212 DAVIS : SECTIONS IN THE LIASSIC AND OOLITIC ROCKS OF YORKSHIRE. 
Fb. Ins'. 
4. Middle Calcareous Grit. Soft thin sandy beds or gritty 
limestones, with Modiola, Pecten, and Terebratula 20 0 
5. Lower Oolitic Limestone. Flaggy limestone at top, 
changing to small-grained oolites towards the 
centre, and thick-bedded fossiliferous limestones 
forming the base, with GerciUia, Ostrea, and 
Gryphwa, This series is quarried for lime ... 20 0 
6. Lower Coral Rag. A hard brown ferruginous coral 
limestone, very fossiliferous, mainly composed of 
corals ... ... ... ... .. 8 0 
7. Passage or Basement Beds. A series of impure 
siliceous flaggy limestones, very ferruginous, and 
in some cases composed of comminuted shells, 
with Gervillia, Exogyra, &c. .. ... 25 0 
Lower Calcareous Grit 
The Upper Oolitic Limestone, with the superincumbent Coral 
Rag, is much more fossiliferous than the Lower Limestones. At 
Ayton, a few miles south-east of . Hackness .and four miles from 
Scarborough, fossils are very abundant in this rock. From these 
districts the following fossils have been obtained : — 
Thecosmilia annularis, Flemg. Astarte ovalis, Sow. 
Cidaris florigemma, Phil. A. Aytonensis, Lyc. 
C. Smithn, Wright. Chemnitzia Heddingtonensis, Sow. 
Echinobrissus scutatus, Lam. Pecten vimineus, Sow. 
Hemicidaris intermedia, Flem. P. fibrosus, Sow. 
Holectypus depressus, Lam. P. lens, Sow. 
Pseudodiadema versipora, Phil. Hinnites velatus, Goldf. 
Natica arguta, Phil. Lima fragilis, Rom. 
Cerithinin inornatum, Buvig. L. rudis, Sow. 
C. limseforme, Rom. L. rigida, Sow. 
C. Humbertinum, Buv. Perna mytiloides, Lam. 
Nerimea fusiformis, D'Orb. Area quadrisulcata, Sow. 
N. fasciata, Voltz. A. pectinata, Phil. 
Littorina muricata, Sow. Cucultaa elongata, Phil. 
Turbo fumiculatus, Phil. Myoconcha texta, Buv, 
