LOWER CttALK —DEN ONSHTUE. 
143 
gritty limestone with large Rhynchonella, but few other shells, lie 
on the grass and testify to its existence above ; with them are squared 
blocks of the shelly limestone (A2), which seem to have been used 
for building stone. 
At the top of the east end of Higher Dunscombe cliff the base of 
the Middle Chalk can just be reached. Below it are 2 feet of Bed B, 
containing large Rhynchonella dimidiata, and rather more than 
2 feet of hard, whitish shelly stone (A2). In the old quarry near by 
the outcrop of the latter can be seen, and below are 18 inches of 
coarse pebbly grit with some fossils (Al), resting on massive calcareous 
sandstone. 
The course of these beds along the cliff-top could not be reached 
without risk of life, unless, perhaps, by the aid of men and a rope ; 
but, fortunately, we are not left without evidence that all three 
Cenomanian beds continue and actually thicken locally to the west¬ 
ward. This evidence is obtained from the large fallen blocks which 
lie on the shore below the western part of the cliff, which is 
known as Maynard’s cliff. One of these gave a vertical succession 
of about 9 feet, the whole belonging to the zone of Am. Mantelli , 
and having the following composition : — 
B. Hard gritty limestone with white chalky matrix, large quartz 
and small glauconite grains ; many large green-coated lumps 
throughout the mass, these are brownish inside, but consist 
of the same material as the rest; the base of this is welded on 
to the next. Thickness, 2 feet. 
A2. Very hard sandy limestone of finer grain, full of shells and hard 
whitish calcareous lumps, some of which are Bryozoa ( Mem- 
branipora , etc.), passing into next. Thickness, about 4 feet. 
Al. Bough calcareous grit, shelly in upper part, becoming very coarse 
in lower part, with some quartz grains as large as peas Ceriocava 
ramulosa very common in lower part. 
This block included from 3 to 3 J feet of the lowest bed, but another 
one showed about 4 feet, with a flat lower surface, which was pro¬ 
bably the basal plane. Corals were common in the lower 3 feet of 
this ; but in neither block was there any sharp division between 
Al and A2, the one passing into the other more completely than in 
any other exposure seen to the west of Hooken cliffs. The change 
from coarse to finer-grained rock is, however, rather rapid. It is 
curious that at this, the most westerly outcrop of the Cenomanian, 
its thickness (10 feet) should be greater than it is anywhere else 
along the coast, except at Hooken and Beer Head. 
Bed B is clearly Mr. Meyer’s 12, and yields Holaster subglobosus, 
Rhynchonella dimidiata, Rh. grasiana, and Kingena lima. 
Bed A2 (Mr. Meyer’s 11) contains many fossils, of which the 
commoner are Trigonia (several species), Discoidea cylindrica, 
Gottaldia Benettice, Pseudodiadema ornatum, Neithea cequicostata 
and Terebratula ovata. 
The lowest bed is Mr. Meyer’s No. 10, and contains the charac¬ 
teristic coral-like Ceriopora. 
