scattered brown 
phosphates— A ctinocamax plenus - 
0 
4 
Very hard gritty limestone, having a 
thick layer of brownish green-coated 
nodules at top, passing down into hard 
rough nodular whitish gritty limestone, 
with greenish sand in the interstices— 
Holaster subglobosus - - - ' - 
4* 
r 
5 
Very hard calcareous grit, with a nodular 
phosphatised layer at the top, which is 
planed off to a flat surface ; a whitish 
gritty and shelly fossiliferous limestone 
with little glauconite, coarse and rough 
near base, where Ceriocava ramulosa 
occurs; Pecten asper and Holaster Icevis 
common in upper part - 
+ 12 
+ 16 
Totals 
+ 16* 
+ 25 
6 
5 * 
18 
29 * 
