200 DAVIS : SECTIONS IN THE LIASSIC AND OOLITIC ROCKS OF YORKSHIRE. 
Hard grey ironstone . . . 
Shale, with fossils 
Hard ironstone, with fossils 
Shale, full of fossils ... 
Ft. Ins. 
0 10 
1 6 
0 6 
4 0 
Total ... ... ... . . ... 6 10 
From the shales are obtained Avicula Braamburiensis, Ostrea 
flabelloides, and other fossils. The beds are devoid of limestone, and 
as they sink from the cliffs to the beach would be extremely difficult 
to follow but for the characteristic sandstone of the Middle Estuarine 
Series. This is finely laminated and beautifully interstratified with 
thin black carbonaceous seams, while immediately under, lies the 
Scarborough Series. It extends in long well-marked reef across the 
bay, midway between the cliffs and the outer reef of the Millepore 
bed. 
In Cayton Bay the bed is again seen at a point east of the great 
fault at Red Cliff. (Fig. 7.) In the Bay it forms the outermost 
portion of the island of Calf Allen Rocks. 
The Upper Estuarine Series succeed the Scarborough beds, and 
consists of an irregular mass of sandstones and shales, with a few 
thin ironstone bands and much carbonaceous matter. The beds rise 
from the shore into the cliffs, and form a bold face at Gristhorpe Bay ; 
at the north-western end of the Bay there is the following section 
'exposed :• — 
Ft. Ins. 
Shale, with two bands of thin sandstone ... ... 500 
Strata, probably shale, but much obscured by land- 
slips ... ... ... ... ... 38 0 
Beds, mostly sandstone, forms the first reef in the 
Bay ... ... ... ... ... 15 0 
Granular ironstone band ... ... . . 10 
Sandstone, with coaly streaks and sulphur ... 20 0 
Total ... ... 124 0 
The sandstones predominate mostly in the lower part, and are 
very false-bedded and lenticular. The granular Ironstone Band, 
one foot in thickness, forms a well-marked band of nodules exposed 
